Anti-fouling device and light detector
By using an anti-contamination device in the optical detector, a positive pressure area is formed by airflow to block dirt on the lens surface, thus solving the problem of decreased detection accuracy caused by lens contaminant layer and improving lens cleanliness and detection accuracy.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- HANGZHOU KUANGXIN TECH CO LTD
- Filing Date
- 2025-05-22
- Publication Date
- 2026-05-26
AI Technical Summary
In high-temperature, high-humidity environments and environments with air pollutants, the lens surface of the optical detector is prone to the accumulation of a layer of pollutants, which leads to a decrease in detection accuracy.
An anti-fouling device, including a main body and a filter element, is adopted. Airflow is blown in through the air inlet to form a stable positive pressure area. The filter element filters and diffuses the airflow to block dirt on the lens surface and prevent the formation of a contaminant layer.
It effectively blocks dirt from the lens surface, ensuring lens cleanliness and improving the detection accuracy of the optical detector.
Smart Images
Figure CN224286696U_ABST
Abstract
Description
Technical Field
[0001] This application relates to testing devices, and more particularly to anti-fouling devices and light detectors. Background Technology
[0002] Optical detectors, such as near-infrared spectrometers, include lenses. Lenses are crucial components for light transmission. When the detection environment is consistently contaminated, such as in high temperature and humidity environments or with air pollutants (e.g., oily aerosols and suspended particulate matter), contaminants gradually accumulate on the lens surface, forming a contaminant layer. This contaminant layer causes a decrease in light transmittance and an increase in scattering effects, thus significantly reducing the detection accuracy of the optical detector. Utility Model Content
[0003] The purpose of this application is to disclose an anti-fouling device and a photodetector. The anti-fouling device helps to block dirt from the lens, ensuring the detection accuracy of the photodetector.
[0004] In a first aspect, this application discloses an anti-fouling device for preventing lens contamination, comprising a main body and a filter element. The main body is provided with an air inlet, and at least one of the main body and the filter element includes a mounting port for being covered by the lens; the filter element includes a through-hole cavity communicating with the mounting port, and the filter element cavity includes an air outlet communicating with the outside of the anti-fouling device; the filter element and the main body constitute a permeable airflow chamber, the airflow chamber communicating with the air inlet and the filter element cavity through permeability, and gradually decreasing in size along the direction from the mounting port towards the air outlet.
[0005] In some embodiments, the filter element is straight through, and the air outlet and the mounting port are distributed along the through direction of the filter element cavity.
[0006] In some embodiments, the airflow chamber includes an inner wall and an outer wall on which the air inlet is provided, one of the inner wall and the outer wall extending along the through direction of the filter cavity, and the other extending in a direction inclined to the through direction, so as to achieve the gradual reduction.
[0007] In some embodiments, along the depth direction of the airflow chamber, the distance between the centerline of the air inlet and the bottom of the airflow chamber is h, and the height of the airflow chamber is H, where 50% ≤ h / H ≤ 60%.
[0008] In some embodiments, there are multiple air inlets, which are evenly distributed around the circumference of the main body.
[0009] In some embodiments, the airflow chamber includes an inner wall and an outer wall on which the air inlet is disposed, and the airflow chamber includes at least one of the following features: a) the angle between one of the inner wall and the outer wall and the axis is t, 1 degree ≤ t ≤ 5 degrees, and the axis extends along the depth direction of the airflow chamber; b) the volume of the airflow chamber is V, 200,000 cubic millimeters ≤ V ≤ 250,000 cubic millimeters; c) along the depth direction perpendicular to the airflow chamber, the minimum width between the inner wall and the outer wall is w, 2 mm ≤ w ≤ 9 mm, and the maximum width is W, 5 mm ≤ W ≤ 15 mm.
[0010] In some embodiments, the filter element is a sintered filter element.
