A constant concentration dust cloud generator and method

Abstract

The present application relates to the field of coal mine safety, disclose a kind of constant concentration dust cloud generating device and method, the constant concentration dust cloud generating device, including dust storage box, the dust storage box is funnel-shaped, its below is equipped with dust distribution runner, one side of the dust distribution runner is fixed with stepper motor, the lower of the dust distribution runner is equipped with air pipe, the air pipe, dust storage box, dust distribution runner and stepper motor are fixed on frame respectively, one end of the air pipe is fixed with gas mass flow controller, the input of the gas mass flow controller is fixed with fan, the other end of the air pipe is equipped with dust cloud storage package body.In the present application, the device can guarantee dust concentration accuracy, and can maintain the uniformity of dust cloud, become the necessary means of dust sensor and dust measuring instrument calibration, simultaneously produce similar standard gas standard concentration dust cloud, dust sensor calibration, dust measuring instrument research and dust determination etc. work all have important use value.

Description

Technical Field

[0001] This invention relates to the technical field of coal mine safety, specifically to a device and method for generating a constant concentration dust cloud. Background Technology

[0002] In the field of coal mine safety, various instruments for testing harmful gases can be calibrated using gas samples of standard concentrations. However, dust sensors and dust measuring instruments lack standard dust clouds for calibration. The main reasons for this are the difficulty in generating and preserving dust clouds at constant concentrations. Therefore, a constant concentration dust cloud generator is crucial for the calibration of dust sensors, the research of dust measuring instruments, and dust measurement.

[0003] According to Chinese Patent No. CN216978735U, a dust generator with controllable concentration includes an injection pump 1, an atomizing device 3, a high-temperature vaporization device 4, a diffusion chamber 5, a mixing chamber 6, a sampling chamber 7, a gas source pretreatment device 8, a flow control device 9, and a heating module 14; the injection pump 1, the atomizing device 3, the high-temperature vaporization device 4, the diffusion chamber 5, the mixing chamber 6, and the sampling chamber 7 are connected in sequence.

[0004] In the above scheme, dust clouds are generated through a dust-generating solution, an atomizing device, a high-temperature vaporization device, a diffusion chamber, a gas source pretreatment device, and a flow control device. This results in the following disadvantages: When the dust cloud generator is in use, 1) high temperature may cause volatiles contained in organic dust such as coal dust to overflow; 2) due to the different dust densities, it is difficult to distribute the dust uniformly in the solution, which may cause differences in the concentration and uniformity of the dust cloud, thus affecting the calibration of dust sensors, the research of dust measuring instruments, and dust measurement. Summary of the Invention

[0005] The purpose of this invention is to provide a constant concentration dust cloud generation device and method to solve the problems that 1) high temperature may cause the volatile components contained in organic dust such as coal dust to overflow; 2) due to the different dust densities, it is difficult to distribute the dust in the solution uniformly, which may cause differences in the concentration and uniformity of the dust cloud, thus affecting the calibration of dust sensors, the research of dust measuring instruments, and dust measurement.

[0006] To achieve the above-mentioned objectives, the present invention employs the following technical solution: a constant concentration dust cloud generator, comprising a dust storage box, the dust storage box being funnel-shaped, with a dust-collecting wheel positioned below it, a stepper motor fixed to one side of the dust-collecting wheel, and an air duct positioned below the dust-collecting wheel. The air duct, dust storage box, dust-collecting wheel, and stepper motor are respectively fixed to a frame. A gas mass flow controller is fixed to one end of the air duct, and a fan is fixed to the input end of the gas mass flow controller. A dust cloud storage bag body is located at the other end of the air duct, and the outer wall of the dust cloud storage bag body is fixed... The device includes a control panel electrically connected to a stepper motor, a gas mass flow controller, and a fan. A first differential air pressure switch is fixed to one side of the outer wall of the dust cloud storage bag body and is electrically connected to the control panel. A second differential air pressure switch is fixed to the other side of the outer wall of the dust cloud storage bag body and is electrically connected to the control panel. A dust cloud storage bag dust-generating fan is installed inside the dust cloud storage bag body and is electrically connected to the control panel.

