PARTICLE COLLECTION CONTAINER, PARTICLE COLLECTION DEVICE, AND PARTICLE COLLECTION METHOD

Abstract

To improve charging performance and trapping performance, and facilitate a subsequent process after particle trapping.SOLUTION: A particle trapping container 2 for charging and trapping particles in the air includes: a container body 7 having an opening 8; a suction port 14 that is provided in the opening 8 and has an inflow path 22 that flows the air to the inside from the outside of the container body 7; a discharge part 16 that is provided in the opening 8 and has an outflow path 26 that flows the air to the outside from the inside of the container body 7; an electrode 15 for discharge that is provided inside the container body 7 and is applied with a high voltage; and a medium storage part 50 that is provided inside the container body 7, and can store the medium trapping the particles in the air charged by the electrode 15 for discharge.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a particle collection container that electrically charges and collects particles in the air, a particle collection device that includes the particle collection container, and a particle collection method that collects particles in the air. [Background technology]

[0002] Conventionally, collection devices have been used to investigate the state of contamination by airborne microorganisms in pharmaceutical factories, food factories, hospitals, living spaces, etc. For example, Patent Document 1 proposes a technology in which a discharge electrode and a collection electrode are provided in a collection container, and suspended particulate matter collected in the collection container is attached onto a transparent flat collection electrode. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2003-214997 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the technique described in Patent Document 1 above has the following problems.

[0005] (1) In Patent Document 1, the collection vessel has three openings: an opening at the top, an inlet on the side through which air flows in, and a communication port corresponding to an outlet. Therefore, in order to safely store and transport the particles after collection, it is necessary to take the time to seal all of the openings. In addition, such collection vessels are not available on the market, and it is necessary to machine a commercially available product or to manufacture a new one, which increases costs.

[0006] (2) Because the dust collection electrode is not disposed over the entire bottom of the collection container, there is a risk that fine particles will accumulate and adhere to the bottom, making it difficult to improve collection performance. In addition, with the arrangement of the inlet, discharge electrode, and communication port as shown in Patent Document 1, there is a risk that the charged particles will not be collected by the dust collection electrode and will flow directly into the communication port (discharge port), making it difficult to improve collection performance. Furthermore, because the inlet is disposed on the side of the collection container, fine particles in the air introduced into the collection container do not necessarily pass through the charged area generated by the discharge electrode, making it difficult to improve charging performance.

[0007] (3) The collected fine particles are collected on a transparent flat plate (a collection electrode having a conductive transparent film formed on the surface of the transparent plate). Therefore, when the particles collected on the flat plate are to be used in a later process such as PCR processing, a process of scraping the particles off the flat plate is required, which is time-consuming.

[0008] The present invention has been made to solve the above-mentioned problems, and has an object to provide a particle collection container, a particle collection device, and a particle collection method that are economical, allow the next step after particle collection to be easily carried out, and can improve charging performance and collection performance. [Means for solving the problem]

[0009] In order to achieve the above-mentioned object, a first particle collection container of the present invention is a particle collection container that charges and collects particles in the air, and is characterized in that it comprises a container body having an opening, an inlet section provided at the opening and having an inlet passage for introducing air from the outside of the container body to the inside, an outlet section provided at the opening and having an outlet passage for introducing air from the inside of the container body to the outside, a discharge electrode provided inside the container body and to which a high voltage is applied, and a medium containing section provided inside the container body and capable of containing a medium for collecting particles in the air that have been charged by the discharge electrode. In the second particle collecting container of the present invention, the medium is a conductive liquid.

[0010] According to the first and second particle collection containers of the present invention, since the opening of the container body is provided with a suction part and a discharge part, containers available on the market can be used as they are without processing, which improves economy. In addition, since the particles are collected in the medium inside the container body, the process after particle collection (collection) (e.g., PCR processing) can be easily performed, and handling can be easily performed.

[0011] In a third particle collection container of the present invention, the suction section has a conductive cylindrical body having one end open to the outside of the container body and the other end open to the inside of the container body, and the discharge electrode is provided at the other end of the cylindrical body facing the liquid.

[0012] According to the third particle collection container of the present invention, the air sucked into the container body is guided close to the liquid surface and collided with the liquid surface, thereby making it possible to bring the particles in the air into contact with and mix them with the liquid, thereby improving the particle collection efficiency. Also, since the discharge electrode is provided on the conductive cylinder, the mechanism for power supply (application of high voltage) can be simplified.

[0013] In a fourth particle collection container of the present invention, the opening area of ​​the other end side of the suction part is set smaller than the opening area of ​​the one end side of the suction part.

[0014] According to the fourth particle collection container of the present invention, the speed at which the air flowing inside from the suction part collides with the liquid surface increases, so that the degree to which the particles come into contact with and are mixed with the liquid increases, thereby improving the particle collection efficiency.

[0015] In a fifth particle collecting container of the present invention, the discharge electrode is configured as a wire electrode having a bundle portion formed by bundling fibers.

[0016] According to the fifth particle collection container of the present invention, the wire electrode can generate a charged area at a lower voltage than the needle electrode, and therefore, for example, it can be operated by a battery that has excellent portability. Also, since the discharge electrode is composed of a wire electrode having a bundled part of bundled fibers, dirt is less likely to adhere to the electrode, and even if, for example, the discharging wire electrode becomes unable to discharge due to dirt, another wire electrode starts discharging due to alternating current, so that excellent durability can be realized.

[0017] In a sixth particle collection container of the present invention, the discharge electrodes are arranged at equal intervals along a circumferential direction of the suction portion, and a tip of each discharge electrode is provided protruding from the suction portion toward the liquid surface side of the liquid and is arranged at a position spaced a certain distance from the liquid surface.

[0018] According to the sixth particle collection container of the present invention, the tip of the discharge electrode protrudes toward the liquid surface side beyond the suction part, so that the suction part does not affect the charged area generated by the discharge electrode, and particles in the air flowing in from the suction part can be reliably charged.

[0019] A seventh particle collection container of the present invention is characterized in that it comprises a grounding portion extending from an opening of the container body toward the inside and in contact with the liquid, and the outer periphery of the grounding portion is covered with a non-conductive member.

