Patent Description:
A cyclone collector is conventionally known which includes a container that forms a cylindrical space, and in which a liquid film is formed on the interior surface of the container. The cyclone collector causes particles in an intake gas to adhere to the liquid film, thereby collecting the particles (see <CIT>).

However, if a gas inlet opens at a position near the liquid film, a mist will be generated from the liquid film. The mist is discharged through an exhaust pipe, resulting in a decrease in the collection efficiency. On the other hand, if an intake gas from the gas inlet hits an area which is at a distance from the liquid film and in which no liquid film is formed, particles in the intake gas cannot be securely collected in the liquid film.

Further previously known cyclone collectors are derivable from <CIT>, on which the two-part form of claim <NUM> is based, <CIT>, <CIT>, <CIT> as well as <CIT>.

The present invention has been made in view of the above situation. It is therefore an object of the present invention to provide a cyclone collector which can securely collect particles from an intake gas and which will not discharge a mist.

The above-described problems are solved by means of a cyclone collector according to claim <NUM>.

In a preferred embodiment of the present invention, the gas inlet is provided in the upper-end portion of the container.

In a preferred embodiment of the present invention, the liquid-film forming section forms the liquid film on the interior surface of the side wall such that it extends upward from the lower-end portion of the container.

In a preferred embodiment of the present invention, the gas inlet is provided in plural numbers.

In a preferred embodiment of the present invention, the gas inlet is provided in the upper-end portion of the container, and the opening opens into the space in the container.

In a preferred embodiment of the present invention, the gas inlet is provided in the upper-end portion of the container, and has a projecting nozzle which projects from the surface of the upper-end portion and which, at its front end, has said opening.

In a preferred embodiment of the present invention, a liquid supply section is mounted to the lower-end portion of the container.

In a preferred embodiment of the present invention, a liquid supply section is mounted to the side wall of the container. Advantageous Effects of the Invention.

According to the present invention, it becomes possible to securely collect particles from an intake gas, and to prevent discharge of a mist.

A first embodiment of the present invention will now be described in detail. The below-described embodiments should not be construed to limit the scope of the invention disclosed herein. Further, the embodiments may be appropriately combined as long as it does not create a contradiction.

A cyclone body <NUM> of a cyclone collector <NUM> according to the present invention consists of a revolution body having an axis of rotation (also referred to as an axis) 21A. As used herein, the terms "upward", "upper end", "downward" and "lower end" refer to "upward", "upper end", "downward " and "lower end" in the case where the cyclone body <NUM> of the cyclone collector <NUM> according to the present invention is installed such that the axis of rotation 21A extends in the vertical and longitudinal direction (see <FIG>).

At the outset, the entire measuring apparatus <NUM>, in which the cyclone collector <NUM> according to the present invention is incorporated, will be described with reference to <FIG>.

<FIG> is a schematic view showing the overall construction of the measuring apparatus. <FIG> illustrates a case in which the measuring apparatus <NUM> detects detection target particles based on the fluorescence intensities of droplets. However, the present invention is not limited to such a case. For example, the measuring apparatus <NUM> may only perform measurement of the fluorescence intensities of droplets. In that case, based on the fluorescence intensities measured by the measuring apparatus <NUM>, the user or another apparatus will determine whether detection target particles are contained in an analyte gas. The detection target particles are, for example, virus particles, bacteria particles, pollen particles, particles of a toxic substance, etc.; however, the detection target particles are not limited to these as long as a fluorescent substance can specifically bind to the target particles.

As shown in <FIG>, in this embodiment the measuring apparatus <NUM> includes a dust removal section <NUM>, a main pipe <NUM>, a collection section (also referred to as a cyclone collector) <NUM> according to the present invention, a droplet forming section <NUM>, a droplet sorting section <NUM>, a measuring section <NUM>, a liquid recovery section <NUM>, and a suction pump <NUM>.

Next, a positional relationship between the components will be described briefly. The main pipe <NUM> is a guide passage for a gas flow. The dust removal section <NUM> is disposed upstream in a gas flow which is guided by the main pipe <NUM>. The suction pump <NUM> is a gas flow forming mechanism for forming a gas flow in the main pipe <NUM>, and is disposed downstream in the gas flow which is guided by the main pipe <NUM>. In other words, the suction pump <NUM> is configured to form a gas flow that flows from the dust removal section <NUM> to the suction pump <NUM> in the main pipe <NUM>. It is also possible to provide, as a gas flow forming mechanism, a gas feed pump upstream of the dust removal section <NUM>. In that case, compressed air may be supplied from the gas feed pump into the main pipe <NUM>.