[0007] Preferably, the dust collection wheel is composed of an outer wheel wall, an inner wheel wall, thirty auxiliary wires, fifteen dust collection point quantitative dust bins, fifteen dust distribution point quantitative dust bins, a rear circular plate, and a front circular plate. Several of the dust collection point quantitative dust bins and several of the dust distribution point quantitative dust bins have the same volume. Several auxiliary wires are fixedly connected to the inner wheel wall, several dust collection point quantitative dust bins, and several dust distribution point quantitative dust bins, respectively. The outer wheel wall is fixedly connected to the rear circular plate and the front circular plate, respectively. A dust collection port and a dust distribution port are respectively opened at the top and bottom of the outer wheel wall. The dust distribution port at the bottom of the dust collection box corresponds to the dust collection port of the outer wheel wall. The dust collection port covers the dust collection point quantitative dust bins and the adjacent dust distribution point quantitative dust bins before and after it. The bottom of the dust distribution port of the outer wheel wall is connected to an air duct.

[0008] Preferably, a plurality of the dust receiving position quantitative dust bins and a plurality of dust distributing position quantitative dust bins are evenly distributed along the outer edge of the dust distributing wheel, and the central angle of the plurality of the dust receiving position quantitative dust bins and the plurality of dust distributing position quantitative dust bins is 12°.

[0009] Preferably, both the first and second air differential pressure switches consist of an air differential pressure switch housing, an air differential pressure switch positive pressure input port, an air differential pressure switch negative pressure input port, an air differential pressure switch control circuit inlet, an air differential pressure switch pressure reading dial, and a pressure control pointer.

[0010] Preferably, the positive pressure input ports of the first and second air differential pressure switches are fixedly connected to two Pitot tubes inside the dust cloud storage bag body.

[0011] Preferably, the outer wheel wall is cylindrical, the inner wheel wall is cylindrical, the rear wheel plate is annular, and the front wheel plate is annular.

[0012] Preferably, a flange is fixed to one end of the duct near the dust cloud storage bag body, the flange is fixed to the dust cloud storage bag body, and the duct is connected and fixed to the dust cloud storage bag body through the flange.

[0013] Preferably, the thickness of the dust-collecting wheel is 3cm.

[0014] The present invention also provides a method for generating a constant concentration dust cloud, comprising the following steps:

[0015] S1: A dust uniform release device is obtained by controlling the dust output per unit time through a dust-collecting wheel and a stepper motor.

[0016] S2: A production device that obtains a standard concentration dust cloud through a fan, a gas mass flow controller, and a dust uniform release device;

[0017] S3: The pressure of the dust cloud storage bag is determined by the first and second air differential pressure switches, and the start and stop of the fan and stepper motor are controlled. The starting pressure of the first air differential pressure switch is set to h1. When the pressure of the dust cloud storage bag is less than h1, the first air differential pressure switch issues a command, and the fan and stepper motor start working. The starting pressure of the second air differential pressure switch is set to h2. When the pressure of the dust cloud storage bag reaches h2, the second air differential pressure switch issues a command, and the fan and stepper motor stop working.

[0018] S4: A dust cloud storage bag dust-generating fan (its motor and other electrical components are located outside the dust cloud storage bag body) is installed in the dust cloud storage bag body to maintain the uniformity of the dust cloud in the dust cloud storage bag body.

[0019] Compared with existing technologies, a constant concentration dust cloud generator employing the above-mentioned technical solution has the following beneficial effects:

[0020] First, in use, devices that can ensure the accuracy of dust concentration and maintain the uniformity of dust clouds are essential for the calibration of dust sensors and dust measuring instruments. At the same time, they generate standard concentration dust clouds similar to standard gases, which are of great value for the calibration of dust sensors, the research of dust measuring instruments, and dust measurement.

[0021] II. During use, each dust bin fills with dust as it passes by. A dust collection port is located directly below the outer wheel wall, connecting to the air duct. Under the influence of centrifugal force and gravity, all dust from each dust bin is dispersed into the air duct as it passes. The dust cloud dispersed into the duct then enters the dust cloud storage bag body with the airflow. By evenly distributing several quantitative dust collection bins and several quantitative dust collection bins along the outer edge of the dust collection wheel, and setting the corresponding central angles of these bins at 12°, it is advantageous that under the influence of centrifugal force and gravity, all dust from each bin is dispersed into the air duct as it passes, effectively collecting and transferring the dust into the air duct. The design, featuring an air differential pressure switch pressure reading dial and pressure control pointer, facilitates accurate monitoring and reading of air differential pressure values, enabling precise control and adjustment of the system. Furthermore, the positive and negative pressure input ports of the air differential pressure switch allow connection to different parts of the system for monitoring and managing flow.