[0020] According to the seventh particle collection container of the present invention, the grounding part is in contact with the liquid in the container body by utilizing the opening of the container body, so that additional processing of the container body is not required and the liquid can be easily grounded. In addition, by protecting the outer periphery of the grounding part with a non-conductive member, it is possible to prevent the charged particles from adhering to the grounding part.

[0021] In an eighth particle collecting container of the present invention, a conductive biasing member is provided at an end of the grounding portion on the liquid side.

[0022] According to the eighth particle collection container of the present invention, even if there is variation in the distance from the opening of the container body to the liquid level due to variations in the installation condition of the grounding portion or the amount of liquid stored, the variation in the distance from the opening of the container body to the liquid level can be absorbed by the biasing member, so that the liquid can be reliably grounded.

[0023] In a ninth particle collection container of the present invention, a repulsion portion is provided in the suction portion, and the repulsion portion is provided along the liquid surface at a position spaced a certain distance from the liquid surface.

[0024] According to the ninth particle collection container of the present invention, the charged particles in the air flow so as to diffuse around the liquid surface, so that the entire liquid surface can be effectively utilized and the particle collection efficiency can be improved. Also, by forming a flow passage between the repulsion part and the liquid surface, the internal space of the container can be effectively utilized.

[0025] In the tenth particle collection container of the present invention, the repulsion portion has a planar shape similar to and smaller than the opening of the container body, and is supported at the other end of the suction portion and at the grounding portion via an insulating member.

[0026] According to the tenth particle collection container of the present invention, the repulsion part can be easily housed in the container body. Moreover, since the repulsion part is supported by the other end of the suction part and the grounding part, the repulsion part can be easily attached, and the members housed in the container body can be unitized, so that the attachment and detachment work to the container body can be easily performed.

[0027] In an eleventh particle collection vessel of the present invention, the main component of the liquid is water, the liquid is formed as a liquid film having a thickness of 1 mm or less, and contains a surfactant.

[0028] According to the eleventh particle collection container of the present invention, by keeping the amount of liquid small, it is possible to prevent a decrease in the concentration of the specimen in the next process (e.g., PCR processing, etc.). In addition, by mixing a surfactant into the liquid, viruses collected in the liquid can be inactivated, and the container can be safely transferred to the next process.

[0029] In the twelfth particle collection vessel of the present invention, the liquid contains an antioxidant.

[0030] According to the twelfth particle collection container of the present invention, damage to genes caused by oxidative radicals generated by discharge can be reduced, and the accuracy of analysis after particle sampling can be improved.

[0031] In a thirteenth particle collection vessel of the present invention, the liquid contains a salt having deliquescent properties.

[0032] According to the 13th particle collection container of the present invention, moisture in the air can be absorbed and evaporation of the liquid can be suppressed, so that the inner surface of the container body can be kept wet and the particle collection effect can be maintained at a high level.

[0033] In the fourteenth particle collection container of the present invention, the opening of the container body is formed in an upper part opposite to the bottom of the container body, the bottom is formed flat, and the inner surface of the container body is water-repellent.

[0034] According to the 14th particle collection container of the present invention, containers with an open top are a common shape on the market, so the container body is easy to obtain and is economical. In addition, since the bottom of the container body is flat, a liquid layer with a uniform liquid level can be formed. Therefore, the discharge performance can be stably maintained. In addition, since the inner surface of the container body is water repellent, the collected particles are less likely to adhere (adsorb) to the inner surface of the container and are reliably collected in the liquid, so that the collection efficiency can be improved.

[0035] In the fifteenth particle collecting container of the present invention, the container body is a vial.

[0036] According to the fifteenth particle collection container of the present invention, the container body can be sealed, so that the particles can be safely stored and transported after collection. In addition, vials are containers used in the medical and pharmaceutical fields, specimen collection, etc., and are highly distributable (marketable) and can be obtained relatively inexpensively. Furthermore, the inner surface of the vial is water repellent, so that collected particles are unlikely to adhere (be adsorbed) to the vial, and are reliably collected in the liquid, improving collection efficiency.

[0037] The sixteenth particle collection container of the present invention is characterized in that it comprises an electrode unit provided with the suction portion having the discharge electrode and a power supply contact portion, the discharge portion, and a grounding portion in contact with the liquid, and the electrode unit is detachably provided at an opening of the container body.

[0038] According to the sixteenth particle collection container of the present invention, since the multiple parts housed in the container body are unitized, by supplying liquid into the container body and then attaching the electrode unit to the opening, the container body is ready for collection (collection), improving usability. Also, by removing the electrode unit from the container body, the upper part of the liquid is open, making it easy to handle the liquid.

[0039] In the seventeenth particle collection container of the present invention, the upper surface of the electrode unit is formed flat, and the suction portion, the discharge portion and the grounding portion do not protrude from the upper surface of the electrode unit.

[0040] According to the seventeenth particle collection container of the present invention, the lid can be securely attached, so that the airtightness (sealing ability) of the inside of the container body can be guaranteed.

[0041] A first particle collection device of the present invention is a particle collection device including the above-mentioned particle collection container, and further includes a power supply unit detachable from the particle collection container, the power supply unit including an intake flow path capable of communicating with the inlet path of the suction portion, an exhaust flow path capable of communicating with the outlet path of the exhaust portion, a power supply member capable of contacting a power supply contact portion formed on the suction portion, and a grounding member capable of contacting a grounding portion that contacts the medium.

[0042] According to the first particle collection device of the present invention, the suction flow path, the exhaust flow path, the power supply member, and the grounding member are integrated into the power supply unit. Therefore, by setting the particle collection container in the particle collection device and attaching the power supply unit to the container body, the charging and collection of particles in the air can be easily performed.

[0043] The second particle collection device of the present invention is characterized in that it comprises an on-off valve provided in a flow passage upstream of the suction flow passage of the power supply unit, and suction means provided in a flow passage downstream of the exhaust flow passage of the power supply unit, and during operation, the suction means operates continuously, and the on-off valve is controlled to alternately perform opening and closing operations.

[0044] According to the second particle collection device of the present invention, when the on-off valve is closed while the suction means is continuously suctioning, the pressure inside the container is increased, and when the on-off valve is then switched to an open operation, the speed at which the air containing particles is sucked in from the suction port moves toward the liquid surface increases and the air collides with the liquid surface with great force, improving the degree to which the particles come into contact with and are mixed with the medium and increasing the efficiency of collection of particles in the air.

