WO2018010413A1

WO2018010413A1 - Particulate matter separation and measurement apparatus

Info

Publication number: WO2018010413A1
Application number: PCT/CN2017/071678
Authority: WO
Inventors: 朱慧珑
Original assignee: 南京环康电子科技有限公司
Priority date: 2016-07-12
Filing date: 2017-01-19
Publication date: 2018-01-18
Also published as: CN106168570B; CN106168570A

Abstract

Disclosed is a particulate matter separation and measurement apparatus, the particulate matter separation apparatus comprising: a first storage chamber (201) for collecting first particulate matter; a second storage chamber (202) for collecting second particulate matter, the average particle size of the second particulate matter being smaller than the average particle size of the first particulate matter; a diversion chamber (203); a first gas flow channel (301) for connecting the diversion chamber (203) with the external space; a second gas flow channel (302) for connecting the diversion chamber (203) with the first storage chamber (201); and a third gas flow channel (303) for connecting the diversion chamber (203) with the second storage chamber (202), wherein the volume of the first storage chamber (201) and the second storage chamber (202) can be compressed and/or expanded so as to produce the gas flow, and the gas flow of the second gas flow channel (302) is less than the gas flow of the third gas flow channel (303) at least within a predetermined time period. According to the present invention, the volume and/or weight of the particulate matter separation and measurement apparatus can be reduced, and the resolution and measurement precision for the small particulate matter can be improved.

Description

Particulate matter separation and measuring device

The present application claims priority to Chinese Patent Application Serial No. No. No. No. No. No. No. No. No. No. No. No. No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No

Technical field

The present invention relates to the field of environmental gas monitoring, and in particular to a particulate matter separation and measuring device.

Background technique

As many air pollutions intensify, more and more urban residents are beginning to care about the air quality that is closely related to their health. The quality of indoor and outdoor environmental gases is directly related to people's quality of life. For example, particulate matter in the air can make people feel uncomfortable and directly or indirectly endanger people's health.

For respirable particulate matter, the particle size is different and the depth of access to the human respiratory system varies. Most of the larger particles are trapped in the upper respiratory tract, while smaller particles can enter the bronchi and even the alveoli. Therefore, particulate matter can be classified by diameter. A particle size of less than 100 microns is called TSP (Total Suspended Particle), that is, total suspended particles. A particle size of less than 10 microns, called PM10 (PM is abbreviated as Particulate Matter), can inhale particulate matter. A particle size less than 2.5 microns, called PM2.5, can enter the lung particles.

PM2.5 can also be called "fine particles", and its chemical components mainly include organic carbon (OC), elemental carbon (EC), nitrate, sulfate, ammonium salt, sodium salt (Na+) and the like. Although PM2.5 is only a small component of the ambient atmospheric composition, it has an important influence on air quality and visibility. PM2.5 has small particle size, large area, strong activity, easy to attach toxic and harmful substances (such as heavy metals, microorganisms, etc.), and has a long residence time in the atmosphere and a long transport distance, thus the human health and the quality of the atmospheric environment. The impact is even greater.

Particle measurement devices can be used in the field of ambient atmospheric monitoring to provide information on the concentration of particulate matter in the ambient atmosphere. In order to further obtain the concentration information of the respirable particulate matter in the ambient atmosphere, the particulate matter measuring device includes an air sampling device and a particulate matter detecting device. The air sampling device usually includes an air pump, an electric fan, etc., so that sufficient gas to be measured enters the particulate matter measuring device. The air sampling device can also separately separate the particles of the specified particle size from the gas for detection, and provide the concentration information of the particles of a specific particle size.

Due to the use of equipment such as air pumps, existing particulate matter measuring devices are not only expensive, but also bulky and heavy, thus causing inconvenience or even difficulty for personal and home applications.

Summary of the invention

It is an object of the present invention to provide a particulate matter separation apparatus which can reduce volume, weight and is more economical.

According to an aspect of the present invention, a particulate matter separating apparatus is provided, comprising: a first storage chamber for collecting first particulate matter; and a second storage chamber for collecting second particulate matter, the second particulate matter The average particle diameter is smaller than the average particle diameter of the first particulate matter; the splitting chamber; the first airflow passage communicating the external space with the splitting chamber; and the second airflow passage connecting the splitting chamber with the first storage chamber a third air flow passage communicating the flow dividing chamber with the second storage chamber; wherein a volume of the first storage chamber and the second storage chamber may be compressed and/or expanded to generate an air flow, And, the gas flow rate of the second gas flow passage is less than the gas flow rate of the third gas flow passage for at least a predetermined time.

Preferably, the maximum volume of the first storage chamber is smaller than the maximum volume of the second storage chamber.

Preferably, the maximum volume of the first storage chamber is 5% to 30% of the maximum volume of the second storage chamber.

Preferably, further comprising a first member and a second member, each of the first member and the second member having a hollow structure, and at least part of the wall surface being a telescopic structure, wherein the first portion is at least partially formed A storage chamber at least partially forming the second storage chamber in the second component.

Preferably, the first component is sleeved within the second component; the second storage compartment is at least partially formed between an outer wall of the first component and an inner wall of the second component.

Preferably, further comprising a third component, at least a portion of the third component being fixedly coupled to the first component, the shunting chamber being formed in the third component; the first component being provided with the first port And a second port and a third port; the diverting chamber is in communication with the first storage chamber via the second port, and the third port forms at least a portion of the third air flow passage.

Preferably, the first port is opposite to the second port, and the third port is offset from the first port.

Preferably, the first port has a predetermined distance from the second port; and further includes an adjustment structure for adjusting the predetermined distance according to the airflow speed.

Preferably, the predetermined distance is proportional to an absolute value of an average value of a velocity of movement of gas molecules flowing out of the first port at least for a predetermined time.

Preferably, the third component has a top and a bottom, the top is provided with the first port and the third port, the bottom is provided with the second port, and the adjustment structure comprises a third A resettable, retractable structure on the part.

Preferably, the adjustment structure further includes a limiting structure for limiting between the first port and the second port The distance is greater than the predetermined distance.

Preferably, the adjustment structure further includes a first adjustment rod and a second adjustment rod, one end of the first adjustment rod is connected to the bottom of the third member, and the other end is rotated with the inner wall surface of the second member Connecting, one end of the second adjusting rod is connected to the bottom of the third component, the other end is a free end, is movable and located in the third air flow passage; and further includes one end fixed to the first The inner wall surface of the two parts is connected to the elastic member of the free end of the second adjusting rod at the other end.