[0022] Thirdly, during use, connecting to a pitot tube facilitates the measurement of positive pressure within the dust cloud storage bag, thereby enabling control and monitoring of the bag. This connection method also helps ensure the positive pressure and safety of the dust cloud storage bag. By designing the outer and inner wheel walls as cylindrical and the rear and front circular plates as annular, the complexity and cost of manufacturing and processing are reduced. Simultaneously, the cylindrical outer and inner wheel walls provide uniform structural strength, resisting external forces and pressures, and improving stability.

[0023] IV. During use, staff use flanges to connect and secure the duct to the dust cloud storage bag body, ensuring a more secure connection and facilitating maintenance at the duct connection point. Setting the thickness of the dust collector roller to 3cm improves its structural stability, reduces deformation, and thus aids in its operation. Attached Figure Description

[0024] Figure 1 This is a front view of an embodiment.

[0025] Figure 2 This is a structural diagram of the dust collector wheel as an example.

[0026] Figure 3 This is a structural diagram of the first air differential pressure switch in an embodiment.

[0027] Figure 4 The electrical control system diagram of the constant concentration dust cloud generator is shown in the embodiment.

[0028] In the diagram: 1. Outer wheel wall; 2. Inner wheel wall; 3. Auxiliary wire; 4. Quantitative dust collection bin at the dust receiving position; 5. Rear wheel circular plate; 6. Front wheel circular plate; 7. Quantitative dust collection bin at the dust distribution position; 8. Dust distribution port; 9. Air duct; 10. Dust receiving port; 11. Dust storage box; 12. Stepper motor; 13. Dust distribution wheel; 14. Fan; 15. Gas mass flow controller; 16. Dust cloud storage bag body; 17. Dust cloud storage bag dust-generating fan; 18. First air differential pressure switch; 19. Second air differential pressure switch; 20. Control panel; 21. Air differential pressure switch housing; 22. Positive pressure input port of air differential pressure switch; 23. Negative pressure input port of air differential pressure switch; 24. Air differential pressure switch control circuit inlet; 25. Air differential pressure switch pressure reading dial; 26. Pressure control pointer. Detailed Implementation

[0029] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0030] like Figures 1-4 As shown, a constant concentration dust cloud generator includes a dust storage box 11, which is funnel-shaped. A dust-collecting wheel 13 is located below the dust storage box 11. A stepper motor 12 is fixed to one side of the dust-collecting wheel 13. A duct 9 is located below the dust-collecting wheel 13. The duct 9, dust storage box 11, dust-collecting wheel 13, and stepper motor 12 are respectively fixed to a frame. A gas mass flow controller 15 is fixed to one end of the duct 9, and a fan 14 is fixed to the input end of the gas mass flow controller 15. A dust cloud storage bag body 16 is located at the other end of the duct 9. A control panel 20 is fixed to the outer wall of the dust cloud storage bag body 16. The control panel 20 is electrically connected to the stepper motor 12, the gas mass flow controller 15, and the fan 14. A first air differential pressure switch 18 is fixed on one side of the outer wall of the dust cloud storage bag body 16, and the first air differential pressure switch 18 is electrically connected to the control panel 20. A second air differential pressure switch 19 is fixed on the other side of the outer wall of the dust cloud storage bag body 16, and the second air differential pressure switch 19 is electrically connected to the control panel 20. A dust cloud storage bag dust-raising fan 17 is provided inside the dust cloud storage bag body 16, and the dust cloud storage bag dust-raising fan 17 is electrically connected to the control panel 20.