[0045] A third particle collecting device of the present invention is characterized in that, during operation, the on-off valve is controlled so that the time during which it is in an open state is longer than the time during which it is in a closed state.

[0046] According to the third particle collection device of the present invention, the time in the open state is controlled to be longer than the time in the closed state, thereby making it possible to improve collection efficiency while keeping the effect of the degree of particle collection per unit time low.

[0047] A first particle collection method of the present invention is a particle collection method for collecting particles in the air using the above-mentioned particle collection device, and is characterized by including a medium supplying step of supplying the medium into the container body, an air suction step of sucking air containing particles into the container body after the medium supplying step, a particle charging step of charging the particles in the air sucked in in the air suction step by applying a high voltage to the discharge electrode, and a particle collection step of collecting the particles charged in the particle charging step by the medium supplied into the container body in the medium supplying step.

[0048] According to the first particle collection method of the present invention, particles in the air are always charged, then sucked into the container and mixed with the medium stored at the bottom before being collected, so that the medium can be used effectively. In addition, since the particles in the air are collected in the medium in the container, each process (e.g., PCR process, etc.) in the next step after the particle collection can be easily performed.

[0049] In the second particle collection method of the present invention, the particles include microorganisms, bacteria, or viruses.

[0050] According to the second particle collection method of the present invention, microorganisms, bacteria, and viruses can be efficiently collected. Effect of the Invention

[0051] According to the present invention, various excellent effects can be obtained, such as excellent cost efficiency, easy processing in the next step after particle collection, and improved charging performance and collection performance. [Brief description of the drawings]

[0052] [Figure 1] 1 is an exploded perspective view showing a particle collection container according to an embodiment of the present invention, viewed obliquely from above. [Diagram 2] 1 is a perspective view showing a particle collecting device according to an embodiment of the present invention, viewed obliquely from above. [Diagram 3]3 is a cross-sectional view taken along the line Z1-Z1 in FIG. 2. [Figure 4A] FIG. 2 is a perspective view showing a power supply unit of the particle collecting device according to the embodiment of the present invention, viewed obliquely from above. [Figure 4B] This is a cross-sectional view taken along the line Z2-Z2 of FIG. 4A. [Figure 4C] FIG. 2 is a perspective view showing a power supply unit of the particle collecting device according to the embodiment of the present invention, viewed obliquely from below. [Diagram 5] FIG. 11 is a perspective view showing another type of particle collection container according to an embodiment of the present invention, viewed obliquely from above. [Figure 6] FIG. 11 is an exploded perspective view showing a state in which an electrode unit is removed from another type of particle collection container according to an embodiment of the present invention, viewed obliquely from above. [Figure 7] FIG. 2 is a cross-sectional view showing another type of particle collection device according to an embodiment of the present invention. [Figure 8] XX cross-sectional view of FIG. 7. [Figure 9] FIG. 13 is a perspective view showing a modified example of the suction portion of the particle collection container according to the embodiment of the present invention. [Figure 10] 1 is a block diagram showing a configuration of a particle collecting device according to an embodiment of the present invention. [Figure 11] 5 is a time chart showing the operation of the particle collecting device according to the embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0053] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. In the following description, the terms "upstream" and "downstream" and similar terms refer to "upstream" and "downstream" in the air flow direction and similar concepts.

[0054] [Particle collection device] First, a particle collecting device according to an embodiment of the present invention will be described with reference to FIGS. 1 to 4C. Here, FIG. 1 is an exploded perspective view showing a particle collection container according to an embodiment of the present invention from diagonally above. FIG. 2 is a perspective view showing a particle collecting device according to an embodiment of the present invention from diagonally above, and FIG. 4A is a cross-sectional view taken along the line Z1-Z1 of FIG. 4A, and FIG. 4B is a perspective view of a power supply unit of a particle collecting device according to an embodiment of the present invention. 4B is a cross-sectional view taken along the line Z2-Z2 of FIG. 4A; and FIG. 4C is an embodiment of the present invention. 1 is a perspective view showing a power supply unit of a particle collecting device according to the embodiment of the present invention, viewed obliquely from below.

[0055] The particle collecting device 1 according to this embodiment is a device for charging and collecting particles in the air, and the particles in the air that are to be collected by the particle collecting device 1 include, in addition to dust, bioparticles such as microorganisms, bacteria, and viruses. The particle collecting device 1 is configured to include a particle collecting container 2 that is detachably provided to the particle collecting device 1, a power supply unit 3 that is detachably attached to the particle collecting container 2, a suction device 4 that introduces air into the particle collecting container 2, a discharge device 5 that causes air to flow out from the particle collecting container 2, and a control device 6 (see FIG. 10) that controls the particle collecting device 1.

[0056] <Particle collection vessel> The particle collection container 2 includes a container body 7 having a cylindrical shape with a bottom and a tapered top. An opening 8 is formed at the upper end of the container body 7, and the container body 7 has a structure that allows this opening 8 to be sealed (hermetically closed) with a lid 9. By making the container body 7 have such a sealable (hermetically closed) structure, storage and transportation after bioparticle collection can be performed safely.

[0057] The container body 7 is preferably a glass vial, but may be made of plastic. The inner surface of the container body 7 may be water-repellent coated (for example, silicon coated or Teflon (registered trademark) coated). When the container body 7 is a vial, a rubber stopper is inserted into the opening 8, so that it is highly airtight and there is little risk of contamination (mixing in foreign matter). In addition, since it is made of glass, the items stored in the container body 7 are hardly affected by chemical deterioration originating from the container body 7, so that it can be stably stored for a long period of time. Furthermore, vials are used in a wide range of places such as research facilities and analysis institutions, and are highly distributed. In addition, since glass, which is the raw material, is water-repellent, adhesion of the captured viruses to the inner surface of the container body 7 can be minimized even if the inner surface of the container body 7 is not water-repellent coated.

[0058] The bottom 10 of the container body 7 preferably has a flat shape, and the container body 7 is provided with a medium storage section 50 capable of storing the medium in a film form on the bottom 10. The bottom 10 of the container body 7 does not necessarily have to have a flat shape, and may have a non-flat shape with a raised center, in which case the film may be formed thicker.

