Sensor arrangement for detecting particles

Abstract

Sensor arrangement (1) for detecting particles, comprising: a housing (11) having an air flow channel (11a) through which air flows from the outside of the housing (11) into the housing; a fan drive (15) which is mounted inside the housing (11) and is arranged to flow the air from the outside of the housing (11) into the air flow channel (11a); a light source (21) arranged to emit light to allow the light to intersect with the air flowing into the air flow channel (11a); and a light receiving sensor (25) arranged to receive light scattered by dust contained in the air flowing through the air flow channel (11a), wherein the air flow channel (11a) is designed such that a region in which the air flows into the housing (11) from the outside thereof has a cross-sectional area which is larger than the cross-sectional area of ​​a region in which the light emitted by the light source (21) intersects with flowing air, wherein the housing (11) further comprises: a light path section (22) communicating with the air flow channel (11a) for radiating the light emitted by the light source (21) to the air flow channel (11a), wherein a dust collecting section (23) is formed on the light path section (22), and the dust collecting section (23) is a space formed in a direction perpendicular to the light path section (22), wherein dust collecting sections (23) are provided in multiples to form a plurality of dust collecting sections (23), and wherein the plurality of dust collecting sections (23) are formed at predetermined intervals along the light path section (22), and wherein the plurality of dust collecting sections (23) are shaped so that the cross-sectional area of ​​each of the plurality of dust collecting sections (23) becomes smaller, as the distance between the light source (21) and each of the plurality of dust collecting sections (23) increases.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to Korean patent application KR 10 2020 0 033 619 A, filed on September 20, 2018, the entire contents of which are incorporated herein by reference. BACKGROUND OF REVELATIONArea of ​​Revelation

[0002] The present invention relates to a particle detection sensor for detecting the concentration of particles contained in the air, and more particularly to a particle detection sensor assembly which prevents dust from being adsorbed onto a light source or a light receiving element, thereby preventing the output value from being lowered by the adsorption of dust, and from which adsorbed dust need not be removed regularly. Description of the state of the art

[0003] Since airborne particles can cause various respiratory diseases, airborne particles must be limited to an appropriate level or less.

[0004] Particularly recently, the harmful effects of ultrafine particles (PM2.5) with a diameter of 2.5 µm or less have become widely known, and interest in airborne particles has continued to increase.

[0005] In an enclosed space, such as the interior of a vehicle, it is possible to control the concentration of particles in the room air by detecting the concentration of particles in the room air and cleaning the air with an air purifier.

[0006] Fig. 1 illustrates a prior art particle detection sensor assembly 100. A duct, through which air flows from the outside through an inlet 111a into the duct, is formed in a casing 111. A fan motor 115 is provided to allow air to flow into the casing 111, so that when the fan motor 115 operates, dust-laden air flows into the casing from the outside. Furthermore, a light source 121 and a light-receiving sensor 125 that receives light emitted by the light source 121 are provided in the casing 111. Infrared rays emitted from the light source 121 are scattered by dust in the air while passing through the air flowing into the duct. Infrared rays scattered by dust pass through a bandpass filter 123 that blocks ultraviolet rays and visible rays and are then collected by a condenser lens 124.Thus, the infrared rays received by the light receiving sensor 125 are determined to measure the concentration of particles in the air.

[0007] However, the conventional prior art particle detection sensor assembly 100 has a problem that, upon prolonged use of the assembly, dust is adsorbed onto components that come into contact with flowing air, such as a transparent plate for protecting the light source 121, the bandpass filter 123, and the like.

[0008] The amount of light received by the light receiving sensor 125 is reduced due to the adsorption of particles, and thus there is a problem that the performance of the particle detection sensor assembly 100 deteriorates.

[0009] Furthermore, in order to solve the problem caused by the adsorption of particles, there is a disadvantage that the sensor assembly 100 for detecting particles needs to be disassembled at regular intervals to remove particles.

