Dual light source dust concentration detection device and dust concentration detection method

Abstract

The application relates to a double-light-source dust concentration detection device and a dust concentration detection method, which comprise a first laser, a second laser, a light limiting element, a light focusing element, a photoelectric element, a master control unit and a light-shielded shell, a measurement reference straight line is arranged in the light-shielded shell, the light focusing element and the photoelectric element are arranged in the light-shielded shell, the light limiting element is arranged on the light-shielded shell, the photoelectric element, the light focusing element and the light limiting element are located on the measurement reference straight line, the photoelectric element can receive light information and convert the light information into an electric signal; the straight light emitted by the first laser is inclined to the measurement reference straight line, the second laser is located between the light limiting element and the light focusing element, and the straight light of the second laser is along the measurement reference straight line; during measurement, the light limiting element faces a dust detection area, the first laser and the second laser can both emit laser to the dust detection area, the scattered light is all projected to the light focusing element after passing through the light limiting element, and is focused on the photoelectric element.

Description

Technical Field

[0001] This invention relates to the field of dust detection technology, specifically to a dual-light source dust concentration detection device and a dust concentration detection method. Background Technology

[0002] With rapid industrialization, dust generation at manufacturing sites is constantly increasing, making dust concentration detection increasingly important. Backscattering is a common method for dust detection; however, current dust concentration readings using backscattering are affected by both dust-scattered light and background scattering. When the detection distance is long and the dust concentration is high, background scattering is negligible. But at close range and low dust concentration, the background scattering value may even exceed the dust-scattered light value, leading to significant errors in the dust detector's readings. Summary of the Invention

[0003] In view of the shortcomings of the prior art described above, the technical problem to be solved by the present invention is to provide a dual-light source dust concentration detection device and a dust concentration detection method to improve the accuracy of dust concentration detection, especially the detection accuracy under low dust concentration and close-range conditions.

[0004] To achieve the above objectives, the present invention provides a dual-source dust concentration detection device, comprising a first laser, a second laser, an optical confinement element, an optical focusing element, a photoelectric element, a main control unit, and a light-shielding housing. A measurement reference line is provided within the light-shielding housing. The optical focusing element and the photoelectric element are disposed within the light-shielding housing, and the optical confinement element is disposed on the light-shielding housing. The photoelectric element, optical focusing element, and optical confinement element are all located on the measurement reference line and arranged sequentially from back to front. The photoelectric element can receive light information and convert it into an electrical signal, and the photoelectric element is electrically connected to the main control unit. The optical confinement element can restrict the light passing through it. Field of view size; The first laser is mounted on the light-shielding housing. The straight light emitted by the first laser is inclined to the measurement reference line and does not pass through the light limiting element. The second laser is fixedly set inside the light-shielding housing and located between the light limiting element and the light focusing element. The straight light emitted by the second laser is along the measurement reference line and forward. During measurement, the light limiting element is oriented towards the dust detection area. Both the first laser and the second laser can emit lasers towards the dust detection area. The scattered light from the dust detection area is all projected onto the light focusing element after passing through the light limiting element. The light focusing element focuses the light onto the photoelectric element.

[0005] Furthermore, the light limiting element is an aperture.

[0006] Furthermore, the light focusing element is a parabolic mirror.

[0007] Furthermore, the optoelectronic element is a photodiode.

[0008] Furthermore, the first laser is fixed to the outside of the light-shielding shell.

[0009] Furthermore, the angle between the straight line emitted by the first laser and the measurement reference line is 13° to 17°.

[0010] The present invention also provides a method for detecting dust concentration, which uses the above-mentioned dual-light source dust concentration detection device, and includes:

[0011] A. Dust-free calibration and testing work includes the following steps:

[0012] A1. According to the measurement regulations, determine the direction of the measurement reference line of the dual-light source dust concentration detection device, with the light limiting element facing the background wall of the dust detection area, select a detection distance, and determine the detection position of the dual-light source dust concentration detection device;

[0013] A2. Single Calibration Test: Keeping the dual-light source dust concentration detection device in place, and in a dust-free environment in the dust detection area, perform the following test steps:

[0014] A21. The first laser is turned off, and the second laser is turned on, emitting laser light towards the dust detection area. The intensity value of the scattered light at this time is obtained through the light limiting element, the light focusing element and the photoelectric element, and transmitted to the main control unit, denoted as X.