[0059] The medium is a conductive liquid 11, which may be in a gel, jelly, or powder form. The main component of the liquid 11 is water (e.g., pure water, sterilized water, distilled water), and the substances mixed with the liquid 11 include a surfactant (e.g., AVL buffer), an antioxidant (e.g., glucose), salt, an antioxidant (e.g., vitamin C), glucose, and an evaporation prevention agent (e.g., glycerin).

[0060] The concentration of the surfactant is set to a few percent, specifically about 5%. The surfactant can lower the surface tension and improve wettability so that the liquid can spread easily on the glass surface. By mixing the surfactant with water, the virus can be rendered harmless (detoxified).

[0061] Furthermore, by mixing an antioxidant into the water, it is possible to reduce damage to genes caused by oxidative radicals generated by discharge, thereby improving the accuracy of analysis after particle sampling.

[0062] The salt concentration is set to a few percent, specifically, about 2%. By mixing deliquescent salt with water, moisture in the air can be absorbed and evaporation of the liquid can be suppressed, so that the inner surface of the container body 7 can be kept wet, and the particle collection effect can be maintained at a high level.

[0063] In addition, mixing antioxidants (vitamin C) and glucose into the water can reduce DNA stress and prevent damage, and mixing an evaporation prevention material into the water can prevent the liquid from evaporating.

[0064] The liquid 11 is supplied to the medium storage section 50 so as to form a liquid film having a thickness of 2 mm or less, preferably 1 mm or less. A liquid film is sufficient to collect bioparticles from the air, and by keeping the amount of liquid collected small, it is possible to prevent a decrease in the concentration of the specimen in the next process (e.g., PCR processing). Furthermore, by using a liquid film, there is no risk of the liquid 11 leaking out even if the particle collection container 2 is slightly tilted. Furthermore, it is not necessary to mix an enzyme (reagent) for identifying microorganisms in advance with the liquid film. This is because it is preferable to add the enzyme before the process after collection (e.g., PCR processing) since the enzyme is not weakened.

[0065] An electrode unit 12 is detachably provided at the opening 8 of the container body 7. The electrode unit 12 is configured to include a support 13, an inlet portion 14, a discharge electrode 15, an outlet portion 16, and a ground portion 17.

[0066] The support 13 is made of a non-conductive material, and may be formed, for example, by processing a rubber stopper. The support 13 is composed of a cylindrical body 18 that is detachable from the opening 8 of the container body 7, and a flat cylindrical flange 19 formed above the body 18. The flange 19 acts as a stopper to prevent the support 13 from falling into the container body 7. The upper surface of the support 13 has a flat shape, and this allows the lid 9 to be securely closed to seal the container body 7 after particle sampling is completed, thereby preventing particles from scattering outside the container body 7.

[0067] The suction section 14 has a cylindrical body 20 in a vertically elongated cylindrical shape. The cylindrical body 20 may have a cylindrical shape other than a cylindrical shape, such as a polygonal cylindrical shape. The cylindrical body 20 penetrates the support body 13 in the vertical direction, and an upper part 21 is supported by the support body 13. The upper end of the cylindrical body 20 is open to the outside of the container body 7, and an inflow passage 22 is formed inside the cylindrical body 20. A plate-shaped power supply contact part 23 is formed to protrude from one peripheral edge part of the upper end of the cylindrical body 20 so as to follow the upper surface of the support body 13 (see FIG. 1). The cylindrical body 20 is supported by the support body 13 in a state in which its upper end and the power supply contact part 23 are flat with the upper surface of the support body 13.

[0068] Within the container body 7, the cylindrical body 20 extends downward toward the liquid 11. A discharge electrode 15 is provided at the lower end of the cylindrical body 20 so as to protrude downward. The cylindrical body 20 is made of conductive stainless steel (SUS304), which is the same material as the discharge electrode 15. By making the cylindrical body 20 and the discharge electrode 15 out of the same material, it is possible to prevent electrolytic corrosion (electrochemical corrosion) caused by contact between dissimilar metals.

[0069] The discharge electrodes 15 are provided intermittently at predetermined intervals along the circumferential direction of the cylindrical body 20. This allows the microorganisms in the air drawn into the container body 7 to be uniformly charged without bias. In the illustrated example, the discharge electrodes 15 are arranged in four bundles at 90 degree intervals, but other arrangements, such as six bundles at 60 degree intervals, may also be used.

[0070] The multiple discharge electrodes 15 are all formed to have approximately the same overall length, and the tips of the multiple discharge electrodes 15 are approximately aligned. Each discharge electrode 15 has a bundle 25 formed into a brush shape by bundling fibrous wire electrodes 24. The wire electrodes 24 are formed of non-magnetic stainless steel fibers with a diameter of 12 μm. This makes it easy for the wire electrodes 24 to separate from the bundle 25, and the discharge performance can be improved. In contrast, for example, in a magnetic ferrite-based material, it is difficult for the wire electrodes 24 to separate from the bundle 25, so the influence of electric field interference with the bundle 25 is large, making it difficult to generate a corona discharge with a strong electric field.

[0071] One discharge electrode 15 is formed, for example, by bundling about 100 wire electrodes 24. The discharge electrode 15 may be formed by bundling 10 to 200 wire electrodes 24 each having a diameter of 5 to 25 μm. The discharge electrode 15 may also be formed from carbon fiber having a diameter of 5 to 7 μm. Although the discharge electrode 15 is formed from the wire electrodes 24 in this embodiment, it may also be formed from a needle electrode or a plate electrode equipped with protrusions.

[0072] The voltage applied to discharge electrode 15 is several kV, specifically in the range of 4 to 6 kV. The length of discharge electrode 15 (the length protruding from cylindrical body 20) is several mm, specifically in the range of 3 to 7 mm. Therefore, stable discharge is possible even at a relatively low voltage.

[0073] A positive high voltage is applied to the discharge electrode 15 in the form of a direct current. By adopting a direct current method in this way, a relatively simple configuration can be achieved compared to other methods (alternating current, pulse). In particular, when collecting bioparticles such as microorganisms, bacteria, and viruses, the voltage applied to the electrode is set to a voltage (e.g., several kV) that does not destroy the cells of the bioparticles. Furthermore, by adopting a positive charging method as the high voltage application method, the generation of ozone can be suppressed compared to a negative charging method, and therefore the impact on bioparticles such as microorganisms, bacteria, and viruses can be reduced.