The droplet forming section <NUM>, the droplet sorting section <NUM>, the measuring section <NUM> and the liquid recovery section <NUM> are provided in this order between the dust removal section <NUM> and the suction pump <NUM> in the main pipe <NUM>.

Next, the construction of each component will be described. The dust removal section <NUM> has a degree of gas flow resistance which is necessary to form aerosol droplets in the main pipe <NUM>. The dust removal section <NUM> is configured to be capable of supplying a clean gas by capturing particles that affect the measurement.

The collection section <NUM> consisting of a cyclone collector will now be described. The collection section <NUM> is configured to collect, in a liquid, detection target particles contained in an analyte gas, and to cause a fluorescent substance, which specifically binds to the detection target particles, to bind to the detection target particles in the liquid.

In this embodiment, as shown in <FIG>, the collection section <NUM> includes a cyclone body (also referred to as a container) <NUM>, a gas introduction section <NUM> for introducing a gas into the cyclone body <NUM>, and a liquid introduction section <NUM> for introducing a liquid into the cyclone body <NUM>.

The cyclone body <NUM> has a truncated cone-shaped interior surface (hereinafter referred to as a wall surface), and is oriented such that the small-diameter end is located below the large-diameter end.

The gas introduction section <NUM> is provided on an upper portion of the cyclone body <NUM> such that it extends in a direction tangent to the wall surface of the cyclone body <NUM>, and is airtightly coupled to a coarse dust removal section <NUM>. The direction tangent to the wall surface herein refers to a direction tangent to a circle which is defined when the cyclone body <NUM> is cut off in a horizontal direction, which is perpendicular to the axis of the cyclone body <NUM>, in a portion where a gas, introduced in the below-described manner, hits (collides against) the wall surface of the cyclone body <NUM>. The coarse dust removal section <NUM> is configured to collect relatively large particles, such as dust and fibers, while allowing passage of analyte particles. The gas, which has been introduced from the coarse dust removal section <NUM> into the cyclone body <NUM> through the gas introduction section <NUM>, is guided along the wall surface of the cyclone body <NUM> so that the gas swirls in the circumferential direction.

The liquid introduction section <NUM> includes a tank 23a for storing a liquid, a liquid introduction pipe 23b which, at its one end, is connected to the bottom of the tank 23a and, at the other end, is connected to the wall surface of the cyclone body <NUM>, and a flow rate control section 23c provided in the liquid introduction pipe 23b.

In this embodiment, the tank 23a stores a liquid containing a fluorescent substance. The fluorescent substance is, for example, a fluorescence-labeled antibody. As shown in <FIG>, a fluorescence-labeled antibody Y uses an antibody-antigen reaction to specifically bind to a particular detection target particle P.

As shown in <FIG>, the fluorescent substance may take the form of an agglomerated antibody particle A whose surface is modified with a plurality of fluorescence-labeled antibodies Y. In this case, the fluorescence-labeled antibodies Y in the surface of the antibody particle A each use an antibody-antigen reaction to specifically bind to a particular detection target particle P. Thus, a plurality of detection target particles P can be agglomerated via the agglomerated antibody particle A. This makes it possible to increase the volume density of fluorescence-labeled antibodies Y, thereby enhancing the fluorescence intensity.

The above-mentioned other end of the liquid introduction pipe 23b is connected to the wall surface of the cyclone body <NUM> at a position lower than the gas introduction section <NUM>. On the other hand, the above-mentioned one end of the liquid introduction pipe 23b is disposed at a position higher than the above-mentioned other end. When the flow rate control section 23c is opened, the liquid stored in the tank 23a is allowed by gravity to flow through the liquid introduction pipe 23b into the cyclone body <NUM>.

The liquid introduction section <NUM> is not limited to such a construction. For example, the liquid introduction section <NUM> may include a syringe pump storing a liquid containing a fluorescent substance. The front end of the syringe is coupled to the wall surface of the cyclone body <NUM> so that when the interior of the syringe is pressurized by a piston, the fluorescent substance-containing liquid is introduced into the cyclone body <NUM>.