[0011] In some embodiments, the filter element includes filter pores with a pore size of a, 18 μm ≤ a ≤ 28 μm; and the filter element has a porosity of b, 40% ≤ b ≤ 60%.
[0012] In some embodiments, the anti-fouling device includes an upper sealing ring and a lower sealing ring; the lower sealing ring is located at the bottom of the airflow chamber and seals the gap between the filter element and the main body; the upper sealing ring is located at the top of the airflow chamber and seals the gap between the main body and the filter element.
[0013] In some embodiments, the main body includes a base and a housing, the housing including the air inlet and the base including the mounting port; the base is inserted into the housing and is threadedly connected to the housing.
[0014] Secondly, this application discloses a light detector, which includes any of the aforementioned anti-fouling devices and a detection component, wherein the anti-fouling device is connected to the detection component, and the detection component includes the lens.
[0015] In some embodiments, the detector includes a lens seal that seals the gap between the lens and the bottom of the detection assembly.
[0016] For the aforementioned anti-fouling device and optical detector, the external equipment provides compressed air to generate airflow. The airflow is blown into the airflow chamber through the air inlet. As the airflow chamber gradually decreases in size along the direction from the mounting port to the air outlet, the airflow diffuses rapidly and steadily within the airflow chamber, maintaining a high-speed flow. The diffused airflow undergoes secondary diffusion and filtration through the filter element, thereby ensuring the uniformity of the outflow gas velocity. After the airflow enters the filter element cavity, a stable positive pressure area is formed within the filter element cavity and below the lens. The positive pressure area effectively blocks dirt from the lens, preventing the formation of a contaminant layer on the lens, ensuring the cleanliness of the lens, and thus ensuring the detection accuracy of the optical detector. Attached Figure Description
[0017] Figure 1 This is a perspective view of a light detector according to this application;
[0018] Figure 2 This is an exploded view of a photodetector according to this application;
[0019] Figure 3 The photodetector of this application is in Figure 2 A further decomposition diagram based on this;
[0020] Figure 4 This is a schematic diagram of the anti-fouling device, the base plate of the photodetector, the lens, and the lens sealing ring of the present application in a disassembled state;
[0021] Figure 5 This is a cross-sectional view of the anti-fouling device of this application. Detailed Implementation
[0022] The technical solutions in the embodiments (or "implementations") of this application will be clearly and completely described herein with reference to the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements.
[0023] If the embodiments of this application contain terms relating to directional indications or positional relationships (such as up, down, left, right, front, back, inside, outside, top, bottom, center, vertical, horizontal, longitudinal, transverse, length, width, counterclockwise, clockwise, axial, radial, circumferential, etc.), such terms are only used to explain the relative positional relationships and movements between components in a specific posture (as shown in the attached figures); if the specific posture changes, the directional indications or positional relationships will also change accordingly. Furthermore, the terms "first" and "second" used in the embodiments of this application are only for descriptive convenience and should not be construed as indicating or implying relative importance.
[0024] See Figures 1 to 3 This application discloses a light detector, such as a near-infrared spectroscopy detector. The light detector includes any of the anti-fouling devices 10 and detection components 20 described in this application. The detection component 20 includes a lens 201. The anti-fouling device 10 is used to protect the lens 201 from environmental contamination; for example, it prevents the formation of a contaminant layer on the lens surface. Some structures of the anti-fouling device are described below.
[0025] See Figures 3 to 5The anti-fouling device 10 includes a main body 1 and a filter element 2. The main body 1 is provided with an air inlet 11. The structure of the air inlet 11 is not limited, and it is used to blow air into the interior of the anti-fouling device 10 to ultimately isolate the lens 201 from dirt. In this embodiment, the main body 1 is provided with a hole, and an air inlet connector 111 is inserted into the hole to form the air inlet 11. Of course, the air inlet connector can also be integrally formed with the hole to constitute the air inlet 11. Figure 5 In the design, the main body 1 is provided with a mounting opening 12 for being covered by the lens 201. The method of covering is not limited; for example, the main body 1 is provided with a positioning post 110. After the lens 201 and the mounting post 110 are installed, they cover the mounting opening 12. Alternatively, the mounting opening 12 can be provided on the filter element 2 (which can be understood as the base 13 in the figure being part of the filter element 2), or the mounting opening 12 can be provided on both the main body 1 and the filter element 2, that is, a part of the structure of the mounting opening 12 is provided on the main body 1, and another part of the structure of the mounting opening 12 is provided on the filter element 2.