[0010] For further prior art, reference can be made to DE 10 2016 216 074 A1, which shows a sensor arrangement for detecting particles, comprising a fan drive, an air flow duct, a light source and a light receiving sensor.

[0011] Further prior art is shown in DE 10 2006 029 899 B4, EP 2 848 913 A1 and US 11 035 777 B2.

[0012] The information disclosed in this "Background of the Invention" section is provided for the sole purpose of facilitating an understanding of the general background of the invention and is not intended as an acknowledgement or any form of suggestion that this information constitutes prior art already known to a person skilled in the art. SHORT SUMMARY

[0013] Various aspects of the present invention are directed to providing a sensor assembly for detecting particles that is configured to prevent particles contained in the air flowing therein from being adsorbed and to maintain sensitivity even after prolonged use.

[0014] To achieve the above-described object, a sensor assembly for detecting particles according to the present invention comprises a housing in which an air flow channel is formed through which air flows from the outside thereof, a fan motor arranged inside the housing for flowing air from the outside into the air flow channel, a light source that emits light to allow light to intersect with the air flowing into the air flow channel, and a light receiving sensor that is configured to receive light scattered by dust contained in the air flowing through the air flow channel, wherein the air flow channel may be configured such that a region into which air flows from the outside has a cross-sectional area larger than that of a region in which light emitted by the light source intersects with flowing air,wherein the housing further comprises: a light path portion communicating with the air flow channel for radiating the light emitted from the light source to the air flow channel, wherein the dust collecting portion is formed on the light path portion, and the dust collecting portion is a space formed in a direction perpendicular to the light path portion, wherein a dust collecting portion is provided in multiples to form a plurality of dust collecting portions, and wherein the plurality of dust collecting portions are formed at predetermined intervals along the light path portion, and wherein the plurality of dust collecting portions are shaped such that the cross-sectional area of ​​each of the plurality of dust collecting portions becomes smaller as the distance between the light source and each of the plurality of dust collecting portions increases.

[0015] The air flow channel may include an inlet portion into which air flows from the outside, the inlet portion having a predetermined cross-sectional area over a predetermined length; and a detection portion connected to the inlet portion, which has a smaller cross-sectional area than the inlet portion and intersects with light emitted from the light source.

[0016] In a throat portion connecting the inlet portion and the detection portion, an air flow direction in the air flow passage can be changed from a width direction of the housing to a height direction of the housing.

[0017] The neck portion may be formed such that an inner wall gradually approaches an outer wall facing the housing to reduce the cross-sectional area.

[0018] The detection section may be formed to have a cross-sectional area that is reduced in the direction of air flow and then increased.

[0019] The air flow channel may have a minimum cross-sectional area in a region where the air flow channel communicates with the light path section.

[0020] The dust collection sections are designed so that they each have different cross-sectional areas.

[0021] A light extinguishing portion may be formed coaxially with the light path portion to allow light passing through and incident on the air flow channel to be extinguished therein.

[0022] The light extinguishing portion may include a reflecting surface configured to reflect light that has entered the light extinguishing portion through the air flow passage; and a plurality of inclined surfaces repeatedly configured to extinguish light reflected at the reflecting surface.

[0023] The light receiving sensor may be arranged in a direction perpendicular to the light path section.

[0024] The light source can emit a laser beam that radiates onto the air flowing into the air flow channel.

[0025] The light receiving sensor may be a photodiode that receives light scattered by dust entering the air flow channel, and a controller is configured to determine the concentration of dust by processing a signal output from the light receiving sensor.

[0026] The housing may be provided with a cover configured to close the interior of the housing, and the cover may have an inlet formed therein that communicates with the air flow channel to allow air to flow from the outside into the air flow channel.

[0027] The cover may be provided with an air inlet opening formed thereon for flowing air from an air vent that blows air into the interior of the vehicle into the housing and a contact pad designed to seal the housing.

[0028] The housing may have a mounting portion formed in one side thereof, and a fastener may pass through the mounting hole to secure the housing to the air vent.