Preferably, the adjustment structure further includes a first adjustment rod and a second adjustment rod, one end of the first adjustment rod is connected to the bottom of the third component, and the other end is connected to the inner wall surface of the second component, the first An adjustment rod is at least partially an elastic rod, and one end of the second adjustment rod is coupled to the bottom of the third member, and the other end is movable and located in the third air flow passage.

Preferably, the top of the first component is fixedly disposed such that the relative position between the top of the first component and the first port remains unchanged.

Preferably, at least a portion of the first component is fixedly coupled to the second component via a fixed plate.

Preferably, the predetermined distance is proportional to an absolute value of an average value of a velocity of movement of gas molecules flowing through the third airflow for at least a predetermined time.

Preferably, a first tube is disposed in the third air flow passage, a first end of the first tube is in communication with the flow dividing chamber, and a second tube is disposed on the second adjusting rod, the first tube The second end is disposed opposite to the second tube.

Preferably, at least part of the wall surface of the first tube and/or the second tube is a telescopic structure; at least one connecting rib is disposed between the first tube and the second tube.

Preferably, the bottom portion is provided with a plurality of second ports, a central axis of the plurality of second ports is perpendicular to an extending direction of the first adjusting rod; a top portion of the third member is disposed with the plurality of The second port is opposite to the first port.

Preferably, further comprising a resetting member; when the first member and the second member are subjected to a tensile force, the telescopic structure is stretched, and after the tensile force is reduced, the stretched telescopic structure acts on the resetting member Lower contraction; or, when the first member and the second member are subjected to pressure, their telescopic structure contracts, and after the pressure is reduced, the contracted retractable structure is pulled down by the action of the second reset member Stretch.

Preferably, the method further includes: a first check valve for blocking the flow of the first storage chamber to the direction of the split chamber.

Preferably, the method further includes: a fourth air flow passage connecting the first storage chamber with the external space.

Preferably, the method further includes: a second one-way valve for blocking the flow of the external space toward the first storage chamber flow.

Preferably, the method further includes: a third one-way valve for blocking the flow of the external space to the second storage chamber.

According to another aspect of the present invention, a particulate matter measuring apparatus is provided, comprising: a first storage chamber for collecting first particulate matter; and a second storage chamber for collecting second particulate matter, the second particulate matter The average particle size is smaller than the average particle diameter of the first particulate matter; the splitting chamber; the first air flow passage communicating the external space with the splitting chamber; the second air flow passage, the dividing chamber and the first storage chamber a third air flow passage connecting the flow dividing chamber with the second storage chamber; a measuring chamber for measuring a concentration of the first particulate matter and/or the second particulate matter; The volumes of the first storage chamber and the second storage chamber may both be compressed and/or expanded to generate an air flow, and the gas flow rate of the second air flow passage is less than the third air flow passage for at least a predetermined time Gas flow.

Preferably, the measurement chamber includes a first measurement chamber and/or a second measurement chamber; the second measurement chamber measures a concentration of the second particulate matter in a gas flow flowing through the third gas flow passage or measures the a concentration of the second particulate matter in a second storage chamber; the first measurement chamber measures a concentration of the first particulate matter in a gas flow through the second gas flow passage or in the first storage chamber The concentration of the first particulate matter.

Preferably, a fourth component is further included in which the second measurement chamber is formed.

Preferably, the method further includes: a fifth air flow passage connecting the second measurement chamber with the external space.

Preferably, when the airflow of the fifth airflow passage flows from the second measurement chamber to the outer space, the airflow of the fifth airflow passage flows through the measurement area of the second measurement chamber.

Preferably, the fourth component is provided with a fourth one-way valve for blocking the airflow of the external space toward the second measuring chamber.

Preferably, the first measuring chamber and/or the second measuring chamber are provided with a light source and a photodetector, the light source and the photodetector being at an angle with each other to detect respectively by the first particulate matter and/or the second particulate matter The resulting scattered light.

Preferably, an absorption light cavity disposed opposite to the light source is further included for absorbing direct light of the light source.

The beneficial effects of the invention are:

According to the particulate matter separating apparatus of the present invention, the airflow is generated by compressing and/or expanding the volumes of the first storage chamber and the second storage chamber, and the airflow passage is designed to separate particles of different particle sizes by using at least part of the airflow. Since it is not necessary to use moving parts such as a fan and a motor in the separating device, the separation can be reduced The size and weight of the device reduce cost, save energy, reduce noise, be portable, and easily integrate with portable devices such as mobile phones.

According to the particulate matter measuring apparatus of the present invention, the airflow is generated by replacing and expanding the volumes of the first storage chamber and the second storage chamber. Since it is not necessary to use a moving member such as a fan in the measuring device, the size of the measuring device can be reduced, the cost can be reduced, energy consumption can be saved, noise can be reduced, portability can be facilitated, and integration with a portable device such as a mobile phone can be easily performed. The design of the airflow channel can separate particles of different particle sizes, so that the measuring chamber mainly collects small particles that people care about, so the resolution and measurement accuracy of the particle measuring device can be improved.

DRAWINGS

1a, 1b, 1c, 1d and 1e show an outline view of a particulate matter measuring apparatus according to a first embodiment of the present invention, an outline view of a second member removed, a sectional view of a line AA, and a schematic sectional view of an inhalation state. Schematic cross-sectional view of the exhaust state;

1f and 1g are schematic cross-sectional views and schematic cross-sectional views of a state of exhaust of a simplified inhalation state of the particulate matter measuring apparatus according to the first embodiment of the present invention;

2a, 2b, and 2c are a cross-sectional view showing an outline view of a second member, a schematic sectional view of an inhalation state, and an exhausted state of a particulate matter measuring apparatus according to a second embodiment of the present invention;

3a, 3b, and 3c are a schematic cross-sectional view showing a state of inhalation of a particulate matter measuring device according to a third embodiment of the present invention, a schematic sectional view of an exhaust state, and a cross-sectional view of a line BB;

4a, 4b, and 4c are a cross-sectional view showing an outline view of a second member, a schematic sectional view of an inhalation state, and an exhaust state of a particulate matter measuring apparatus according to a fourth embodiment of the present invention;

5a, 5b and 5c show a schematic cross-sectional view of a particulate matter measuring device, a cross-sectional view of a line CC, and a cross-sectional view of a line DD according to a fifth embodiment of the present invention;

Fig. 6 shows a schematic cross-sectional view of a particulate matter measuring device according to a sixth embodiment of the present invention.