[0074] In the illustrated example, a high voltage that generates a corona discharge is applied to the discharge electrode 15, but induction charging may also be used in which a high voltage that does not generate a corona discharge (a voltage lower than the corona discharge voltage) is applied to charge the particles (all particles).

[0075] The discharge section 16 is provided with an outflow passage 26 formed by hollowing out the inside of the support 13. The outflow passage 26 has a cylindrical shape and is formed so as to penetrate the inside of the support 13 in the vertical direction. The outflow passage 26 is formed parallel to the cylinder 20 of the suction section 14 and is disposed so as to be as far away as possible from the cylinder 20 in a plan view. Note that the outflow passage 26 may be formed inside a cylinder housed inside the support 13.

[0076] The grounding portion 17 is conductive and formed in a vertically oval rod shape. The grounding portion 17 may be plate-like or cylindrical. The grounding portion 17 passes through the support 13 in the vertical direction, and an upper portion of the grounding portion 17 is supported by the support 13. An earth contact portion 27 having a slightly larger outer diameter is formed at the upper end of the grounding portion 17 (see FIG. 1). The grounding portion 17 is supported by the support 13 with the upper surface of the earth contact portion 27 being flat with the upper surface of the support 13.

[0077] Within the container body 7, the ground portion 17 extends downward toward the liquid 11, and is covered with a non-conductive, cylindrical insulating member 28 made of, for example, resin. Since the ground portion 17 is thus covered and protected by the insulating member 28 within the container body 7, it is possible to prevent the adhesion of charged particles to the ground portion 17.

[0078] An earth spring 29 is connected to the lower end of the grounding portion 17 as a conductive biasing member, and the earth spring 29 elastically contacts the bottom 10 of the container body 7. Therefore, even if there is variation in the distance from the opening 8 of the container body 7 to the liquid surface due to variations in the mounting condition of the support 13 or variations in the amount of stored liquid 11, the variation in distance is absorbed by the earth spring 29, so that the earth spring 29 comes into contact with the liquid 11 and can reliably ground the liquid 11. In the illustrated example, a coil spring is used as the biasing member, but a leaf spring may also be used.

[0079] 1, the upper surface of the electrode unit 12 is formed flat, and the suction portion 14, the discharge portion 16, and the ground portion 17 do not protrude from the upper surface of the electrode unit 12. Therefore, the lid 9 can be securely attached to the particle collection container 2, and the airtightness (sealing ability) of the inside of the container body 7 can be ensured.

[0080] Furthermore, by attaching the electrode unit 12 to the opening 8 of the container body 7, the process of accommodating the discharge electrode 15 in the container body 7 and the process of accommodating the grounding portion 17 in the container body 7 and bringing it into contact with the liquid 11 are carried out simultaneously, thereby making the work more efficient. <Power supply unit>

[0081] 2 to 4C, power supply unit 3 is provided above electrode unit 12 so as to be manually (or automatically) movable up and down (see the thick vertical arrows in FIG. 3), and after particle collection container 2 is set at a predetermined position in particle collection device 1, power supply unit 3 and electrode unit 12 are tightly connected when power supply unit 3 is lowered toward particle collection container 2. Power supply unit 3 is configured to include a support body 30, an intake flow path 31, an exhaust flow path 32, a power supply member 33, and a ground member 34.

[0082] The support 30 is made of a non-conductive material, for example, made of resin (or rubber). The support 30 has a cylindrical shape with the same diameter as the flange portion 19 of the support 13 of the electrode unit 12.

[0083] The suction flow passage 31 has a cylindrical shape and is formed so as to penetrate vertically inside the support 30. The suction flow passage 31 is disposed at a position corresponding to the inflow passage 22 of the suction section 14 of the electrode unit 12, and is capable of communicating with the inflow passage 22 of the suction section 14. An extension section 35 extending downward (toward the electrode unit 12) is formed at the lower end of the suction flow passage 31, and the extension section 35 is capable of being fitted into the upper end section of the cylinder 20 of the suction section 14.

[0084] The discharge flow passage 32 has a cylindrical shape, and is formed so as to penetrate vertically inside the support 30 in parallel with the suction flow passage 31. The discharge flow passage 32 is disposed at a position corresponding to the outflow passage 26 of the discharge section 16 of the electrode unit 12, and is capable of communicating with the outflow passage 26 of the discharge section 16. An extension section 36 extending downward (towards the electrode unit 12) is formed at the lower end of the discharge flow passage 32, similar to the suction flow passage 31, and the extension section 36 is capable of being fitted into the upper end of the outflow passage 26 of the discharge section 16.

[0085] Since the extension portions 35, 36 are formed in the suction flow path 31 and the exhaust flow path 32, respectively, when the power supply unit 3 and the electrode unit 12 are connected, the extension portion 35 of the suction flow path 31 of the power supply unit 3 fits into the suction portion 14 of the electrode unit 12, and the extension portion 36 of the exhaust flow path 32 of the power supply unit 3 fits into the exhaust portion 16 of the electrode unit 12, thereby preventing air leakage.

[0086] The power supply member 33 is made of a conductive material and formed into a cylindrical shape, penetrates vertically through the support 30, and is fixed at a position corresponding to the power supply contact 23 of the suction part 14 of the electrode unit 12. An upper end 37 of the power supply member 33 protrudes slightly above the upper surface of the support 30, and a high voltage is applied via this upper end 37. A lower end 38 of the power supply member 33 is formed to have a slightly smaller outer diameter, and a power supply spring 39 is wound and fixed around the outer periphery of the lower end 38. As a result, when the power supply unit 3 and the electrode unit 12 are closely attached to each other, the power supply spring 39 comes into contact with the power supply contact 23.

[0087] The grounding member 34, like the power supply member 33, is made of a conductive material and formed into a cylindrical shape, penetrates vertically through the support 30, and is fixed at a position corresponding to the earth contact portion 27 of the grounding portion 17 of the electrode unit 12. An upper end 40 of the grounding member 34 protrudes slightly upward from the upper surface of the support 30, and is adapted to be grounded via this upper end 40. A lower end 41 of the grounding member 34 is formed to have a slightly smaller outer diameter, and an earth spring 42 is wound and fixed around the outer periphery of the lower end 41. As a result, when the power supply unit 3 and the electrode unit 12 are in close contact with each other, the earth spring 42 comes into contact with the earth contact portion 27.