[0029] The fastening member may be a fastening bolt, and the air vent may have a fastening portion formed thereon so as to protrude, and the fastening bolt is screw-coupled to the fastening portion.

[0030] The apparatus of the present invention has other features and advantages which will be apparent from or particularly pointed out in the accompanying drawings incorporated herein and in the following detailed description, which together serve to explain certain principles of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a cross-sectional view illustrating, by way of example, the interior of a sensor assembly for detecting particles according to the prior art. Fig. 2 is a perspective view illustrating an exemplary sensor assembly for detecting particles according to an exemplary embodiment of the present invention. Fig. 3 is a sectional view taken along line II in Fig. 2 and illustrates the interior of the sensor assembly for detecting particles according to an exemplary embodiment of the present invention. Fig. 4 is a cross-sectional view along the line II-II in Fig. 3. Fig. 5 is a perspective view illustrating, by way of example, a path along which air flows into the sensor assembly for detecting particulates according to an exemplary embodiment of the present invention. Fig. 6 is a cross-sectional view exemplifying a state in which air flows into the sensor assembly for detecting particulate matter according to an exemplary embodiment of the present invention. Fig. 7 is a cross-sectional view taken along line III-III in Fig. 6. Fig. 8 is a cross-sectional view illustrating in detail, by way of example, an area where air flow and infrared rays intersect in the sensor assembly for detecting particles according to an exemplary embodiment of the present invention. Fig. 9 is a cross-sectional view illustrating, in the sensor assembly for detecting particulate matter according to an exemplary embodiment of the present invention, a method in which dust is collected in a dust collecting section and a state in which light is extinguished in a light extinguishing section. Fig. 10 is a cross-sectional view exemplifying an example in which the particulate matter sensor assembly according to an exemplary embodiment of the present invention is disposed on a side of a vehicle.

[0031] It should be understood that the accompanying drawings are not necessarily to scale and present a somewhat simplified representation of various features illustrating the basic principles of the invention. The specific design features of the present invention as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes, will be determined in part by the particular intended application and use environment.

[0032] In the figures, reference numerals designate the same or equivalent parts of the present invention in the several figures of the drawing. DETAILED DESCRIPTION

[0033] Reference will now be made in detail to various embodiments of the present invention(s), examples of which are illustrated in the accompanying drawings and described below. While the invention(s) will be described in connection with exemplary embodiments of the present invention, it is to be understood that the present description is not intended to limit the invention(s) to these exemplary embodiments. On the contrary, the invention(s) are intended to cover not only the exemplary embodiments of the present invention, but also various alternatives, modifications, equivalents, and other embodiments that may be included within the spirit and scope of the present invention as defined by the appended claims.

[0034] In the following, a sensor arrangement for detecting particles according to an exemplary embodiment of the present invention will be explained in detail with reference to the accompanying drawings.

[0035] A sensor assembly 1 for detecting particles according to an exemplary embodiment of the present invention includes a housing 11 in which an air flow channel 11a is formed through which air flowing therein from the outside flows, a fan motor 15 disposed inside the housing 11 for flowing air from the outside into the air flow channel, a light source 21 that emits light to allow light to intersect with air flowing into the air flow channel 11a, and a light receiving sensor 25 configured to receive light scattered by dust contained in the air flowing through the air flow channel 11a.

[0036] The air flow passage 11a into which air flows is formed inside the housing 11, and other components, which will be described later, are arranged in the housing.

[0037] The air duct 11a is formed within the housing 11 so that air flowing therein from the outside can flow therein. The air flow duct 11a includes an inlet portion 11aa into which air flows from the outside, a detection portion 11ab configured to detect dust contained in the air flowing into the air flow duct 11a, and a throat portion 11ac connecting the inlet portion 11aa and the detection portion 11ab.