[0015] A22. The second laser is turned off and the first laser is turned on, emitting laser light into the dust detection area. The intensity value of the scattered light at this time is obtained through the light limiting element, the light focusing element and the photoelectric element, and transmitted to the main control unit, denoted as Y.

[0016] A3. Move the dual-light source dust concentration detection device along the straight line of the measurement reference, repeat step A2, complete multiple calibration tests, and obtain multiple sets of data (X, Y);

[0017] A4. Based on multiple sets of data (X, Y), fit the functional relationship between Y and X to obtain Y = f(X);

[0018] B. Formal dust detection work includes the following steps:

[0019] B1. In accordance with the measurement regulations, determine the direction of the measurement reference line of the dual-light source dust concentration detection device, with the light limiting element facing the background wall of the dust detection area, select a detection distance, and determine the detection position of the dual-light source dust concentration detection device;

[0020] B2. Keeping the dual-light source dust concentration detection device in place, and in an environment with dust in the dust detection area, perform the following detection steps:

[0021] B21. The first laser is turned off and the second laser is turned on, emitting laser light towards the dust detection area. The intensity value of the scattered light at this time is obtained through the light limiting element, the light focusing element and the photoelectric element, and transmitted to the main control unit, denoted as Z.

[0022] B22. The second laser is turned off, and the first laser is turned on, emitting laser light towards the dust detection area. The intensity value of the scattered light at this time is obtained through the light limiting element, the light focusing element, and the photoelectric element, and transmitted to the main control unit, and recorded as the total scattered light intensity value P. 总 ;

[0023] B3. Data Processing: Based on the functional relationship between Z and the dust-free calibration test A, the dust scattered light intensity value P is obtained. 尘 =Pf(Z).

[0024] Furthermore, in step A3 of the dust-free calibration and testing operation A, the interval ΔL between two consecutive calibration and testing operations is 0.05 to 0.1 m.

[0025] Furthermore, in the smokeless calibration work A and the formal dust detection work B, the distance between the light limiting element of the dual-light source dust concentration detection device and the background wall of the dust detection area is 0 to 3 m.

[0026] As described above, the dual-light source dust concentration detection device and dust concentration detection method of the present invention have the following beneficial effects:

[0027] The dual-light source dust concentration detection device is calibrated and tested in a dust-free environment using a first laser and a second laser to obtain the functional relationship between the background scattered light under the illumination of the first and second lasers. Then, during the formal test, the background scattered light is obtained according to the functional relationship, and the obtained data is compensated and corrected to remove the influence of the background scattered light, thereby more accurately detecting the dust scattered light. This ensures that the dust concentration detection results are more accurate and meets the detection requirements under low dust concentration and close-range conditions. The dual-light source dust concentration detection device has a simple structure and the detection method is simple and reliable to operate. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the dual-light source dust concentration detection device of the present invention.

[0029] Figure 2 This is a schematic diagram of the operation of the second laser in the dual-light source dust concentration detection device of the present invention when it is turned on.

[0030] Figure 3This is a schematic diagram of the operation of the first laser of the dual-light source dust concentration detection device of the present invention when it is turned on.

[0031] Explanation of icon numbers

[0032] 1. Light-shielding housing

[0033] 11. Measuring the reference straight line

[0034] 2. Main Control Unit

[0035] 3. Optoelectronic components

[0036] 4. Optical focusing element

[0037] 5. Light limiting element

[0038] 6. First Laser

[0039] 7. Second laser

[0040] 8. Fasteners

[0041] 9. Dust Detection Area Detailed Implementation

[0042] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0043] It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings of this specification are merely for illustrative purposes to aid those skilled in the art in understanding and reading the content disclosed herein, and are not intended to limit the conditions under which the invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to the size, without affecting the effects and objectives achieved by the invention, should still fall within the scope of the technical content disclosed herein. Furthermore, the terms such as "upper," "lower," "left," "right," and "middle" used in this specification are merely for clarity and are not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention's implementation.