7a and 7b are schematic cross-sectional views and schematic cross-sectional views of an exhaust state of a particulate matter measuring device according to a seventh embodiment of the present invention.

101, a first component; 102, a second component; 103, a third component; 1031, a limit bar; 1032, a shift lever; 104, a fourth component; 201, a first storage compartment; 202, a second storage compartment; , a diversion chamber; 204, a measurement chamber; 301, a first airflow passage; 302, a second airflow passage; 303, a third airflow passage; 304, a fourth airflow passage; 305, a fifth airflow passage; 401, a light source; Absorbing optical cavity; 403, photodetector; 501, first port; 502, second port; 503, third port; 504, fourth port; 505, fifth port; 506, sixth port; 507, seventh port; 508, eighth port; 601, first check valve; 602, a second check valve; 603, a third check valve; 701, a first spring; 702, a second spring; 703, a fixed plate; 704, a connecting member; 801, a first adjusting rod; 802, a second adjustment Rod; 803, first tube; 804, second tube; 805, connecting rib; 806, limiting member; 807, fastener.

detailed description

The following disclosure provides many different embodiments or examples for implementing different features of the present application. Specific embodiments of the components or arrangements are described below to simplify the invention. Of course, these are merely examples and are not intended to limit the invention.

In addition, in the specification and claims, the terms "first," "second," etc. are used to distinguish between the like elements, and do not necessarily describe the chronological order, the spatial order, the hierarchical order, or any other order. It is to be understood that the terms of the invention are to be construed as being in the context

It should be noted that the term "comprising", used in the claims, is not to be construed as limited Thus, it should be understood that the <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; Thus, the scope of the phrase "devices including devices A and B" should not be limited to devices consisting only of components A and B. This means that the relevant components of the device are A and B relative to the present invention.

References to "one embodiment" or "an embodiment" in this specification are intended to mean that the particular features, structures, or characteristics described in connection with the embodiments are included in at least one embodiment of the invention. Thus, the appearance of the phrases "in one embodiment" or "the" In addition, it will be apparent to those skilled in the art <RTI ID=0.0></RTI> that the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

Similarly, it will be appreciated that in the description of the exemplary embodiments of the present invention, the various features of the present invention are sometimes used together for the purpose of making the disclosure of the present disclosure smooth and to facilitate understanding of one or more aspects of the inventive aspects. The grouping is in a single embodiment, in the drawings, or in the description of the embodiments and the drawings. This method of disclosure, however, is not to be construed as a limitation of the invention as claimed. Rather, as the following claims reflect, inventive aspects reside in a particular Sign less. Thus, the claims following the Detailed Description are explicitly incorporated in the Detailed Description, wherein each claim is independently representative of a single embodiment of the invention.

In addition, although some embodiments described herein include some of the features included in other embodiments, but no other features are included in other embodiments, combinations of features of different embodiments are intended to fall within the scope of the invention and Different embodiments are understood by those skilled in the art. For example, in the following claims, any one of the claimed embodiments can be used in any combination.

It should be noted that the specific terms used in describing a particular feature or aspect of the invention should not be construed as a limitation that the term is re-defined to be limited to include the features of the invention or Any specific feature of the aspect. In the present application, the term "flow rate" refers to the volume of gas or the number of gas molecules flowing through a unit of time.

In the description provided herein, numerous specific details are set forth. However, it should be understood that the embodiments of the invention are practiced without these specific details. In other embodiments, well-known methods, structures, and techniques are not shown in detail in order not to obscure the understanding of the specification.

The present invention can be embodied in various forms, some of which are described below.

Referring to Figures 1a, 1b, 1c, 1d and 1e, a particulate matter measuring device according to a first embodiment of the present invention will be described. Fig. 1a shows an outline view of a particulate matter measuring device, Fig. 1b shows an outline view of a particulate matter measuring device with a second component removed, Fig. 1c shows a cross-sectional view along line AA of Fig. 1a, and Fig. 1d shows a particulate matter measuring device suction A schematic cross-sectional view of the gas state, and FIG. 1e shows a schematic cross-sectional view of the exhaust state of the particulate matter measuring device.

The particulate matter measuring device includes a first component 101, a second component 102, a third component 103, and a fourth component 104. The four components are composed of any material that can define the shape of the space, such as plastic, rubber, fiberglass, fiberglass, carbon fiber, glass, semiconductor, aluminum alloy, stainless steel, and the like.

The first member 101 and the second member 102 each have a hollow structure. For example, as shown in FIGS. 1a and 1b, the first member 101 and the second member 102 are cylindrical, and preferably, the first member 101 is sleeved on the second member. Within 102, preferably, the central axis of the first component 101 coincides with the central axis of the second component 102. A first storage chamber 201 is formed in the first member 101, and a second storage chamber 202 is formed between the outer wall of the first member 101 and the inner wall of the second member 102. In addition, at least a portion of the wall surfaces of the first member 101 and the second member 102 are disposed in a telescopic structure, thereby achieving compression and/or expansion of the volumes of the first storage chamber 201 and the second storage chamber 202, ie, the first member 101 and The telescopic structure of the second member 102 is stretched, and the volumes of the first storage chamber 201 and the second storage chamber 202 are expanded to compress the telescopic structure of the first member 101 and the second member 102, and then the first storage chamber 201 and The volume of the second storage chamber 202 is compressed, and gas is generated by compression and/or expansion of the volumes of the first storage chamber 201 and the second storage chamber 202. flow. The specific material of the retractable structure is not limited, and may be cloth, plastic, rubber, or the like.

The top of the third member 103 is fixedly coupled to the second member 102, and the split chamber 203 is formed in the third member 103. The fourth component 104 is coupled to the splitter chamber 203, and a measurement chamber 204 is formed in the fourth component 104. The first component 101, the second component 102, the third component 103, and the fourth component 104 together define a first airflow channel 301, a second airflow channel 302, and a third airflow channel 303. The first air flow passage 301 communicates the external space with the split chamber 203, the second air flow passage 302 communicates the split chamber 203 with the first storage chamber 201, and the third air flow passage 303 communicates the split chamber 203 with the second storage chamber 202. The third air flow passage 303 flows through the measurement chamber 204.