[0031] In use, the dust-distributing wheel 13 rotates around its axis under the drive of the stepper motor 12. The stepper motor 12 can rotate at a certain angle according to the control signal. The combination of the two forms a dust uniform release device, which can realize the uniform distribution of dust. A constant air volume supply system is formed through the fan 14, gas mass flow controller 15, and air duct 9. A constant concentration dust cloud is generated and stored through devices such as the dust collector wheel 13, stepper motor 12, gas mass flow controller 15, dust cloud storage bag body 16, first air pressure differential switch 18, and second air pressure differential switch 19. Operating parameters for the stepper motor 12, fan 14, and gas mass flow controller 15 are obtained by setting the dust cloud flow rate and concentration. When the pressure inside the dust cloud storage bag body 16 (relative to the external atmospheric pressure) measured by the first air pressure differential switch 18 is less than h1, the first air pressure differential switch 18 and the second air pressure differential switch 19 issue commands, and the fan 14 and stepper motor 12 start working, filling the dust cloud storage bag body 16 with a constant concentration of dust cloud. When the pressure inside the dust cloud storage bag body 16 reaches h2 (relative to the external atmospheric pressure), the second air pressure differential switch 19 issues a command, and the fan 14 and stepper motor 12 start working, filling the dust cloud storage bag body 16 with a constant concentration of dust cloud. 4. When the stepper motor 12 stops working, the dust-laden airflow and concentration commands (manually entered) are received from the control panel 20. The speed information of the stepper motor 12 and the airflow information of the fan 14 and the gas mass flow controller 15 are calculated. The stepper motor 12, the fan 14 and the gas mass flow controller 15 are controlled according to the calculated parameters to obtain a dust cloud with constant concentration and constant flow. The dust cloud is transported to the dust cloud storage body 16 through the air duct 9. At the same time, the control panel 20 also receives pressure information from the first air differential pressure switch 18 and the second air differential pressure switch 19 to control the start and stop of the system. This device can ensure the accuracy of dust concentration and maintain the uniformity of dust cloud. It has become an essential means for the calibration of dust sensors and dust measuring instruments. At the same time, it generates a standard concentration dust cloud similar to a standard gas, which has important application value for the calibration of dust sensors, the research of dust measuring instruments and dust measurement.

[0032] like Figures 1-2 and Figure 4As shown, the dust-collecting wheel 13 consists of an outer wheel wall 1, an inner wheel wall 2, thirty auxiliary wires 3, fifteen dust-collecting position quantitative dust bins 4, fifteen dust-collecting position quantitative dust bins 7, a rear circular plate 5, and a front circular plate 6. The dust-collecting position quantitative dust bins 4 and the dust-collecting position quantitative dust bins 7 have the same volume. The auxiliary wires 3 are fixedly connected to the inner wheel wall 2, the dust-collecting position quantitative dust bins 4, and the dust-collecting position quantitative dust bins 7, respectively. The outer wheel wall 1 is fixedly connected to the rear circular plate 5 and the front circular plate 6, respectively. Dust collection port 10 and dust distribution port 8 are respectively opened at the top and bottom. The dust distribution port at the bottom of the dust collection box 11 corresponds to the dust collection port 10 of the outer wheel wall 1. The dust collection port 10 covers the dust collection position quantitative dust bin 4 and the adjacent dust distribution position quantitative dust bin 7. The bottom of the dust distribution port 8 of the outer wheel wall 1 is connected to the air duct 9. Several dust collection position quantitative dust bins 4 and several dust distribution position quantitative dust bins 7 are evenly distributed along the outer edge of the dust distribution wheel 13. The central angle of the several dust collection position quantitative dust bins 4 and several dust distribution position quantitative dust bins 7 is 12°.

[0033] During use, each dust bin fills with dust as it passes through. A dust collection port 8 is located directly below the outer wheel wall 1, and the port 8 connects to the air duct 9. Under the influence of centrifugal force and gravity, all the dust from each dust bin is dispersed into the air duct 9 as it passes through. The dust cloud dispersed into the air duct 9 then enters the dust cloud storage bag body 16 with the airflow. By evenly distributing several quantitative dust collection bins 4 and several quantitative dust distribution bins 7 along the outer edge of the dust distribution wheel 13, and setting the corresponding central angle of these bins to 12°, it is advantageous that under the influence of centrifugal force and gravity, all the dust from each bin is dispersed into the air duct 9 as it passes through, effectively collecting the dust and transferring it into the air duct 9.