[0044] See Figures 1 to 3This invention provides a dual-light source dust concentration detection device, including a first laser 6, a second laser 7, a light confinement element 5, a light focusing element 4, a photoelectric element 3, a main control unit 2, and a light-shielding shell 1. A measurement reference line 11 is provided in the light-shielding shell 1. The light focusing element 4 and the photoelectric element 3 are fixedly disposed inside the light-shielding shell 1, and the light confinement element 5 is fixedly disposed on the light-shielding shell 1. The photoelectric element 3, the light focusing element 4, and the light confinement element 5 are all located on the measurement reference line 11 and are arranged sequentially from back to front. The photoelectric element 3 can receive light information and convert it into an electrical signal, and the photoelectric element 3 is electrically connected to the main control unit 2. The light confinement element 5 can constrain the field of view of the light passing through it. Laser 6 is mounted on light-shielding housing 1. The first laser 6 is mounted on light-shielding housing 1. The straight light emitted by the first laser 6 is inclined to the measurement reference line 11 and does not pass through the light limiting element 5. The second laser 7 is fixedly set inside the light-shielding housing 1 and is located between the light limiting element 5 and the light focusing element 4. The straight light emitted by the second laser 7 is along the measurement reference line 11 and forward. During measurement, the light limiting element 5 is oriented towards the dust detection area 9. Both the first laser 6 and the second laser 7 can emit lasers towards the dust detection area 9. The scattered light from the dust detection area 9 is all projected onto the light focusing element 4 after passing through the light limiting element 5. The light focusing element 4 focuses the light onto the photoelectric element 3.

[0045] The dual-light source dust concentration detection device of this invention can be used to measure the concentration of dust (also known as smoke, dust, etc.) in certain spaces, such as inside a flue, where the background wall is the flue wall. The dual-light source dust concentration detection device is based on the back reflection method, determining the dust concentration by measuring the intensity of the scattered light. During measurement, the measurement reference line 11 passes through the dust detection area 9, and the measurement direction of the dual-light source dust concentration detection device is the direction of the measurement reference line 11. See [link to relevant documentation]. Figure 2 and Figure 3Generally, during measurement, the measurement reference line 11 is perpendicular to the background wall of the dust detection area 9. However, the direction of the measurement reference line 11 can be determined based on the actual measurement conditions (including the shape of the background wall, measurement environment, etc.). The front light limiting element 5 faces the dust detection area 9. The first laser 6 and the second laser 7 emit laser light towards the dust detection area 9, generating scattered light. This scattered light passes through the light limiting element 5 and enters the light-shielding shell 1, where the field of view is constrained. All the scattered light passing through the light limiting element 5 is projected into the light focusing element 4. After being focused by the light focusing element 4, it is all received by the photoelectric element 3 and converted into corresponding electrical signals, which are then transmitted to the main control unit 2. The light-shielding shell 1 provides light shielding to its interior, preventing interference from other light sources. Detection is performed using the first laser 6 and the second laser 7 in both dusty and dust-free environments. Compensation and correction can be made based on the detection structure to remove background scattered light from the final detection results, thereby improving detection accuracy.

[0046] In this embodiment, see Figure 1 , Figure 2 and Figure 3 As a preferred design, the light limiting element 5 is an aperture, with its center located on the measurement reference line 11. The light emitted by the second laser 7 passes through the light limiting element 5, and its direction remains unchanged. The light focusing element 4 is a parabolic mirror, with its center located on the measurement reference line 11. The photoelectric element 3 is a photodiode, connected to the main control unit 2 via a wire. Other types of components can also be used for the photoelectric element 3, the light focusing element 4, and the light limiting element 5.