The maximum volume of the first storage chamber 201 is smaller than the maximum volume of the second storage chamber 202. Preferably, the maximum volume of the first storage chamber 201 is 5% to 30% of the maximum volume of the second storage chamber 202. When the first member 101 and the second member 102 are simultaneously stretched, the gas flow rate of the second air flow passage 302 is smaller than the gas flow rate of the third air flow passage 303, and as shown in FIG. 1d, the air flow enters from the external space via the first air flow passage 301. The diverting chamber 203, the first portion of the gas stream enters the first storage chamber 201 from the diverting chamber 203 via the second gas flow passage 302, and the second portion of the gas stream enters the second storage chamber 202 from the diverting chamber 203 via the third gas flow passage 303.

The first storage chamber 201 collects the first particulate matter in the gas, and the second storage chamber 202 collects the second particulate matter in the gas, wherein the average particle diameter of the second particulate matter is smaller than the average particle diameter of the first particulate matter, which is originally due to entering the first airflow. The particles of different particle sizes mixed together in the gas before the channel 301 will increase the velocity of the gas after entering the first gas flow channel 301, causing the relative movement of the particles and the gas to increase, and the particles may be separated due to the difference in particle size. Thereby, the separation of large particles and small particles in the air is achieved. As the second particulate passes through the measurement chamber 204, the measurement chamber 204 measures the concentration of the second particulate in the gas stream flowing therethrough.

Further, as shown in FIG. 1c, a light source 401, an absorption light cavity 402 opposite to the light source 401, and a photodetector 403 at an angle to the illumination direction of the light source 401 may be disposed in the measurement chamber 204. The light source 401 is an LED array light source with uniform energy distribution and may include light sources 401 of different colors. For small particles, an infrared source is preferred, and higher sensitivity can be obtained. The light emitted from the light source 401 is scattered by the particles in the measurement chamber 204 and reaches the photodetector 403. The absorption light cavity 402 absorbs the direct light of the light source 401 to reduce the adverse effect of the direct light on the measurement results.

In the measurement chamber 204, the higher the density of the particulate matter, the stronger the light intensity of the light emitted from the light source 401 after being scattered by the particulate matter to reach the photodetector 403. As a result, the measured value of the photodetector 403 represents the concentration in the measuring chamber 204. Since small particles are mainly captured in the measurement chamber 204, the measured values mainly indicate the concentration of small particles.

Specifically, the third component 103 is provided with a first port 501, a second port 502, and a third port 503, the first port The third port 503 is disposed opposite to the second port 502. The third port 503 is disposed offset from the second port 502. Preferably, the third port 503 is disposed above one side of the third member 103. The fourth member 504 is disposed on the first member 101 opposite to the second port 502. The fourth member 104 is provided with a fifth port 505 and a sixth port 506, and the fifth port 505 is disposed opposite to the third port 503 of the third member 103. The split chamber 203 communicates with the first storage chamber 201 via the second port 502 and the fourth port 504, and communicates with the measurement chamber 204 via the third port 503 and the fifth port 505. The measurement chamber 204 is in communication with the second storage chamber 202 via a sixth port 506. The number of the first to sixth ports is not limited, and may be set according to specific requirements. For example, the first port 501 and the second port 502 are each provided with two, and the other ports are one. The shunting of the airflow can be adjusted by setting the ratio of the diameter W of the first port 501 to the distance D between the first port 501 and the second port 502. Preferably, the diameter W of the first port 501 is smaller than the diameter of the second port 502.

In addition, a fourth air flow passage 304 and a fifth air flow passage 305 are further included. The fifth air flow passage 305 connects the measurement chamber 204 with the external space, and the fourth air flow passage 304 communicates the first storage chamber 201 with the external space. Specifically, the first member 101 is provided with a seventh port 507 communicating with the external space, and the fourth member 104 is provided with an eighth port 508 communicating with the external space.

Further, the fourth port 504 of the first component is provided with a first one-way valve 601 for blocking the airflow of the first storage chamber 201 toward the splitting chamber 203; the seventh port 507 of the first component 101 is provided with a first The two-way valve 602 is configured to block the airflow of the external space toward the first storage chamber 201; the eighth port 508 of the fourth component 104 is provided with a third one-way valve 603 for blocking the external space from the measurement chamber 204. Airflow.

Of course, it can be understood that the measurement chamber is not limited to measuring the concentration of the second particulate matter, in another embodiment, the measurement chamber includes the first measurement chamber and/or the second measurement chamber; and the third air flow passage 303 is subjected to the second measurement The chamber measures the concentration of the second particulate matter in the gas stream flowing therethrough; the second gas flow passage 302 measures the concentration of the first particulate matter in the gas stream flowing therethrough via the first measurement chamber.

The measurement process of the particulate matter measuring device is such that when the first member 101 and the second member 102 are stretched, as shown in FIG. 1d, the volumes of the first storage chamber 201 and the second storage chamber 202 are increased under the action of air pressure. The airflow is formed, the airflow enters the splitting chamber 203 through the first port 501, the first one-way valve 601 is opened, the second one-way valve 602 is closed, and the first portion of the airflow enters the first storage chamber 201 through the second port 502 and the fourth port 504. The third check valve 603 is closed, and the second portion of the airflow enters the measurement chamber 204 through the third port 503 and the fifth port 505, and then enters the second storage chamber 202 through the sixth port 506, and the measurement chamber 204 flows through Its air flow is measured. When the first member 101 and the second member 102 are compressed, as shown in FIG. 1e, the volumes of the first storage chamber 201 and the second storage chamber 202 are reduced, airflow is formed under the action of air pressure, and the first check valve 601 is closed. The second check valve 602 is opened, the gas in the first storage chamber 201 is discharged through the seventh port 507, the third check valve 603 is opened, and the gas in the second storage chamber 202 is sixth. After the mouth 506 enters the measurement chamber 204, a portion is discharged through the eighth port 508, and another portion enters the split chamber 203 through the fifth port 505 and the third port 503, and is discharged through the first port 501.

Preferably, when the airflow of the fifth airflow passage 305 flows from the measurement chamber 204 to the external space, the airflow of the fifth airflow passage first flows through the measurement region of the measurement chamber 204, that is, the light scattering region, and then is discharged through the eighth port 508. The measuring chamber 204 performs the particle concentration measurement on the airflow during both the inhalation process and the exhaust process, thereby improving the measurement accuracy.