[0088] <Suction equipment> As shown in Fig. 3, the suction equipment 4 includes an upstream flow passage 43 connected to the suction flow passage 31 of the power supply unit 3, and an inlet 45 provided at the upstream end of the upstream flow passage 43. The inlet 45 is expanded in diameter in a funnel shape, making it easy to suck in air containing particles. Although not shown, the suction equipment 4 may include a pre-treatment filter for collecting relatively large particles such as dust, and a mist sprayer. When a mist sprayer (the solution to be sprayed is, for example, pure water) is provided, mist is sucked into the container body 7 together with air, so that even if the liquid evaporates, it can be replenished.

[0089] <Discharge equipment> 3, the exhaust equipment 5 includes a downstream flow passage 46 connected to the exhaust flow path 32 of the power supply unit 3, a pump 47 as suction means provided midway through the downstream flow passage 46, and an exhaust port (not shown) provided at the downstream end of the downstream flow passage 46. Although a fan may be used as the suction means, the pump 47 is preferable since it has a higher suction pressure. Although not shown, the exhaust equipment 5 may include a HEPA filter for collecting relatively small particles.

[0090] [Another type of particle collector] Next, another type of particle collecting device according to an embodiment of the present invention will be described with reference to Fig. 5 to Fig. 8. Fig. 5 is a perspective view showing another type of particle collecting container according to an embodiment of the present invention from diagonally above, Fig. 6 is an exploded perspective view showing another type of particle collecting container according to an embodiment of the present invention with an electrode unit removed from the particle collecting container from diagonally above, Fig. 7 is a cross-sectional view showing another type of particle collecting device according to an embodiment of the present invention, and Fig. 8 is a cross-sectional view taken along line XX in Fig. 7. In the description of another type of particle collecting device according to an embodiment of the present invention, for the sake of simplicity, the same components as those in the above-described particle collecting device 1 are denoted by the same reference numerals in Figs. 5 to 8 as in Figs. 1 to 4C, and detailed description thereof will be omitted.

[0091] In another type of particle collecting device 60 according to this embodiment, in addition to the same configuration as the above-described particle collecting device 1, a particle collecting container 2 is provided with a repulsion section 61 and a jetting plate 62. Also, the suction facility 4 is provided with an electromagnetic valve 44 as an opening / closing valve in the middle of the flow passage 43 on the upstream side.

[0092] <Repulsion part> The repulsion section 61 is composed of a repulsion plate 64 formed in a circular, flat plate shape, and the outer diameter of the repulsion plate 64 is set to be slightly smaller than the opening 8 of the container body 7. The repulsion plate 64 is fixed to the lower end of the cylindrical body 20 of the suction section 14, and is supported by the insulating member 28 of the grounding section 17 via a bush 65 which is a non-conductive insulator. The repulsion plate 64 has circular openings 66 and 67 formed in positions corresponding to the cylindrical body 20 and the bush 65, respectively (see FIG. 8).

[0093] The repulsion plate 64 is disposed so as to face the liquid surface inside the container body 7. The distance between the repulsion plate 64 and the liquid surface is set to be greater than the distance between the tip (lower end) of the discharge electrode 15 and the liquid surface. A gap is provided between the inner surface of the container body 7 and the outer periphery of the repulsion plate 64 as an air flow passage.

[0094] The voltage (high voltage) applied to the repulsion plate 64 is set to the same number of KV as the discharge electrode 15. The electrode unit 12 including the repulsion plate 64 can be housed in the container body 7 through the opening 8 of the container body 7 and can be removed to the outside of the container body 7. This makes it easy to handle the electrode unit 12. Furthermore, when the electrode unit 12 is removed from the container body 7, the upper part of the liquid layer (liquid film) is in an open state, so that the liquid 11 can be easily handled. Furthermore, it is also easy to form a liquid layer on a plate using a dropper or the like, and to collect the liquid 11 after particle collection.

[0095] <Gushing board> The ejection plate 62 is provided in an opening 66 formed in a portion of the rebound plate 64 corresponding to the cylindrical body 20. The ejection plate 62 is disposed at a position facing the liquid surface at a predetermined distance from the liquid surface. A small-diameter ejection port 68 is formed in the center of the ejection plate 62 for forcing air out. The aperture of the ejection port 68 is set to a diameter of 1 mm or less, and for example, when the inner diameter of the cylindrical body 20 is about 10 mm, it is set to about 0.5 mm.

[0096] In the illustrated example, a jet plate 62 is provided, but instead of the jet plate 62, for example, a sloped portion 69 may be provided so that the opening area gradually decreases from the upstream side to the downstream side of the cylinder 20 of the suction section 14 (see dashed line in Figure 7).

[0097] In the illustrated example, the repulsion plate 64 and the ejection plate 62 are disposed at the same height at the lower end of the cylinder 20 of the suction section 14, so the repulsion plate 64 and the ejection plate 62 may be integrated into one circular plate. Furthermore, various modifications other than those described above are possible, such as providing only one of the ejection plate 62 and the repulsion plate 64.

[0098] <Modifications of the suction section> 9 shows a suction section 70 of a modified example of the above-described particle collector 1 or another type of particle collector 60. The suction section 70 of this modified example is provided with a discharge electrode 71 formed in a sawtooth shape around the lower end of the cylindrical body 20, instead of the above-described brush-like discharge electrode 15. The discharge electrode 71 is formed with a sharp tip, which generates a non-uniform electric field at the tip and allows the electric field to be concentrated, thereby charging the particles.

[0099] <Control device> As shown in FIG. 10, the control device 6 includes a control unit 80, which is configured by connecting a CPU 81, a storage unit 82, and an interface unit 83 to each other via a bus 84. A display unit 85, a setting operation unit 86, an operation / stop switch 87, a limit switch 88, a pump 47, a voltage supply unit 89, an electromagnetic valve 44, and the like are connected to the control unit 80 via the interface unit 83. Although not shown, a battery is mounted as a power source. Although not shown, the control device 6 may also include a cooling means (e.g., a Peltier element) for cooling the container body 7 (particularly the bottom portion 10 in which the liquid 11 is stored). The cooling means can cool the liquid 11 stored in the container body 7, thereby preventing the liquid from evaporating.