[0047] In this embodiment, see Figure 1 , Figure 2 and Figure 3 The first laser 6 is fixed to the outside of the light-shielding housing 1 by a fixing member 8 to maintain stability. The angle between the straight line of light emitted by the first laser 6 and the measurement reference line 11 is set according to the specific measurement situation, preferably 13° to 17°, and the emitted laser can illuminate the dust detection area 9. Of course, the first laser 6 is also installed inside the light-shielding housing 1.

[0048] The present invention also provides a method for detecting dust concentration, which uses the above-mentioned dual-light source dust concentration detection device, and includes:

[0049] A. Dust-free calibration and testing work includes the following steps:

[0050] A1. According to the measurement specifications, determine the direction of the measurement reference line 11 of the dual-light source dust concentration detection device. The light limiting element 5 should face the background wall of the dust detection area 9. Select a detection distance and determine the detection position of the dual-light source dust concentration detection device. That is, the measurement direction of the dual-light source dust concentration detection device during calibration should be consistent with that during formal measurement. Preferably, the measurement reference line 1111 is perpendicular to the simulated background wall.

[0051] A2. Single Calibration Test: Keep the dual-light source dust concentration detection device in place to ensure that dust detection area 9 is a dust-free environment. Specifically, when the dust concentration in dust detection area 9 is lower than a certain required value, it can be considered a dust-free environment. Then, perform the following testing steps:

[0052] A21. The first laser 6 is turned off, and the second laser 7 is turned on, emitting a laser beam towards the dust detection area 9. (See below) Figure 2 The intensity value of the scattered light at this time is obtained by the light limiting element 5, the light focusing element 4 and the photoelectric element 3, and transmitted to the main control unit 2, which is denoted as X. Since there is no dust in the environment, the measured value X can represent the background scattered light.

[0053] A22. The second laser 7 is turned off, and the first laser 6 is turned on, emitting a laser towards the dust detection area 9. This means that the measurement is performed using a laser at the normal detection angle. (See [reference]). Figure 3 The scattered light intensity value is obtained through the light limiting element 5, the light focusing element 4 and the photoelectric element 3 and transmitted to the main control unit 2, denoted as Y. Since there is no dust in the environment, the measured value Y also represents the background scattered light.

[0054] A3. Move the dual-light source dust concentration detection device along the measurement reference line 11, repeat step A2, and complete multiple calibration tests to obtain multiple sets of data (X, Y). When moving the dual-light source dust concentration detection device to perform multiple calibration tests, the interval ΔL between two consecutive calibration tests is preferably 0.05 to 0.1 m.

[0055] A4. Based on multiple sets of data (X, Y), the functional relationship Y = f(X) between Y and X is obtained by fitting. X and Y are the background scattered light under parallel laser in a dust-free environment and under tilted laser during formal testing, respectively. There is a certain functional relationship between the two. Therefore, after fitting the functional relationship Y = f(X) through multiple sets of data (X, Y), it can be used to calculate the background scattered light during formal testing.

[0056] B. Formal dust detection work includes the following steps:

[0057] B1. According to the measurement specifications, determine the direction of the measurement reference line 11 of the dual-light source dust concentration detection device. Orient the light limiting element 5 towards the background wall of the dust detection area 9. Select a detection distance and determine the detection position of the dual-light source dust concentration detection device. That is, the direction of the measurement reference line 11 at this time is the same as the direction of the measurement reference line 11 in the dust-free calibration detection work A.

[0058] B2. Keeping the dual-light source dust concentration detection device in place, and in an environment with dust in dust detection area 9, perform the following detection steps:

[0059] B21. The first laser 6 is turned off, and the second laser 7 is turned on, emitting a laser towards the dust detection area 9. (See below) Figure 2 The scattered light intensity value is obtained through the light limiting element 5, the light focusing element 4, and the photoelectric element 3, and transmitted to the main control unit 2, denoted as Z. Since the scattered light caused by dust can be ignored under the parallel light of the second laser 7 at low concentration and close distance, the detected value Z can be regarded as the background scattered light under the parallel light of the second laser 7.