[0038] The inlet portion 11aa forms a vortex of air flowing in from the outside within the inlet portion 11aa to prevent dust with a relatively large particle size from entering the detection portion 11ab. The inlet portion 11aa is formed to have a predetermined cross-sectional area over a predetermined length in a direction of the casing 11. The inlet portion 11aa is then reduced in cross-sectional area and is connected to the detection portion 11ab through the neck portion 11ac, which changes an air flow direction to a direction perpendicular to the inlet portion 11aa. A flow direction of the air flowing into the inlet portion 11aa in a height direction of the casing 11 is changed to a width direction of the casing 11 in the inlet portion 11aa.

[0039] A cross-sectional area connected to the inlet portion 11aa is smaller than that of the inlet portion 11aa, and the throat portion 11ac enables a direction of the air flow channel 11a to change from the width direction to the height direction of the housing 11. Therefore, a vortex is generated in the flow of air flowing into the inlet portion from the outside in the inlet portion 11aa, so that dust with a relatively large diameter (about 10 μm or more) remains within the inflow portion 11aa, while dust with a small diameter is moved to the detection portion 11ab via the throat portion 11ac.

[0040] Since dust with a large particle size is blocked mainly in the inlet portion 11aa as described above, the light source 21 or the light receiving sensor 25 is prevented from being contaminated by dust with a large particle size, and thereby the durability of the particle detection sensor assembly 1 can be increased.

[0041] Furthermore, by removing dust with a large particle size in the inlet section 11aa and allowing dust with a small particle size to flow into the detection section 11ab, a particle size of dust that can be measured in the detection section 11ab can be controlled. For example, by blocking dust of PM10 or more in the inlet 11aa, a concentration of ultrafine particles of, for example, PM2.5 can be measured in the detection section 11ab.

[0042] The detection section 11ab is connected to the inlet section 11aa via the throat section 11ac. The detection section 11ab is configured to allow air to flow linearly to detect dust contained in the air flowing into the air flow channel 11a. At this time, in order to prevent dust from being adsorbed on the light source 21 described later, the flow velocity of the air is maximized in a region where light is radiated from the light source 21. When the flow rate of the air is increased, the dust is difficult to separate from the flowing air. Accordingly, by increasing the flow rate of the air in the air flow channel 11a, dust is prevented from moving toward the light source 21.Meanwhile, in order to increase the flow rate of air flowing through the air flow passage 11a, the air flow passage 11a is formed to have a cross-sectional area that decreases in the air flow direction and then increases. When the cross-sectional area of ​​an intermediate portion of the detection portion 11ab is smaller than that of both an inlet and an outlet, the air flow rate in the intermediate portion increases, and thus dust can be prevented from moving toward the light source 21. That is, the detection portion 11ab is formed so that the cross-sectional area of ​​the detection portion decreases from the inlet portion 11aa in the air flow direction, becomes minimal in a region where the air flow intersects with light emitted from the light source 21, and then increases again.When air flows into the detection section 11ab, the flow rate of the air reaches a maximum value in a region where the cross-sectional area is the smallest, and thus dust can be prevented from being moved from the air flow channel 11a to the light source 21.

[0043] In the neck portion 11ac, the cross-sectional area of ​​the inlet portion 11aa is changed to decrease, and the direction of the air flow passage 11a is changed. The neck portion 11ac enables the direction of the air flow passage 11a to change from the height direction to the width direction of the housing 11. Further, the neck portion 11ac is connected to the detection portion 11ab in a state where its cross-sectional area is gradually reduced. The neck portion 11ac is formed so that its inner wall gradually approaches its outer wall facing the housing 11 to gradually reduce the cross-sectional area.In other words, in the neck portion 11ac of the air flow passage 11a, only the direction of the outer wall facing the case is changed from the width direction of the case 11 to the height direction thereof, but the inner wall gradually approaches the outer wall, and at the same time, the direction of the inner wall is changed from the width direction to the height direction of the case 11.

[0044] A cover 12 is connected to the housing 11 to close the interior of the housing 11. On one side of the cover 12, an inlet 12a is formed, passing through the cover 12, so that air can flow from the outside into the air flow channel 11a.