[0100] When the operation / stop switch 87 is turned ON, the pump 47 starts sucking in air, and a predetermined high voltage is applied by a voltage supply unit 89 to the discharge electrodes 15, 71 and the repulsion unit 61. At this time, a limit switch 88 (safety switch) detects whether or not the particle collection container 2 is accommodated in a predetermined position, and the pump 47 does not start the suction operation unless the limit switch 88 is turned ON. The pump 47 may be controlled so as to stop the suction operation after sucking in air for a preset operating time.

[0101] [Particle collection method] Next, a particle collecting method for collecting particles in the air using the particle collecting device 1, 60 will be described with reference to Figs.

[0102] The particle collection method according to the embodiment of the present invention includes a liquid supplying step of removing the lid 9 of the particle collection container 2 and supplying a conductive liquid 11 into the container body 7 from the opening 8, a collection container installation step of setting the particle collection container 2 with the electrode unit 12 attached to the opening 8 in a storage section of the particle collection container 2 after the liquid supplying step and manually or automatically connecting the power supply unit 3 to the electrode unit 12, an air suction step of starting the operation of the particle collection device 1, 60 after the collection container installation step to suck air containing particles into the container body 7, a particle charging step of charging the particles in the air sucked in the air suction step by applying a high voltage to the discharge electrode 15 (and the repulsion section 61), and a particle collection step of causing the liquid 11 supplied into the container body 7 to collect the particles charged in the particle charging step. The air suction step, the particle charging step, and the particle collection step are performed according to a continuous operation or an intermittent operation described below.

[0103] <Continuous operation> First, the action of the particle collecting device 1 during continuous operation will be described with reference to FIGS.

[0104] In the case of continuous operation, when the operation / stop switch 87 is turned ON, a command from the CPU 81 is issued so that a high voltage V1 is applied from the voltage supply section 89 to the discharge electrode 15 of the electrode unit 12 via the power supply member 33 of the power supply unit 3, and the pump 47 is driven.

[0105] By driving the pump 47, dust-laden air containing particles such as bioparticles and dust is sucked from the suction port 45 through the suction flow path 31 and the cylinder 20 of the suction part 14 into the container body 7, where it descends, then diffuses around along the liquid surface and passes between the discharge electrodes 15 and the liquid surface. At this time, a charged area EA is formed between the lower end (tip) of each discharge electrode 15 and the liquid surface due to corona discharge generated between the lower end (tip) of the discharge electrodes 15 and the liquid surface.

[0106] Particles in the air that pass between the discharge electrodes 15 and the liquid surface become charged by passing through a charged area EA formed between the lower end (tip) of each discharge electrode 15 and the liquid surface by corona discharge, and are attracted to the liquid surface and collected in the liquid 11.

[0107] The clean air from which particles have been trapped and removed in this manner in the liquid 11 passes through the outlet passage 26 of the exhaust section 16 of the electrode unit 12 and the exhaust flow path 32 of the power supply unit 3, and then through the flow passage 46 of the exhaust equipment 5, and is discharged to the outside through the exhaust port.

[0108] Thereafter, when the run / stop switch 87 is turned OFF, the application of high voltage to the discharge electrode 15 is stopped by a command from the CPU 81, and the pump 47 is stopped.

[0109] <Intermittent operation> Next, with reference to Figs. 7, 10, and 11, an operation during intermittent operation performed in the particle collector 60 when high collection efficiency is required will be described.

[0110] In the case of intermittent operation, when the operation / stop switch 87 is turned ON, the solenoid valve 44 is switched from a closed state to an open state in response to a command from the CPU 81, and a high voltage V1 is applied from the voltage supply section 89 to the discharge electrode 15 and the repulsion plate 64 via the power supply member 33 of the power supply unit 3, thereby driving the pump 47.

[0111] When the pump 47 is driven, particles in the dust-laden air sucked into the container body 7 are charged as they pass through the charging area EA, and are attracted to the liquid surface, repelled by the repulsion plate 64, and are attracted to the liquid surface side, where they are collected in the liquid 11.

[0112] 11, when the operation / stop switch 87 is turned ON, after the pump 47 is driven, both the timing at which the solenoid valve 44 is switched from the closed state to the open state and the timing at which a high voltage is applied to the discharge electrode 15 may be delayed by time T3. This makes it possible to reduce the internal pressure of the particle collection container 2 (-Pmax), thereby increasing the speed of the air flowing into the particle collection container 2 and increasing the degree of mixing of the particles in the air with the liquid 11.

[0113] Thereafter, the solenoid valve 44 is repeatedly switched from the closed state (T2) to the open state (T1) at predetermined intervals in response to a command from the CPU 81. Note that the interval T2 during which the solenoid valve is in the closed state is set to be shorter than the interval T1 during which the solenoid valve is in the open state.

[0114] When the solenoid valve 44 is switched from the open state to the closed state in this manner, the internal pressure of the particle collection container 2 decreases, and when the solenoid valve 44 is subsequently switched from the closed state to the open state, air flows forcefully from the nozzle 68 of the nozzle plate 62 toward the liquid surface, thereby increasing the degree of mixing of the particles in the air with the liquid 11.

[0115] The clean air from which particles have been trapped and removed in this manner in the liquid 11 passes through the outlet passage 26 of the exhaust section 16 of the electrode unit 12 and the exhaust flow path 32 of the power supply unit 3, and then through the flow passage 46 of the exhaust equipment 5, and is discharged to the outside through the exhaust port.

[0116] Thereafter, when the run / stop switch 87 is turned OFF, the solenoid valve 44 is switched to the closed state in response to a command from the CPU 81, the application of high voltage is stopped, and the pump 47 is stopped.

[0117] In the above explanation of the operation of the particle collectors 1 and 60, the operation has been described in the case where the particle collector 1 is operated continuously and the particle collector 60 is operated intermittently. However, for example, the particle collector 1 may be operated intermittently by providing the solenoid valve 44 in the suction facility 4, or the particle collector 60 may be operated continuously.

[0118] [Particle collection procedure] Next, a procedure for extracting the particles collected in the liquid 11 from the particle collection container 2 as described above will be described.

[0119] First, as shown in FIGS. 3 and 7, the power supply unit 3 is manually or automatically raised to separate it from the electrode unit 12, and the particle collection container 2 is removed from the particle collection device 1, 60. After that, the lid 9 (see FIG. 1) is attached to the particle collection container 2 and it is stored until moving to the next process.