Since it is not necessary to use moving parts such as a fan and a motor in the particulate matter measuring device of the present invention, the volume of the measuring device can be reduced, the weight can be reduced, the cost can be reduced, noise can be reduced, energy consumption can be saved, portability can be improved, reliability can be improved, and Easy to integrate with portable devices such as mobile phones. The design of the airflow channel can separate particles of different particle sizes, so that the measuring chamber mainly collects small particles that people care about, so the resolution and measurement accuracy of the particle measuring device can be improved.

Further, in order to improve the operation convenience and measurement accuracy, a reset component is also provided. When the first member 101 and the second member 102 are subjected to a tensile force, the telescopic structure is stretched, and after the tensile force is reduced, the stretched telescopic structure is contracted by the second reset member; or, the first member 101 and the second member When the member 102 is subjected to pressure, its telescopic structure contracts, and after the pressure is reduced, the contracted telescopic structure is elongated by the action of the second return member. In the present embodiment, a fixing plate 703 is fixed to the inner wall of the second member 102. The reset member is a first spring 701, and the first spring 701 is connected to the fixing plate 703 at one end and the bottom plate of the first member 101 and the second member 102 at the other end. The number of the first springs 701 is not limited, and may be one or more, and the arrangement manner is not limited. It may be sleeved on the outer circumference of the first component 101, or may be directly disposed on the first component 101 as shown in FIG. 1b. The outside. Of course, it is also possible to reset the first member 101 and the second member 102 by external force without resetting the reset member.

Of course, it can be understood that, in order to simplify the structure, as shown in FIGS. 1f and 1g, the seventh port 507, the eighth port 508, the first check valve 601, the second check valve 602, and the third one-way valve may not be provided. With the valve 603, the measurement process of the particulate matter measuring device becomes such that the process does not change when the first member 101 and the second member 102 are stretched, as shown in FIG. 1f, the first storage chamber 201 and the second storage chamber 202 are The volume is increased, and the airflow is formed under the action of the air pressure. The airflow enters the diverting chamber 203 through the first port 501, and the first portion of the airflow enters the first storage chamber 201 through the second port 502 and the fourth port 504, and the second portion of the airflow passes through The third port 503 and the fifth port 505 enter the measurement chamber 204 and then enter the second storage chamber 202 via the sixth port 506, which measures the flow of gas therethrough. When the first member 101 and the second member 102 are compressed, as shown in FIG. 1g, the volumes of the first storage chamber 201 and the second storage chamber 202 are reduced, and the gas in the first storage chamber 201 passes through the fourth port 504 and The second port 502 enters the diverting chamber 203 and is discharged through the first port 501. The gas in the second storage chamber 202 passes through the sixth port 506, the fifth port 505 and the third port. 503 enters the split chamber 203 and is discharged through the first port 501.

Preferably, when the airflow of the third airflow passage 303 flows from the second storage chamber 202 to the external space through the measurement chamber 204, the airflow of the third airflow passage 303 first flows through the measurement region of the measurement chamber 204, that is, the light scattering region, and then passes through The fifth port 505 and the third port 503 enter the diverting chamber 203 and are discharged through the first port 501. In this way, the measurement chamber 204 performs the particle concentration measurement on the airflow during both the inhalation process and the exhaust process, thereby improving the measurement accuracy.

Referring to Figures 2a, 2b and 2c, a particulate matter measuring device according to a second embodiment of the present invention will be described. Fig. 2a shows an outline view of the second member removed from the particulate matter measuring device, Fig. 2b shows a schematic sectional view of the inhalation state of the particulate matter measuring device, and Fig. 2c shows a schematic sectional view of the exhaust state of the particulate matter measuring device. In the drawings of the second embodiment and the subsequent embodiments, electronic components for optical detection in the measurement chamber, such as the light source 401, the absorption optical cavity 402, and the photodetector 403 in the measurement chamber, are not shown for the sake of brevity. It will be understood that the particulate matter measuring device of the present invention actually includes the above-described electronic components for optical detection.

The structure of the particulate matter measuring device provided in this embodiment is basically the same as that of the first embodiment, except that the particulate matter measuring device of the embodiment further includes an adjusting structure, and the adjusting structure can adjust the first port 501 and the second port according to the airflow speed. The distance D between 502 is to ensure good separation of particles of different particle sizes in the gas as the gas flow rate changes.

Specifically, the adjustment structure includes a telescopic structure disposed on the third component 103. The third member 103 has a top and a bottom, a first port 501 and a third port 503 are disposed on the top, and a second port 502 is disposed on the bottom. In the present embodiment, the top of the first member 101 is fixedly coupled to the inner wall of the second member 102 via a fixing plate 703, and the top of the third member 103 is fixedly coupled to the second member 102. At least part of the wall surface of the third member 103 is a telescopic structure, and the telescopic structure may be continuous or intermittent. The connecting portion between the third member 103 and the first portion 101 is an additional telescopic structure. The bottom of the third member 103 can move up and down relative to the fixed plate 703. The top of the first member 101 is fixedly disposed such that the relative position between the top of the first member 101 and the first port 501 remains unchanged, thereby ensuring that the adjustment of the distance D is only due to the absolute value of the average value of the velocity of movement of the gas molecules. The change is caused by the change in the relative position of the top of the first member 101 and the first port 501. Specifically, as shown in Figure 2a. The fixing plate 703 is directly attached to the first member 101 or connected by a connector 704 as shown in FIG. 2a. As such, it is ensured that the relative position between the top of the first member 101 and the first opening 501 remains unchanged when the first member 101 and the second member 102 are stretched or compressed.

The adjustment structure also includes a first adjustment lever 801 and a second adjustment lever 802. One end of the first adjusting rod 801 is connected to the bottom of the third member 103, and the other end is rotatably connected to the inner wall surface of the second member 102, for example, hinged to the inner wall surface of the second member 102. One end of the second adjustment lever 802 is connected to the bottom of the third member 103, and the other The end is in a movable free end and is located in the third air flow passage, preferably opposite the sixth port 506 of the fourth member 104.