[0034] like Figures 1-4 As shown, both the first air differential pressure switch 18 and the second air differential pressure switch 19 consist of an air differential pressure switch housing 21, an air differential pressure switch positive pressure input port 22, an air differential pressure switch negative pressure input port 23, an air differential pressure switch control circuit inlet 24, an air differential pressure switch pressure reading dial 25, and a pressure control pointer 26. The positive pressure input ports 22 of the first air differential pressure switch 18 and the second air differential pressure switch 19 are fixedly connected to two Pitot tubes inside the dust cloud storage bag body 16, respectively. The outer wheel wall 1 is cylindrical, the inner wheel wall 2 is cylindrical, the rear wheel circular plate 5 is annular, and the front wheel circular plate 6 is annular.

[0035] In use, the design of the pressure reading dial 25 with air differential pressure switch and the pressure control pointer 26 facilitates accurate monitoring and reading of the air differential pressure value, which helps in accurate control and adjustment of the system. Simultaneously, the positive pressure input port 22 and negative pressure input port 23 of the air differential pressure switch can be connected to different parts of the system to monitor and manage flow. Connecting to the pitot tube facilitates the measurement of the positive pressure within the dust cloud storage bag body 16, thereby enabling control and monitoring of the dust cloud storage bag body 16. This connection method also helps ensure the positive pressure and safety of the dust cloud storage bag body 16. By making the outer wheel wall 1 and inner wheel wall 2 cylindrical, and the rear wheel circular plate 5 and front wheel circular plate 6 annular, the complexity and cost of manufacturing and processing are reduced. At the same time, the cylindrical outer wheel wall 1 and inner wheel wall 2 provide uniform structural strength, resisting external forces and pressures, and improving stability.

[0036] like Figure 1 As shown, a flange is fixed at one end of the duct 9 near the dust cloud storage bag body 16. The flange is fixed to the dust cloud storage bag body 16. The duct 9 is connected and fixed to the dust cloud storage bag body 16 through the flange. The thickness of the dust collector wheel 13 is 3cm.

[0037] During use, the operator connects and secures the duct 9 to the dust cloud storage bag body 16 via the flange, ensuring a more secure connection and facilitating maintenance of the duct 9 connection point. Setting the thickness of the dust collection wheel 13 to 3cm improves its structural stability, reduces deformation, and thus aids in its operation.

[0038] The present invention also provides a method for generating a constant concentration dust cloud, the specific steps of which are as follows:

[0039] S1: The dust output per unit time is controlled by the dust-collecting wheel 13 and the stepper motor 12 to obtain a dust uniform release device;

[0040] S2: A production device for obtaining a standard concentration dust cloud through a fan 14, a gas mass flow controller 15, and a dust uniform release device.

[0041] S3: The pressure of the dust cloud storage bag body 16 is determined by the first air differential pressure switch 18 and the second air differential pressure switch 19, and the start and stop of the fan 14 and the stepper motor 12 are controlled. The starting pressure of the first air differential pressure switch 18 is set to h1. When the pressure of the dust cloud storage bag body 16 is less than h1, the first air differential pressure switch 18 issues a command, and the fan 14 and the stepper motor 12 start to work. The starting pressure of the second air differential pressure switch 19 is set to h2. When the pressure of the dust cloud storage bag reaches h2, the second air differential pressure switch 19 issues a command, and the fan 14 and the stepper motor 12 stop working.

[0042] S4: A dust cloud storage bag dust-generating fan 17 (whose motor and other electrical components are located outside the dust cloud storage bag body 16) is installed in the dust cloud storage bag body 16 to maintain the uniformity of the dust cloud in the dust cloud storage bag body 16.