[0045] A contact pad 13 is attached to the cover 12 to seal an area through which air flows into the housing when the particle sensing sensor assembly of the present invention is attached.

[0046] The fan motor 15 is arranged on an outlet side of the air flow duct 11a in the housing 11 to allow air to flow from the outside into the air flow duct 11a.

[0047] A connector 17 configured to supply the power required to operate the light source 21 and the fan motor 15 and to output the measured value output by the light receiving sensor 25 or the determined concentration value of the particles is attached to one side of the housing 11.

[0048] The light source 21 is arranged in the housing 11 to emit light used for detecting particles. In an exemplary embodiment of the present invention, a laser module configured to emit a laser beam when the laser beam is scattered by particles in the air flow channel 11a is used as the light source 21, and the light receiving sensor measures the scattered light to detect particles contained in the air.

[0049] A light path portion 22 is a path along which light emitted from the light source radiates. The light path portion 22 is formed in the housing 11 and extends perpendicular to the air flow passage 11a, and an end portion of the light path portion 22 communicates with the air flow passage 11a. At this time, the light path portion is formed such that a diameter of the area where the light path portion 22 communicates with the air flow passage 11a prevents air from flowing to the light source 21 while transmitting the light emitted from the light source.For example, by making the diameter of the region where the light path portion 22 communicates with the air flow passage 11a on the order of 1 mm, although light emitted from the light source 21 passes through the present region and radiates toward the air flow passage 11a, no air in the light path portion 22 flows from the air flow passage 11a to the light source 21, and thus dust contained in flowing air can be prevented from flowing into the light source.

[0050] A dust collection section 23 is formed on the light path section 22 in a direction perpendicular to the light path section 22. The dust collection section 23 is a space formed in a direction perpendicular to an axis of the light path section 22, and even if particles enter the light path section 22, the particles are collected and accumulated in the dust collection unit 23 to prevent the particles from being moved to the light source 21.

[0051] The plurality of dust collecting portions 23 are formed at predetermined intervals in a longitudinal direction of the light path portion 22. Since the plurality of dust collecting portions 23 are formed in the light path portion 22, a region between the light source 21 and the air flow passage 11a has a configuration in which a cross section of the light path portion 22 and the dust collecting portions 23 is repeatedly varied. Therefore, even if dust enters the light path portion 22 from the air flow passage 11a, dust is collected in the dust collecting portions 23 to prevent dust from flowing toward the light source 21.

[0052] A light extinguishing portion 24 is formed coaxially with the light path portion 22. The light extinguishing portion 24, with a space formed therein, is formed on a side opposite the area where the air flow passage 11a communicates with the light path portion 22. The light extinguishing portion 24 allows light passed through the air flow passage 11a to be extinguished therein. If light that is not scattered by dust is reflected and incident on the light receiving sensor 25, an error occurs in the measured value of the light receiving sensor 25. Therefore, the light extinguishing portion 24 allows light to be extinguished therein, so that light that is not scattered by particles and passed through the air flow passage 11a is reflected and does not incident on the light receiving sensor 25.

[0053] Referring to an internal structure of the light extinguishing portion 24 (see Fig. 9), the light extinguishing portion 24 includes a reflecting surface 24a configured to reflect the light passed through the air flow channel 11a into the light extinguishing portion 24, and an inclined surface 24b configured to extinguish the light reflected by the reflecting surface 24a. The reflecting surface 24a is formed inclined with respect to the light path portion 22.

[0054] Light passing through the light path portion 22 is reflected by the reflecting surface 24a to allow light emitted from the light source 21 to be reflected inside to the light extinguishing portion 24. The plurality of inclined surfaces 24b are repeatedly formed in the light extinguishing portion 24. The inclined surface 24b is formed to have a low height, and a plurality of inclined surfaces having such a structure are repeatedly formed. Since the repeatedly formed inclined surfaces 24b are arranged in a sawtooth shape in cross section, light incident on the light extinguishing portion 24 is extinguished, and thus reflected light is prevented from being incident on the light receiving sensor 25.