When the first member 101 and the second member 102 are stretched, as shown in FIG. 2b, the particulate matter measuring device performs an inhalation action, and the free end of the second adjusting lever 802 is subjected to an impact from the sixth port 506, and the second The adjustment lever 802, the bottom of the third member 103, and the first adjustment lever 801 are rotated about the rotation axis thereof, for example, counterclockwise as shown, to change the distance D between the first port 501 and the second port 502, and When the absolute value of the average value of the moving velocity of the gas molecules in the gas flow in the third gas flow passage increases or decreases, the distance D also increases or decreases. When the first member 101 and the second member 102 are compressed, as shown in FIG. 2c, the particulate matter measuring device performs an exhausting operation, the second adjusting lever 802, the bottom of the third member 103, and the first adjusting lever 801 under the action of the airflow. It rotates in the opposite direction about its axis of rotation and restricts its continued rotation by the stop member 806.

In addition, an elastic member having one end fixed and the other end connected to the second adjustment rod 802 is further included. Preferably, the elastic member is a second spring 702, one end of which is connected to the fixing plate 703, and the other end is connected to the free end of the second adjusting rod 802.

In order to improve the adjustment precision, the sixth tube 506 of the fourth component 104 is provided with a first tube 803, and the second adjusting rod 802 is provided with a second tube 804, and the first tube 803 is opposite to the second tube 804. Preferably, a portion of the first tube 803 extends into the second tube 804.

Other aspects of the particulate matter measuring device according to the second embodiment are the same as those of the particulate matter measuring device according to the first embodiment.

Referring to Figures 3a, 3b and 3c, a particulate matter measuring device according to a third embodiment of the present invention will be described. Fig. 3a shows a schematic cross-sectional view of the inhalation state of the particulate matter measuring device, Fig. 3b shows a schematic sectional view of the exhaust state of the particulate matter measuring device, and Fig. 3c shows a cross-sectional view of the line BB in Fig. 3a.

The structure of the particle measuring device provided in this embodiment is basically the same as that of the second embodiment, except that at least part of the wall surface of the first tube 803 of the fourth member 104 and/or the second tube 804 of the second adjusting rod 802 is Scalable structure. For example, as shown in FIG. 3a, a part of the wall surface of the first tube 803 is a telescopic structure, and as shown in FIG. 3c, at least one connecting rib 805 is disposed between the first tube 803 and the second tube 804, so that A tube 803 can be followed by the second tube 804 to further improve accuracy.

Specifically, when the first member 101 and the second member 102 are stretched, as shown in FIG. 3a, the second tube 804 moves downward, and the first tube 803 moves downward together with the connecting rib 805. When the first member 101 and the second member 102 are compressed, as shown in Fig. 3b, the second tube 102 is moved upward, and the first tube 101 is moved upward together with the connecting rib 805.

Other aspects of the particulate matter measuring device according to the third embodiment and particulate matter measurement according to the second embodiment The device is the same.

Referring to Figures 4a, 4b and 4c, a particulate matter measuring device according to a fourth embodiment of the present invention will be described. Fig. 4a shows an outline view of the second member removed from the particulate matter measuring device, Fig. 4b shows a schematic sectional view of the inhalation state of the particulate matter measuring device, and Fig. 4c shows a schematic sectional view of the exhaust state of the particulate matter measuring device.

The structure of the particulate matter measuring device provided in this embodiment is similar to that of the second embodiment, and further includes an adjusting structure, and the adjusting structure can adjust the distance D between the first port 501 and the second port 502 according to the airflow speed to ensure the airflow speed. When changing, it has a good separation effect on particles of different particle sizes in the gas. The adjustment structure includes a telescopic structure disposed on the third member 103, and the second port 502 is disposed at the bottom of the third member 103. In the present embodiment, the top of the first member 101 is fixedly coupled to the inner wall of the second member 102 via a fixing plate 703, and the top of the third member 103 is fixedly coupled to the second member 102. At least part of the wall surface of the third member 103 is a telescopic structure, and the telescopic structure may be continuous or intermittent. The connecting portion between the third member 103 and the first portion 101 is an additional telescopic structure. The bottom of the third member 103 can be moved up and down, and it is ensured that the relative position between the top of the first member 101 and the first opening 501 remains unchanged when the first member 101 and the second member 102 are stretched. The adjustment structure also includes a first adjustment lever 801 and a second adjustment lever 802. One end of the second adjustment lever 802 is coupled to the bottom of the third member 103, and the other end is movable and disposed opposite the sixth port 506 of the fourth member 104. One end of the first adjustment lever 801 is coupled to the bottom of the third member 103, which is different from the second embodiment in that the other end of the first adjustment lever 801 is fixed to the inner wall of the second member 102, for example as shown in FIG. 4a. The first adjustment lever 801 is fixed to the inner wall of the second member 102 by a fastener 807. The first adjustment rod 801 is at least partially provided as an elastic rod.

When the first member 101 and the second member 102 are stretched, as shown in FIG. 4b, the particulate measuring device performs an inhalation action, and the free end of the second adjusting lever 802 is subjected to an impact from the sixth port 506, which is elastic. The first adjusting rod 801 is rotated downward, and drives the second adjusting rod 802 and the bottom of the third member 103 to rotate downward together to change the distance D between the first port 501 and the second port 502, and when the third When the absolute value of the average value of the moving velocity of the gas molecules in the airflow in the airflow passage increases or decreases, the distance D also increases or decreases. When the first member 101 and the second member 102 are compressed, as shown in FIG. 4c, the particulate matter measuring device performs an exhausting operation, the second adjusting lever 802, the bottom of the third member 103, and the first adjusting lever 801 under the action of the airflow. Rotate in the opposite direction and restrict it from continuing to rotate by the limit member 806.

Other aspects of the particulate matter measuring device according to the fourth embodiment are the same as those of the particulate matter measuring device according to the second embodiment.

A particulate matter measuring apparatus according to a fifth embodiment of the present invention will be described with reference to Figs. 5a, 5b and 5c. Figure 5a A schematic cross-sectional view of the particulate matter measuring device is shown, FIG. 5b shows a cross-sectional view along line CC in FIG. 5a, and FIG. 5c shows a cross-sectional view along line DD in FIG. 5a.