[0026] See Figures 3 to 5 The filter element 2 includes a through-hole filtration cavity 21. The filter element cavity 21 communicates with the mounting port 12, and includes an air outlet 211 communicating with the outside of the anti-fouling device 10. The air outlet 211 can communicate directly with the outside of the anti-fouling device 10, or it can... Figure 5 As shown, the filter element 2 is connected to the outside of the anti-fouling device 10 through a hole at the bottom of the main body 1 (which can be understood as indirect connection). In some embodiments, the filter element 2 is straight through, that is, the filter element cavity 21 is a straight flow channel. In this case, the air outlet 211 and the mounting port 12 are distributed along the through direction of the filter element cavity 21. This arrangement allows the airflow to better fill the filter element cavity 21, thereby better blocking dirt and the lens 201.
[0027] See Figure 5 The filter element 2 and the main body 1 form an airflow chamber 3 with permeability. The airflow chamber 3 is connected to the air inlet 11 and is also connected to the filter element cavity 21 through the permeability, and gradually decreases in size along the mounting port 12 toward the air outlet 211.
[0028] See Figure 5The direction of airflow is indicated by dashed arrows. The advantages of the anti-fouling device are described as follows: External equipment provides compressed air to generate airflow. The airflow is blown into the airflow chamber 3 through the air inlet 11. As the airflow chamber 3 gradually decreases in size along the direction from the mounting port 12 to the air outlet 211, the airflow diffuses rapidly and steadily within the airflow chamber 3, maintaining a high-speed flow. The diffused airflow undergoes secondary diffusion and filtration through the filter element 2, thereby ensuring the uniformity of the outflow gas velocity. After the airflow enters the filter element cavity 21, a stable positive pressure area is formed within the filter element cavity 21 and below the lens 201. The positive pressure area effectively blocks dirt from the lens 201, preventing the formation of a contaminant layer on the lens 201, ensuring the cleanliness of the lens 201, and thus ensuring the detection accuracy of the optical detector.
[0029] See Figure 5 The airflow chamber 3 includes an inner wall 31 and an outer wall 32. In this application, the inner wall 31 is also the sidewall of the filter element 2, that is, the sidewall of the filter element cavity 21. The outer wall 32 is provided with the air inlet 11. The inner wall 31 extends along the through direction of the filter element cavity 21, and the outer wall 32 extends obliquely to the through direction to achieve the gradual reduction. It can also be understood that in the cross-section of the airflow chamber 3 along the through direction, one side (e.g., Figure 5 The airflow chamber 3 (on the left or right side) is a right-angled trapezoid. As an alternative to the "right-angled trapezoid," the outer wall 32 can extend along the through direction, and the inner wall 31 can extend in a direction inclined to the through direction to achieve the gradual reduction. In yet another embodiment, both the inner wall 31 and the outer wall 32 extend in a direction inclined to the through direction; in this case, the cross-section of the airflow chamber on one side is an isosceles trapezoid.
[0030] As described above, when the inner sidewall 31 extends along the through direction, the inner sidewall is also the sidewall of the filter element 2. In this way, the filter element 2 can be cylindrical, which is convenient for processing. The airflow diffused into the filter element cavity 21 is more uniform. The filter element 2 will not block light, so the anti-fouling device 10 can be adapted to different light sources, and has high adaptability.