[0060] B22. The second laser 7 is turned off, and the first laser 6 is turned on, emitting a laser towards the dust detection area 9. (See below) Figure 2 The scattered light intensity value is obtained through the light limiting element 5, the light focusing element 4, and the photoelectric element 3, and transmitted to the main control unit 2, which is recorded as the total scattered light intensity value P. 总 At this time, the total scattered light intensity value P 总 It consists of two parts, one of which is the background scattered light intensity value P. 背 Part of it is the intensity value P of dust-scattered light. 尘 That is, P 总 =P 背 +P 尘 .

[0061] B3. Data Processing: Based on the functional relationship between Z and the dust-free calibration test A, the dust scattered light intensity value P is obtained. 尘 =Pf(Z). In the dust-free calibration and testing work, the functional relationship Y = f(X) of the background scattered light under the illumination of the first laser 6 and the second laser 7 has been obtained. Therefore, in the detection result of step B22, the total scattered light intensity value P 总 =P 背 +P 尘 , where P 背 It can be obtained from the functional relationship between Z and the dust-free calibration test A, i.e., P 背 =f(Z), therefore P can be calculated. 尘=Pf(Z), and thus the dust concentration is obtained. The entire calculation process is automatically completed by the main control unit 2. The specific method for determining the dust concentration based on the dust scattered light intensity value is a known existing technique for dust concentration determination using the reflection method, and therefore will not be described in detail.

[0062] The dust concentration detection method of the present invention can meet the requirements of dust concentration measurement at close range under low concentration conditions. In the smokeless dust calibration work A and the formal dust detection work B, the distance between the light limiting element 5 of the dual light source dust concentration detection device and the background wall of the dust detection area 9 is 0 to 3 m.

[0063] As can be seen from the above, the dual-light source dust concentration detection device and dust concentration detection method of the present invention have the following beneficial effects:

[0064] 1. Calibration and testing are performed in a dust-free environment using the first laser 6 and the second laser 7 to obtain the functional relationship between the background scattered light under the illumination of the first laser 6 and the second laser 7. Then, during formal testing, the background scattered light is obtained based on the functional relationship, and the obtained data is compensated and corrected to remove the influence of the background scattered light, thereby more accurately detecting the dust scattered light. This ensures that the dust concentration detection results are more accurate and meets the detection requirements under low dust concentration and close-range conditions.

[0065] 2. The dual-light source dust concentration detection device has a simple structure and the detection method is simple and reliable to operate.

[0066] In summary, this invention effectively overcomes the various shortcomings of the prior art and has high industrial application value.