The structure of the particulate matter measuring device provided in this embodiment is substantially the same as that of the fourth embodiment, except that, as shown in FIG. 5b, the top portion of the third component 103 of the particulate matter measuring device of the present embodiment is provided with a plurality of first ports 501. The center line of the plurality of first ports 501 is perpendicular to the extending direction of the first adjustment rod 801. As shown in FIG. 5c, the bottom of the third member 103 is provided with a plurality of second ports 502, and the center lines of the plurality of second ports 502 are perpendicular to the extending direction of the first adjusting rod 801. The structure can ensure that the difference between the values of the distances D of the plurality of first ports 501 and the plurality of second ports 502 opposite thereto is small when rotating at the bottom of the third member 103, thereby increasing the measurement accuracy.

Other aspects of the particulate matter measuring device according to the fifth embodiment are the same as those of the particulate matter measuring device according to the fourth embodiment.

Referring to Fig. 6, a particulate matter measuring apparatus according to a sixth embodiment of the present invention will be described. Fig. 6 shows a schematic cross-sectional view of a particulate matter measuring device.

Specifically, the adjustment structure includes a resettable retractable structure disposed on the third member 103, and the second port 502 is disposed on the bottom of the third member 103. In the present embodiment, the top of the first member 101 is fixedly coupled to the inner wall of the second member 102 via a fixing plate 703, and the top of the third member 103 is fixedly coupled to the second member 102. At least a portion of the wall of the third member 103 is a resettable telescoping structure, and the retractable telescoping structure may be continuous or intermittent. The connecting portion between the third member 103 and the first portion 101 is an additional telescopic structure. The bottom of the third member 103 can be moved up and down, and it is ensured that the relative position between the top of the first member 101 and the first port 501 remains unchanged when the first member 101 and the second member 102 are stretched or compressed.

Further, the adjustment structure further includes a limiting structure for limiting the distance D between the first port 501 and the second port 502 by a predetermined distance, that is, preventing the distance between the first port 501 and the second port 502 from being too close. In a preferred embodiment, as shown in FIG. 6, the limiting structure includes a limiting rod 1031. One end of the limiting rod 1031 is connected to the inner wall of the rigid structure of the third member 103, and the other end is located at the bottom of the third member 103. At a certain distance, when exhausting, the limit rod 1031 and the bottom of the third member 103 can abut to limit the continued movement of the bottom.

When the absolute value of the average value of the moving velocity of the gas molecules in the airflow flowing from the first port 501 to the bottom increases or decreases, the distance D also increases or decreases, and when the absolute value of the moving average value of the gas molecules is about zero, the resettable of The retractable structure keeps the distance D approximately constant. Since the telescopic structure is resettable, the first adjustment lever and the second adjustment lever in Embodiments 2 to 5 are omitted, further simplifying the structure.

Referring to Figures 7a and 7b, a particulate matter measuring apparatus according to a seventh embodiment of the present invention will be described. Fig. 7a shows a schematic sectional view of the inhalation state of the particulate matter measuring device, and Fig. 7b shows a schematic sectional view of the exhaust state of the particulate matter measuring device.

The structure of the particulate matter measuring apparatus provided in this embodiment is basically the same as that of the sixth embodiment. In the present embodiment, the top of the third component 103 is fixedly coupled to the second component 102. The difference in this embodiment is that the wall surface of the third member 103 is a rigid structure. The top of the first component 101 is fixedly coupled to the inner wall of the second component 102 via a fixing plate 703 and/or the top of the first component 101 is fixedly coupled to the second component 102 via the wall surface of the third component 103. The bottom of the third member 103 is connected to the inner peripheral surface of the third member via the elastic structure or at least a portion of the structure of the bottom is elastic so that the bottom portion can move up and down. Optionally, at least a portion of the bottom of the third member 103 is made of a repositionable retractable rubber and a second port 502 is provided on the bottom to further simplify the structure.

The third member 103 is also provided with a limiting structure for restricting the distance D between the first port 501 and the second port 502 to be greater than a predetermined distance, and prevents the distance between the first port 501 and the second port 502 from being too close. In a preferred embodiment, as shown in Figures 7a and 7b, the stop structure includes a shift lever 1032 disposed on the inner peripheral wall of the third member 103. When exhausting, the bottom of the third member 103 is coupled to the shift lever 1032. Then limit the continued movement of the bottom.

When the absolute value of the average value of the moving velocity of the gas molecules in the airflow flowing from the first port 501 to the bottom increases or decreases, the distance D also increases or decreases, and when the absolute value of the moving average value of the gas molecules is about zero, The reset telescopic structure keeps the distance D approximately constant.

It is to be understood that the present invention is not limited to the above-described particulate matter measuring device. In an alternative embodiment, the measuring chamber of the above-described particulate measuring device is removed and used as a particulate matter separating device, and combined with other measuring means to achieve particle concentration. measuring.

The above-described embodiments are only examples of the invention, and although the embodiments and the drawings of the invention are disclosed for the purpose of illustration, it will be understood by those skilled in the art Various substitutions, changes, and modifications are possible. Therefore, the invention should not be limited to the details disclosed in the embodiments and the drawings.

Claims

A particle separation device, comprising:

a first storage chamber for collecting the first particulate matter;

a second storage chamber for collecting second particles, wherein the second particles have an average particle diameter smaller than an average particle diameter of the first particles;

Diversion chamber

a first air flow passage connecting the external space with the flow dividing chamber;

a second air flow passage connecting the flow dividing chamber with the first storage chamber;

a third air flow passage connecting the flow dividing chamber with the second storage chamber;

Wherein the volumes of the first storage chamber and the second storage chamber may both be compressed and/or expanded to generate a gas flow, and the gas flow rate of the second gas flow passage is less than the first time for at least a predetermined time The gas flow rate of the three air flow channels.
The particulate matter separation apparatus according to claim 1, wherein a maximum volume of said first storage chamber is smaller than a maximum volume of said second storage chamber.
The particulate matter separation device according to claim 2, wherein the maximum volume of the first storage chamber is 5% to 30% of the maximum volume of the second storage chamber.
The particulate matter separating apparatus according to claim 1, further comprising a first member and a second member, each of the first member and the second member having a hollow structure, and at least a part of the wall surface being a telescopic structure The first storage chamber is at least partially formed in the first component, and the second storage chamber is at least partially formed in the second component.
The particulate matter separation device according to claim 4, wherein the first component is sleeved within the second component;

The second storage chamber is at least partially formed between an outer wall of the first component and an inner wall of the second component.
A particulate matter separating apparatus according to claim 4, further comprising a third member, at least a portion of which is fixedly coupled to said first member, and said diverting chamber is formed in said third member ;