[0043] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A constant concentration dust cloud generating device, comprising a dust storage box (11), characterized in that, The dust collection box (11) is funnel-shaped, with a dust-collecting wheel (13) below it. A stepper motor (12) is fixed to one side of the dust-collecting wheel (13), and an air duct (9) is located below the dust-collecting wheel (13). The air duct (9), dust collection box (11), dust-collecting wheel (13), and stepper motor (12) are respectively fixed to a frame. A gas mass flow controller (15) is fixed to one end of the air duct (9), and a fan (14) is fixed to the input end of the gas mass flow controller (15). A dust cloud storage bag body (16) is located at the other end of the air duct (9). A control panel (20) is fixed to the outer wall of the dust cloud storage bag body (16). The control panel (20) and the stepper motor (12) are connected. Electrically connected, the control panel (20) is electrically connected to the gas mass flow controller (15), the control panel (20) is electrically connected to the fan (14), a first air pressure differential switch (18) is fixed on one side of the outer wall of the dust cloud storage bag body (16), the first air pressure differential switch (18) is electrically connected to the control panel (20), a second air pressure differential switch (19) is fixed on the other side of the outer wall of the dust cloud storage bag body (16), the second air pressure differential switch (19) is electrically connected to the control panel (20), a dust cloud storage bag dust fan (17) is provided inside the dust cloud storage bag body (16), the dust cloud storage bag dust fan (17) is electrically connected to the control panel (20); The dust-collecting wheel (13) consists of an outer wheel wall (1), an inner wheel wall (2), thirty auxiliary wires (3), fifteen dust-collecting position quantitative dust bins (4), fifteen dust-collecting position quantitative dust bins (7), a rear wheel side circular plate (5), and a front wheel side circular plate (6). The volume of several dust-collecting position quantitative dust bins (4) and several dust-collecting position quantitative dust bins (7) is the same. Several auxiliary wires (3) are fixed to the inner wheel wall (2), several dust-collecting position quantitative dust bins (4), and several dust-collecting position quantitative dust bins (7), respectively. The outer wheel wall (1) is fixedly connected to the rear circular plate (5) and the front circular plate (6) of the wheel respectively. The outer wheel wall (1) has a dust receiving port (10) and a dust distribution port (8) at its top and bottom respectively. The dust distribution port at the bottom of the dust storage box (11) corresponds to the dust receiving port (10) of the outer wheel wall (1). The dust receiving port (10) covers the dust receiving position quantitative dust bin (4) and the adjacent dust distribution position quantitative dust bins (7) in front and behind. The bottom of the dust distribution port (8) of the outer wheel wall (1) is connected to the air duct (9). Several of the dust receiving position quantitative dust bins (4) and several of the dust distributing position quantitative dust bins (7) are evenly distributed along the outer edge of the dust distributing wheel (13), and the central angle of the several of the dust receiving position quantitative dust bins (4) and several of the dust distributing position quantitative dust bins (7) is 12°. Both the first air differential pressure switch (18) and the second air differential pressure switch (19) consist of an air differential pressure switch housing (21), an air differential pressure switch positive pressure input port (22), an air differential pressure switch negative pressure input port (23), an air differential pressure switch control circuit inlet (24), an air differential pressure switch pressure reading dial (25), and a pressure control pointer (26); the air differential pressure switch positive pressure input port (22) of the first air differential pressure switch (18) and the second air differential pressure switch (19) are fixedly connected to two Pitot tubes inside the dust cloud storage bag body (16); through the first air differential pressure switch (18) 8) The second differential air pressure switch (19) judges the pressure of the dust cloud storage bag body (16) and controls the start and stop of the fan (14) and the stepper motor (12). The starting pressure of the first differential air pressure switch (18) is set to h1. When the pressure of the dust cloud storage bag body (16) is less than h1, the first differential air pressure switch (18) issues a command and the fan (14) and the stepper motor (12) start working. The starting pressure of the second differential air pressure switch (19) is set to h2. When the pressure of the dust cloud storage bag reaches h2, the second differential air pressure switch (19) issues a command and the fan (14) and the stepper motor (12) stop working.

2. The constant concentration dust cloud generating device according to claim 1, characterized in that: The outer wheel wall (1) is cylindrical, the inner wheel wall (2) is cylindrical, the rear wheel plate (5) is annular, and the front wheel plate (6) is annular.

3. The constant concentration dust cloud generating device according to claim 1, characterized in that: The air duct (9) is fixed with a flange at one end near the dust cloud storage bag body (16). The flange is fixed to the dust cloud storage bag body (16), and the air duct (9) is connected and fixed to the dust cloud storage bag body (16) through the flange.

4. The constant concentration dust cloud generating device according to claim 1, characterized in that: The thickness of the dust-collecting wheel (13) is 3cm.

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