[0055] The reflecting surface 24a and the inclined surface 24b are not formed to be smooth like a mirror surface. Since the light extinguishing portion 24 is the element in which light is extinguished, the interior of the light extinguishing portion 24 may not necessarily be formed to be smooth like a mirror surface.

[0056] The light receiving sensor 25 is arranged in the housing 11. The light receiving sensor 25 may be a photodiode that outputs an electrical signal upon detecting light. The light receiving sensor 25 is arranged in a direction perpendicular to the light path section 22 (see Fig. 4), so that when light scattered by particles contained in the air flowing into the air flow channel 11a is incident on the light receiving sensor, the light receiving sensor outputs a signal proportional to the scattered light.

[0057] The signal output by the light receiving sensor 25 is signal-processed in a controller 30 provided in the sensor arrangement 1 for detecting particles, and the controller is configured to determine a concentration (µg / m 3) of particulate matter contained in the air flowing into the air flow passage 11a using the processed signal, and outputs the determined value via the connector 17. Meanwhile, although the signal processing and determination may be performed in the particulate matter detection sensor assembly 1 to output the concentration of particulate matter from the particulate matter detection sensor assembly 1 as described above, the particulate matter detection sensor assembly 1 may output the signal of the light receiving sensor 25 as it is, and then the controller 30 in a device to which the particulate matter detection sensor assembly 1 is attached may perform signal processing and calculation to obtain a concentration of the particulate matter.

[0058] Fig.10 illustrates an example in which the particulate matter detection sensor assembly 1 according to an exemplary embodiment of the present invention is mounted on a vehicle to detect particulate matter contained in the air supplied to the interior of the vehicle.

[0059] An air vent 42 for supplying air into the vehicle is arranged in a crash pad 41 located in front of the vehicle interior. By attaching the sensor assembly 1 for detecting particles according to an exemplary embodiment of the present invention to a rear side of the air vent 42, the concentration of particles contained in the air supplied to the vehicle interior is measured.

[0060] An air inlet port 42a through which air enters the particulate matter sensor assembly 1 is formed in the air outlet 42, and the particulate matter sensor assembly 1 is arranged to allow the air inlet port 42a and the inlet portion 12a to communicate with each other. At this time, the contact pad 13 is located between the air inlet port 42a and the inlet portion 12a, preventing air leakage or air inlet through a region where the air inlet port 42a and the inlet portion 12a communicate with each other.

[0061] Subsequently, the particle detection sensor assembly 1 is attached to the air vent 42 by means of a fastening element, e.g., a fastening bolt 43. After passing through a mounting hole 11b, the fastening bolt 43 is screw-coupled to a mounting portion 42b, and thus the particle detection sensor assembly 1 can be attached to the inside of the air vent 42 in the vehicle.

[0062] When the particle detection sensor assembly 1 is attached to the air vent 42 as described, it is possible to measure the concentration of particles contained in the air supplied to the vehicle interior whenever necessary.

[0063] When the concentration of particulate matter in the vehicle interior is higher than a reference value after measuring the concentration of particulate matter, outside air is prevented from flowing into the vehicle, and an air purifier provided in the vehicle interior is operated, and thus it is possible to control the air quality in the vehicle interior.

[0064] According to the particulate matter sensor assembly of the present invention having the above-described configuration, dust with a relatively large particle diameter among the dust flowing into the assembly cannot enter the interior, thereby reducing dust contamination of the interior. By optimizing the air flow, movement of dust entering the light path along with air is blocked as much as possible, thus reducing a phenomenon in which the light source or the light receiving sensor is contaminated with dust. Furthermore, even if some of the dust is moved toward the light source by the dust collecting section, the light source can be prevented from being contaminated.

[0065] As described above, by reducing the contamination of the light source and the light receiving sensor as described above, the inconvenience of regularly cleaning the inside of the sensor assembly for detecting particles is eliminated, which can reduce the time and cost of cleaning the inside.