[0031] See Figure 5 Along the depth direction of the airflow chamber 3, the distance between the center line of the air inlet 11 and the bottom of the airflow chamber 3 is h, and the height of the airflow chamber 3 is H, 50% ≤ h / H ≤ 60%, for example, 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, or 60%.
[0032] As described above, since 50% ≤ h / H ≤ 60%, the air pressure loss is reduced and the airflow speed blown into the filter element cavity 21 is increased. As a result, dirt can be better blocked from the lens 201. For example, it has a better blocking (retention) effect on dirt (oil suspended particles) with a particle size of less than or equal to 10 μm.
[0033] There may be only one air inlet 11. Alternatively, there may be multiple air inlets 11, evenly distributed circumferentially around the main body 1. In this application, there are three air inlets 11, evenly distributed circumferentially around the main body 1, with an included angle of 120 degrees between adjacent air inlets 11. Even with multiple air inlets 11, each air inlet 11 can still satisfy the h / H ratio. All air inlets 11 can be at the same height or unequal height, as long as the detection purpose is achieved and the detection accuracy is ultimately ensured.
[0034] As described above, since the air inlet 11 is evenly distributed along the circumference of the main body 1, the airflow in the airflow chamber 3 can diffuse more quickly and steadily, thus effectively blocking dirt from the lens 201.
[0035] In some embodiments, the airflow chamber 3 includes an inner wall 31 and an outer wall 32 on which the air inlet 11 is disposed, and the airflow chamber 3 includes at least one of the following features:
[0036] a) The angle between one of the inner wall 31 and the outer wall 32 and the axis is t, where 1 degree ≤ t ≤ 5 degrees. The axis extends along the depth direction of the airflow chamber 3, for example, 1 degree, 1.2 degrees, 1.5 degrees, 1.8 degrees, 2 degrees, 2.2 degrees, 2.5 degrees, 2.7 degrees, 3 degrees, 3.2 degrees, 3.5 degrees, 3.8 degrees, 4 degrees, 4.3 degrees, 4.5 degrees, 4.7 degrees, or 5 degrees.
[0037] b) The volume of the airflow chamber 3 is V, 200,000 cubic millimeters ≤ V ≤ 250,000 cubic millimeters, for example, 200,000 cubic millimeters, 205,000 cubic millimeters, 208,000 cubic millimeters, 210,000 cubic millimeters, 213,000 cubic millimeters, 215,000 cubic millimeters, 217,000 cubic millimeters, 220,000 cubic millimeters, 230,000 cubic millimeters, 233,000 cubic millimeters, 235,000 cubic millimeters, 238,000 cubic millimeters, 240,000 cubic millimeters, 243,000 cubic millimeters, 245,000 cubic millimeters, 248,000 cubic millimeters, or 250,000 cubic millimeters.
[0038] c) Along the depth direction perpendicular to the airflow chamber 3, the minimum width between the inner wall 31 and the outer wall 32 is w, 2mm≤w≤9mm, for example, 2mm, 2.2mm, 2.5mm, 2.8mm, 3mm, 3.2mm, 3.5mm, 3.8mm, 4mm, 4.3mm, 4.5mm, 4.7mm, 5mm, 5.2mm, 5.5mm, 5.8mm, 6mm, 6.2mm, 6.5mm, 6.8mm, 7mm, 7.2mm, 7.5mm, 7.7mm, 8mm, 8.2mm, 8.5mm, 8.8mm, or 9mm. The maximum width is W, where 5mm ≤ W ≤ 15mm, for example, 5mm, 5.2mm, 5.5mm, 5.8mm, 6mm, 6.3mm, 6.5mm, 6.8mm, 7mm, 7.2mm, 7.5mm, 7.8mm, 8mm, 8.2mm, 8.5mm, 8.8mm, 9mm, 9.2mm, 9.5mm, 9.8mm, 10mm, 10.3mm, 10.8mm, 11mm, 11.3mm, 11.5mm, 11.8mm, 12mm, 12.3mm, 12.5mm, 12.7mm, 13mm, 13.2mm, 13.5mm, 13.8mm, 14mm, 14.2mm, 14.5mm, 14.7mm, or 15mm.