The first member is provided with a first port, a second port and a third port;

The diverting chamber is in communication with the first storage chamber via the second port, and the third port forms at least a portion of the third air flow passage.
The particulate matter separating apparatus according to claim 6, wherein the first port is disposed opposite to the second port, and the third port is offset from the first port.
The particulate matter separation device according to claim 6, wherein the first port and the second port have a predetermined distance;

Also included is an adjustment structure for adjusting the predetermined distance in accordance with the airflow speed.
The particulate matter separating apparatus according to claim 8, wherein said predetermined distance is proportional to an absolute value of an average value of a velocity of movement of gas molecules flowing out of said first port at least for a predetermined time.
The particulate matter separating apparatus according to claim 8, wherein said third member has a top portion and a bottom portion, said top portion is provided with said first port and said third port, and said bottom portion is provided with said second port The adjustment structure includes a resettable telescopic structure disposed on the third component.
The particulate matter separation device according to claim 10, wherein the adjustment structure further comprises a stopper structure for restricting a distance between the first port and the second port to be greater than a predetermined distance.
The particulate matter separating apparatus according to claim 10, wherein

The adjustment structure further includes a first adjustment rod and a second adjustment rod, one end of the first adjustment rod is connected to the bottom of the third component, and the other end is rotatably connected to the inner wall surface of the second component. One end of the second adjusting rod is connected to the bottom of the third component, and the other end is a free end, is movable and located in the third air flow passage;

There is further provided an elastic member having one end fixed to the inner wall surface of the second member and the other end connected to the free end of the second adjustment rod.
The particulate matter separating apparatus according to claim 10, wherein said adjustment structure further comprises a first adjustment lever and a second adjustment lever, one end of said first adjustment lever being coupled to said bottom portion of said third member The other end is connected to the inner wall surface of the second component, the first adjusting rod is at least partially an elastic rod, and one end of the second adjusting rod is connected to the bottom of the third component, and the other end is movable. The state is located in the third airflow passage.
A particle separation device according to any one of claims 10 to 13, wherein the top of the first member is fixedly disposed such that the relative between the top of the first member and the first port The location remains the same.
The particulate matter separation device according to claim 8, wherein at least a portion of the first member is fixedly coupled to the second member via a fixing plate.
The particulate matter separating apparatus according to claim 12 or 13, wherein said predetermined distance The absolute value of the average value of the velocity of movement of the gas molecules flowing through the third gas flow is at least for a predetermined time.
The particulate matter separation device according to claim 12 or 13, wherein a first tube is disposed in the third air flow passage, and a first end of the first tube is in communication with the flow dividing chamber, the second A second tube is disposed on the adjustment rod, and the second end of the first tube is disposed opposite to the second tube.
The particulate matter separation device according to claim 17, wherein at least part of the wall surface of the first tube and/or the second tube is a telescopic structure;

At least one connecting rib is disposed between the first tube and the second tube.
The particulate matter separating apparatus according to claim 12 or 13, wherein said bottom portion of said third member is provided with a plurality of second ports, a central axis of said plurality of second ports and said first adjustment The rod extends in a direction perpendicular;

The top of the third component is provided with a plurality of first ports opposite the plurality of second ports.
The particulate matter separation device according to claim 4, further comprising a reset member;

When the first member and the second member are subjected to a tensile force, the telescopic structure is stretched, and after the tensile force is reduced, the stretched telescopic structure is contracted by the reset member; or When a component and the second component are subjected to pressure, their telescopic structure contracts, and after the pressure is reduced, the contracted retractable structure is stretched by the second reset member.
The apparatus for separating particulate matter according to claim 1, further comprising:

a first one-way valve for blocking the flow of the first storage chamber to the direction of the split chamber.
The apparatus for separating particulate matter according to claim 1, further comprising:

The fourth air flow passage connects the first storage chamber with the external space.
The apparatus for separating particulate matter according to claim 1, further comprising:

a second one-way valve for blocking the flow of the external space to the direction of the first storage chamber.
The apparatus for separating particulate matter according to claim 1, further comprising:

The third check valve is configured to block the flow of the external space to the second storage chamber.
A particulate matter measuring device, comprising:

a first storage chamber for collecting the first particulate matter;

a second storage chamber for collecting second particles, wherein the second particles have an average particle diameter smaller than an average particle diameter of the first particles;

Diversion chamber

a first air flow passage connecting the external space with the flow dividing chamber;

a second air flow passage connecting the flow dividing chamber with the first storage chamber;

a third air flow passage connecting the flow dividing chamber with the second storage chamber;

a measurement chamber for measuring a concentration of the first particulate matter and/or the second particulate matter;

Wherein the volumes of the first storage chamber and the second storage chamber may both be compressed and/or expanded to generate a gas flow, and the gas flow rate of the second gas flow passage is less than the first time for at least a predetermined time The gas flow rate of the three air flow channels.
The particulate matter measuring device according to claim 25, wherein the measuring chamber comprises a first measuring chamber and/or a second measuring chamber;

The second measuring chamber measures a concentration of the second particulate matter in a gas stream flowing through the third gas flow passage or a concentration of the second particulate matter in the second storage chamber;

The first measurement chamber measures a concentration of the first particulate matter in a gas stream flowing through the second gas flow passage or a concentration of the first particulate matter in the first storage chamber.
The particulate matter measuring device according to claim 26, further comprising a fourth member in which said second measuring chamber is formed.
The particulate matter measuring apparatus according to claim 26, further comprising: a fifth air flow passage that communicates the second measurement chamber with the external space.
The particulate matter measuring device according to claim 28, wherein when the airflow of the fifth airflow passage flows from the second measuring chamber to the outer space, the airflow of the fifth airflow passage flows through The measurement area of the second measurement chamber.
The particulate matter measuring device according to claim 28, wherein said fourth member is provided with a fourth one-way valve for blocking the flow of the external space toward said second measuring chamber.
The particulate matter measuring device according to claim 26, wherein the first measuring chamber and/or the second measuring chamber are provided with a light source and a photodetector, the light source and the photodetector being at an angle to each other The scattered light generated by the first particulate matter and/or the second particulate matter, respectively, is detected.
The particulate matter measuring device according to claim 31, further comprising an absorbing optical cavity disposed opposite said light source for absorbing direct light of said light source.