[0066] On the other hand, it is possible to increase the accuracy of the light receiving sensor by allowing light that does not fall on the light receiving sensor to be canceled out from light emitted by the light source.

[0067] For ease of explanation and precise definition in the appended claims, the terms "upper", "lower", "inner", "outer", "top", "bottom", "upper", "lower", "upward", "downward", "front", "rear", "backward", "inside", "outside", "inward", "outside", "inside", "outside", "forward" and "backward" are used to describe features of the exemplary embodiments with reference to the positions of those features as shown in the figures.

[0068] The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teachings. The exemplary embodiments were chosen and described in order to explain certain principles of the present invention and their practical application in order to enable others skilled in the art to make and utilize various exemplary embodiments of the present invention as well as various alternatives and modifications thereof. The scope of the present invention is intended to be defined by the appended claims and their equivalents.

Claims

[1] Sensor arrangement (1) for detecting particles, comprising: a housing (11) having an air flow channel (11a) through which air flows from the outside of the housing (11) into the housing; a fan drive (15) which is mounted inside the housing (11) and is arranged to flow the air from the outside of the housing (11) into the air flow channel (11a); a light source (21) arranged to emit light to allow the light to intersect with the air flowing into the air flow channel (11a); and a light receiving sensor (25) arranged to receive light scattered by dust contained in the air flowing through the air flow channel (11a), wherein the air flow channel (11a) is designed such that a region in which the air flows into the housing (11) from the outside thereof has a cross-sectional area which is larger than the cross-sectional area of ​​a region in which the light emitted by the light source (21) intersects with flowing air, wherein the housing (11) further comprises: a light path section (22) communicating with the air flow channel (11a) for radiating the light emitted by the light source (21) to the air flow channel (11a), wherein a dust collecting section (23) is formed on the light path section (22), and the dust collecting section (23) is a space formed in a direction perpendicular to the light path section (22), wherein dust collecting sections (23) are provided in multiples to form a plurality of dust collecting sections (23), and wherein the plurality of dust collecting sections (23) are formed at predetermined intervals along the light path section (22), and wherein the plurality of dust collecting sections (23) are shaped so that the cross-sectional area of ​​each of the plurality of dust collecting sections (23) becomes smaller, as the distance between the light source (21) and each of the plurality of dust collecting sections (23) increases. [2] Sensor arrangement (1) for detecting particles according to claim 1, wherein the air flow channel (11a) comprises: an inlet portion (11aa) into which the air flows from the outside of the housing (11), the inlet portion (11aa) having a predetermined cross-sectional area over a predetermined length; and a detection section (11ab) connected to the inlet section (11aa) and has a cross-sectional area which is smaller than the predetermined cross-sectional area of ​​the inlet section (11aa) and intersects with the light emitted by the light source (21). [3] The particle detection sensor assembly (1) according to claim 2, wherein the detection portion (11ab) is formed to have a cross-sectional area that is reduced and then increased in the flow direction of the air. [4] Sensor arrangement (1) for detecting particles according to claim 1, wherein the air flow channel (11a) has a minimum cross-sectional area in a region in which the air flow channel (11a) communicates with the light path section (22). [5] A particle detection sensor assembly (1) according to claim 1, wherein a light extinguishing portion (24) is formed coaxially with the light path portion (22) to allow light to pass through the air flow channel (11a) and impinge on the light extinguishing portion (24) to be extinguished in the light extinguishing portion (24). [6] Sensor arrangement (1) for detecting particles according to claim 5, wherein the light extinguishing section (24) comprises: a reflecting surface (24a) configured to reflect light passed through the air flow channel (11a) into the light extinguishing section (24); and a plurality of inclined surfaces (24b) formed at intervals such that the light reflected on the reflecting surface (24a) is extinguished after the light reflected on the reflecting surface (24a) is scattered onto the plurality of inclined surfaces (24b). [7] Sensor arrangement (1) for detecting particles according to claim 1, wherein the light receiving sensor (25) is mounted in a direction perpendicular to the light path section (22).

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