[0039] As described above, the airflow chamber 3 satisfies at least one of features a, b, and c, which reduces air pressure loss and increases the speed of the airflow blown into the filter element cavity 21. Consequently, it can better fill the filter element cavity 21 and better block dirt from the lens 201. For example, it has a better blocking (retention) effect on dirt (oil suspended particles) smaller than or equal to 10 μm.
[0040] In some embodiments, the filter element 2 is a sintered filter element, for example, made by sintering stainless steel powder. In other embodiments, filter elements with other structures that can achieve the same function can also be used, and the material of the filter element 2 is not limited to metal.
[0041] As described above, since the filter element 2 is a sintered filter element, the filter pores of the sintered filter element are uniform, ensuring the uniformity of the gas velocity flowing into the filter element cavity 21, which is conducive to forming a stable positive pressure area. Thus, dirt is effectively blocked from the lens 201. Furthermore, the sintered filter element can also make the airflow diffuse evenly to the outside of the filter element cavity 21 and the anti-fouling device 10, and the flow velocity is basically consistent within a certain range, thereby reducing airflow noise.
[0042] In some embodiments, the filter element 2 includes filter pores with a pore size of a, 18μm≤a≤28μm, for example, 18μm, 19μm, 20μm, 21μm, 22μm, 23μm, 24μm, 25μm, 26μm, 27μm, or 28μm; and a porosity of b, 40%≤b≤60%, for example, 40%, 43%, 45%, 48%, 49%, 50%, 52%, 55%, 57%, or 60%.
[0043] As described above, if the filter pores meet any of the above conditions, the airflow speed from the filter element 2 can be effectively increased, and the filter element cavity 21 can be better filled to increase the blocking range. For example, there is also airflow in the central area of the filter element cavity 21. Thus, it can effectively block dirt (such as oil and / or dust with a particle size ≤10μm). In some cases, even after continuous operation for a long time in a high-concentration oil environment, its protection efficiency against dirt (such as oil) on the lens 201 can still reach 99%.
[0044] See Figure 3 , Figure 4 and Figure 5 The anti-fouling device includes an upper sealing ring 4 and a lower sealing ring 5; the lower sealing ring 5 is located at the bottom of the airflow chamber 3, sealing the gap between the filter element 2 and the main body 1. The upper sealing ring 4 is located at the top of the airflow chamber 3, sealing the gap between the main body 1 and the filter element 2.
[0045] As described above, the upper sealing ring 4 and the lower sealing ring 5 are used to seal the airflow chamber 3, reducing gas leakage and ensuring the airflow velocity in the airflow chamber 3. This, in turn, creates a more stable positive pressure area, effectively blocking dirt from the lens 201.
[0046] See Figure 3 , Figure 4 and Figure 5 The main body 1 includes a base 13 and a housing 14. The base 13 and the housing 14 can be integrally formed or assembled together. The housing 14 includes the air inlet 11. The base 13 includes the mounting port 12. The base 13 is inserted into the housing 14 and is connected to the housing 14 by threads.
[0047] As described above, the base 13 is inserted into the housing 14 and connected to the housing 14 by a thread. This ensures the sealing performance of the airflow chamber 3, ultimately creating a stable positive pressure area in the filter cavity 21. The positive pressure area effectively blocks dirt from the lens 201, preventing the formation of a contaminant layer on the lens 201, ensuring the cleanliness of the lens 201, and thus ensuring the detection accuracy of the photodetector.
[0048] See Figure 3 and Figure 4 The detector includes a lens sealing ring 202, which seals the gap between the lens 201 and the bottom of the detection assembly 20. More specifically, the bottom of the detection assembly 20 is a base plate 203. A locking screw 204 passes through the base 13 and locks to the base plate 203 to clamp the lens 201 and the lens sealing ring 202, thereby sealing the gap between the lens 201 and the bottom of the detection assembly 20.