[0067] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A method for detecting dust concentration, characterized in that: A dual-source dust concentration detection device is used. The dual-source dust concentration detection device includes a first laser (6), a second laser (7), a light limiting element (5), a light focusing element (4), a photoelectric element (3), a main control unit (2), and a light-shielding shell (1). The light-shielding shell (1) is provided with a measurement reference line (11). The light focusing element (4) and the photoelectric element (3) are set inside the light-shielding shell (1). The light limiting element (5) is set on the light-shielding shell (1). The photoelectric element (3), the light focusing element (4), and the light limiting element (5) are all located on the measurement reference line (11) and are arranged sequentially from back to front. The photoelectric element (3) can receive light information and convert it into an electrical signal. The photoelectric element (3) is electrically connected to the main control unit (2). The light limiting element (5) can constrain the light passing through itself. The field of view of the light; the first laser (6) is mounted on the light-shielding shell (1), the straight light emitted by the first laser (6) is inclined to the measurement reference line (11) and does not pass through the light limiting element (5), the second laser (7) is fixedly set inside the light-shielding shell (1) and is located between the light limiting element (5) and the light focusing element (4), the straight light emitted by the second laser (7) is along the measurement reference line (11) and forward; during measurement, the light limiting element (5) is oriented towards the dust detection area (9), the first laser (6) and the second laser (7) can both emit lasers towards the dust detection area (9), and the scattered light from the dust detection area (9) is projected onto the light focusing element (4) after passing through the light limiting element (5), the light focusing element (4) focuses the light onto the photoelectric element (3); Dust concentration detection methods include: A. Dust-free calibration and testing work includes the following steps: A1. According to the measurement regulations, determine the direction of the measurement reference line (11) of the dual-light source dust concentration detection device, with the light limiting element (5) facing the background wall of the dust detection area (9), select a detection distance, and determine the detection position of the dual-light source dust concentration detection device; A2. Single calibration test: Keep the dual-light source dust concentration detection device in place, and in a dust-free environment in the dust detection area (9), perform the following test steps: A21. The first laser (6) is turned off and the second laser (7) is turned on, emitting a laser towards the dust detection area (9). The intensity value of the scattered light at this time is obtained through the light limiting element (5), the light focusing element (4) and the photoelectric element (3), and transmitted to the main control unit (2), denoted as X. A22. The second laser (7) is turned off and the first laser (6) is turned on, emitting a laser towards the dust detection area (9). The intensity value of the scattered light at this time is obtained through the light limiting element (5), the light focusing element (4) and the photoelectric element (3), and transmitted to the main control unit (2), denoted as Y. A3. Move the dual-light source dust concentration detection device along the measurement reference line (11) and repeat step A2 to complete multiple calibration tests and obtain multiple sets of data (X, Y). A4. Based on multiple sets of data (X, Y), fit the functional relationship between Y and X, Y=f(X). B. Formal dust detection work includes the following steps: B1. According to the measurement regulations, determine the direction of the measurement reference line (11) of the dual-light source dust concentration detection device, with the light limiting element (5) facing the background wall of the dust detection area (9), select a detection distance, and determine the detection position of the dual-light source dust concentration detection device; B2. Keeping the dual-light source dust concentration detection device in place, and in a dusty environment in the dust detection area (9), perform the following detection steps: B21. The first laser (6) is turned off and the second laser (7) is turned on, emitting a laser towards the dust detection area (9). The intensity value of the scattered light at this time is obtained through the light limiting element (5), the light focusing element (4) and the photoelectric element (3), and transmitted to the main control unit (2), denoted as Z. B22. The second laser (7) is turned off, and the first laser (6) is turned on, emitting laser light into the dust detection area (9). The scattered light intensity value at this time is obtained through the light limiting element (5), the light focusing element (4), and the photoelectric element (3), and transmitted to the main control unit (2), which is recorded as the total scattered light intensity value P. 总 ; B3. Data Processing: Based on the functional relationship Y=f(X) obtained from Z and the dust-free calibration test A, the dust scattered light intensity value P is obtained. 尘 =P 总 -f(Z).

2. The dust concentration detection method according to claim 1, characterized in that: In step A3 of the dust-free calibration and testing operation A, the interval ΔL between two adjacent calibration and testing operations is 0.05~0.1m.

3. The dust concentration detection method according to claim 1, characterized in that: In the dust-free calibration test A and the formal dust test B, the distance between the light limiting element (5) of the dual-light source dust concentration detection device and the background wall of the dust detection area (9) is 0~3m.

4. The dust concentration detection method according to claim 1, characterized in that: The light limiting element (5) is an aperture.

5. The dust concentration detection method according to claim 1, characterized in that: The light focusing element (4) is a parabolic mirror.

6. The dust concentration detection method according to claim 1, characterized in that: The optoelectronic element (3) is a photodiode.

7. The dust concentration detection method according to claim 1, characterized in that: The first laser (6) is fixed outside the light-shielding shell (1).

8. The dust concentration detection method according to claim 1, characterized in that: The angle between the straight line light emitted by the first laser (6) and the measurement reference line (11) is 13°~17°.

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