[0120] In the next step, the lid 9 is removed from the particle collection container 2, and the electrode unit 12 attached to the opening 8 of the container body 7 is removed. Since there is a risk of viruses adhering to the electrode unit 12, the electrode unit 12 is disposable and discarded. Thereafter, a pipette (dropper) or the like is used to collect the liquid in which the particles have been collected from inside the container body 7 through the opening 8, and the collected liquid is measured in the next step (e.g., PCR processing).

[0121] It should be noted that the above-described embodiments are preferred specific examples of the present invention, and may include various technically preferable limitations, but the technical scope of the present invention is not limited to these aspects unless there is a specific description that limits the present invention. [Industrial Applicability]

[0122] The technology of the present invention can be suitably used in air samplers and airborne bacteria measuring devices that collect microorganisms, bacteria, and viruses in the air and measure the number of microorganisms, bacteria, and viruses. [Explanation of symbols]

[0123] 1 Particle collection device 2. Particle collection vessel 3 Power supply unit 7 Container body 8 Openings 11 liquid 14 Suction section 15 Electrode for discharge 16 Discharge section 17 Grounding part 20 cylinder 22 Inflow channel 24 wire electrode 25 Bundle part 26 Outflow channel 28 Insulating materials 9. Earth spring (biasing member) 31 Suction passage 32 Exhaust flow path 33 Power supply components 34 Grounding member 37 Upper end 44 Solenoid valve (on-off valve) 47 Pump (suction means) 50 Media storage section 61 Repulsion part 65 Bush (insulator)

Claims

1. A particle collection container that collects particles in the air by charging them, A container body having an opening; a suction section provided at the opening and having an inlet passage for introducing air from the outside of the container body to the inside of the container body; a discharge part provided at the opening and having an outlet path for discharging air from the inside of the container body to the outside; a discharge electrode provided inside the container body and to which a high voltage is applied; a medium storage section provided inside the container body and capable of storing a medium for collecting particles in the air charged by the discharge electrode; Equipped with The medium is liquid or gel-like, A particle collection container, characterized in that the medium storage section is capable of storing the medium in a film-like form on a bottom portion.

2. 2. The particle collection vessel according to claim 1, wherein the medium is a conductive liquid.

3. 3. The particle collection container according to claim 2, characterized in that the suction section has a conductive cylindrical body having one end open to the outside of the container body and the other end open to the inside of the container body, and the discharge electrode is provided at the other end of the cylindrical body facing the liquid.

4. 4. The particle collection container according to claim 3, wherein an opening area of ​​the other end of the suction portion is set smaller than an opening area of ​​the one end of the suction portion.

5. 5. The particle collection vessel according to claim 2, wherein the discharge electrode is constituted by a wire electrode having a bundle portion formed by bundling fibers.

6. The particle collection container according to any one of claims 2 to 5, characterized in that the discharge electrodes are arranged at equal intervals along a circumferential direction of the suction portion, and a tip of each discharge electrode is provided protruding from the suction portion toward the liquid surface side of the liquid and is arranged at a position spaced a certain distance from the liquid surface.

7. The particle collection container according to any one of claims 2 to 6, further comprising a grounding portion extending from an opening of the container body toward the inside and in contact with the liquid, and an outer periphery of the grounding portion is covered with a non-conductive insulating member.

8. 8. The particle collection container according to claim 7, wherein a conductive biasing member is provided at an end of the grounding portion on the liquid side.

9. 9. The particle collection container according to claim 7, wherein the suction portion is provided with a repulsion portion, the repulsion portion being provided along the liquid surface at a position spaced a certain distance from the liquid surface.

10. The particle collection container according to claim 9, characterized in that the repulsion portion has a planar shape similar to and smaller than the opening of the container body, and is supported at the other end of the suction portion and also supported at the ground portion via an insulator.

11. The particle collection container according to any one of claims 2 to 10, characterized in that the main component of the liquid is water, the liquid is formed as a liquid film having a thickness of 1 mm or less, and contains a surfactant.

12. 12. The particle collection vessel according to claim 2, wherein the liquid contains an antioxidant.

13. 13. The particle collection vessel according to claim 2, wherein the liquid contains a salt having deliquescent properties.

14. The particle collection container according to any one of claims 1 to 13, characterized in that the opening of the container body is formed in an upper part opposite to a bottom of the container body, the bottom is formed flat, and the inner surface of the container body is water-repellent.

15. 15. The particle collection container according to claim 1, wherein the container body is a vial.

16. The particle collection container according to any one of claims 2 to 15, further comprising an electrode unit provided with the suction portion having the discharge electrode and a power supply contact portion, the discharge portion, and a grounding portion in contact with the liquid, the electrode unit being detachably provided at an opening of the container body.

17. 17. The particle collection container according to claim 16, wherein an upper surface of the electrode unit is formed flat, and the suction portion, the discharge portion and the grounding portion do not protrude beyond the upper surface of the electrode unit.

18. A particle collecting device comprising the particle collecting container according to any one of claims 1 to 17, A power supply unit is provided which is detachable from the particle collection container, and the power supply unit includes: A suction passage capable of communicating with the inlet passage of the suction portion; A discharge flow path capable of communicating with the outlet path of the discharge portion; a power supply member capable of coming into contact with a power supply contact portion formed on the suction portion; a grounding member capable of contacting a grounding portion that contacts the medium; A particle collecting device comprising:

19. an on-off valve provided in a flow passage upstream of the suction flow passage of the power supply unit; a suction means provided in a flow passage downstream of the exhaust flow passage of the power supply unit; Equipped with 20. The particle collecting apparatus according to claim 18, wherein, during operation, the suction means operates continuously, and the on-off valve is controlled to alternately open and close.

20. 20. The particle collecting device according to claim 19, wherein, during operation, the on-off valve is controlled so that the time during which it is in an open state is longer than the time during which it is in a closed state.

21. A method for collecting particles in air using the particle collecting device according to claim 18 or 19, comprising the steps of: a medium supplying step of supplying the medium into the container body; an air suction step of sucking air containing particles into the container body after the medium supply step; a particle charging step of charging particles in the air sucked in the air sucking step by applying a high voltage to the discharge electrode; a particle collecting step of collecting the particles charged in the particle charging step by the medium supplied into the container body in the medium supplying step; A method for collecting particles, comprising:

22. 22. The method of claim 21, wherein the particles include microorganisms, bacteria, or viruses.

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