[0049] As described above, the lens sealing ring 202 seals the gap between the lens 201 and the bottom of the detection component 20. This enhances the sealing performance of the filter cavity 21 and allows a positive pressure area to be formed inside the filter cavity 21. This effectively isolates the lens 201 from dirt and ensures the detection accuracy of the photodetector.
[0050] It should be noted that the technical solutions or features described in the above embodiments can be combined or supplemented with each other without conflict. The scope of protection of this application is not limited to the precise structures described in the above embodiments and shown in the accompanying drawings; all modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.
Claims
1. A contamination prevention device for preventing contamination of a lens, characterized in that, The anti-fouling device includes a main body and a filter element, wherein: The main body is provided with an air inlet, and at least one of the main body and the filter element includes a mounting port for being covered by a lens; The filter element includes a through-hole, which is connected to the mounting port and includes an air outlet that is connected to the outside of the anti-fouling device. The filter element and the main body form an airflow chamber with permeability. The airflow chamber is connected to the air inlet and is also connected to the filter element cavity through the permeability. The size of the airflow chamber gradually decreases along the direction from the mounting port to the air outlet.
2. The anti-fouling device according to claim 1, characterized in that, The filter element is straight through, and the air outlet and the mounting port are distributed along the through direction of the filter element cavity.
3. The anti-fouling device according to claim 2, characterized in that, The airflow chamber includes an inner wall and an outer wall with the air inlet. One of the inner wall and the outer wall extends along the through direction of the filter cavity, and the other extends in a direction inclined to the through direction, so as to achieve the gradual reduction.
4. The anti-fouling device according to claim 1, characterized in that, Along the depth direction of the airflow chamber, the distance between the centerline of the air inlet and the bottom of the airflow chamber is h, and the height of the airflow chamber is H, 50% ≤ h / H ≤ 60%; And / or, there are multiple air inlets, which are evenly distributed circumferentially on the main body.
5. The anti-fouling device according to claim 1, characterized in that, The airflow chamber includes an inner wall and an outer wall on which the air inlet is provided, and the airflow chamber includes at least one of the following features: a) The angle between one of the inner wall and the outer wall and the axis is t, where 1 degree ≤ t ≤ 5 degrees, and the axis extends along the depth direction of the airflow chamber; b) The volume of the airflow chamber is V, where 200,000 cubic millimeters ≤ V ≤ 250,000 cubic millimeters; c) Along the depth direction perpendicular to the airflow chamber, the minimum width between the inner wall and the outer wall is w, 2mm≤w≤9mm, and the maximum width is W, 5mm≤W≤15mm.
6. The anti-fouling device according to claim 1, characterized in that, The filter element is a sintered filter element; And / or, the filter element includes filter pores, the pore diameter of which is a, 18μm≤a≤28μm; the porosity of the filter element is b, 40%≤b≤60%.
7. The anti-fouling device according to claim 1, characterized in that, The anti-fouling device includes an upper sealing ring and a lower sealing ring; the lower sealing ring is located at the bottom of the airflow chamber and seals the gap between the filter element and the main body; The upper sealing ring is located at the top of the airflow chamber and seals the gap between the main body and the filter element.
8. The anti-fouling device according to claim 1, characterized in that, The main body includes a base and a housing, the housing includes the air inlet, and the base includes the mounting port; the base is inserted into the housing and is connected to the housing by threads.
9. A light detector, characterized in that, The optical detector includes an anti-fouling device and a detection component as described in any one of claims 1 to 8, wherein the anti-fouling device is connected to the detection component, and the detection component includes the lens.
10. The optical detector according to claim 9, characterized in that, The detector includes a lens sealing ring that seals the gap between the lens and the bottom of the detection assembly.