In this embodiment, above the cyclone body <NUM> is provided a suction/exhaust section <NUM> for exhausting by suction and thereby depressurizing the interior of the cyclone body <NUM> so that by the differential pressure, a gas will be introduced from the gas introduction section <NUM> into the cyclone body <NUM> in such a manner that the gas swirls in the circumferential direction.

The suction/exhaust section <NUM> includes a suction/exhaust pipe (also referred to as an exhaust pipe) 24b concentrically inserted into an upper portion of the cyclone body <NUM>, and a suction/exhaust pump 24a provided for the suction/exhaust pipe 24b.

When the suction/exhaust pump 24a is actuated, the interior of the suction/exhaust pump 24a is exhausted by suction and depressurized through the suction/exhaust pipe 24b and, by the differential pressure between the inside and the outside of the cyclone body <NUM>, the gas outside the cyclone body <NUM> is forced through the coarse dust removal section <NUM> and drawn from the gas introduction section <NUM> into the cyclone body <NUM>. The gas which has been introduced into the cyclone body <NUM> is guided along the wall surface of the cyclone body <NUM>, so that the gas descends while swirling in the circumferential direction, i.e. the gas forms a swirling gas flow. Detection target particles in the gas have a relatively high specific gravity, and therefore the detection target particles are separated toward the wall surface of the cyclone body <NUM> due to centrifugal force.

On the other hand, the gaseous component having a relatively low specific gravity reverses its flow direction at the bottom of the cyclone body <NUM> due to the truncated conical shape of the cyclone body <NUM> and forms an upward flow along the central axis of the cyclone body <NUM>, and is discharged to the outside through the suction/exhaust pipe 24b.

The liquid that has been introduced from the liquid introduction section <NUM> into the cyclone body <NUM> is forced outward by the gas flow swirling in the circumferential direction, and forms a liquid film along the wall surface (interior surface) of the cyclone body <NUM>. The liquid introduction section <NUM> thus functions as a liquid-film forming section for forming a liquid film on the interior surface of the cyclone body <NUM>.

In this embodiment, a liquid-level detector <NUM> is provided for detecting the level of the liquid formed in the shape of a film on the wall surface of the cyclone body <NUM>. The flow rate control section 23c of the liquid introduction section <NUM> controls the flow rate of the liquid based on the results of detection by the liquid-level detector <NUM>.

In particular, the liquid-level detector <NUM> includes a pair of electrodes exposed in the interior of the cyclone body <NUM>, and a measurement section for measuring the electrical conductivity between the electrodes. When the level of the liquid is higher than the height position of the pair of electrodes, electricity passes between the pair of electrodes through the liquid; thus, the electrical conductivity is relatively high. On the other hand, when the level of the liquid is lower than the height position of the pair of electrodes, the pair of electrodes are insulated from each other; thus, the electrical conductivity is relatively low. An electrical conductivity in the case where the level of the liquid is higher than the height position of the pair of electrodes and an electrical conductivity in the case where the level of the liquid is lower than the height position of the pair of electrodes are experimentally determined in advance, and a value intermediate between the two measurement values is determined as a threshold. When an electrical conductivity, later measured by the measurement section, is higher than the threshold, then the level of the liquid is determined to be higher than the height position of the pair of electrodes. When an electrical conductivity, later measured by the measurement section, is lower than the threshold, then the level of the liquid is determined to be lower than the height position of the pair of electrodes.

When the liquid-level detector <NUM> determines that the level of the liquid is lower than the height position of the pair of electrodes, the flow rate control section 23c increases the flow rate of the liquid until the level of the liquid becomes higher than the height position of the pair of electrodes. This can prevent the gas-contact area of the liquid in the cyclone body <NUM> from decreasing due to discharge or evaporation of the liquid.

A liquid supply section <NUM> is connected to the bottom of the cyclone body <NUM>. The liquid supply section <NUM> is provided with a feed pump <NUM>.

The feed pump <NUM> discharges the liquid from the liquid supply section <NUM> while applying a pressure to the liquid. Therefore, though the interior of the cyclone body <NUM> is depressurized by the suction/exhaust section <NUM>, the liquid can be continuously and stably supplied from the cyclone body <NUM> to the droplet forming section <NUM> via the liquid supply section <NUM>.

Though not essential, the collection section <NUM> may be equipped with a heating mechanism for heating the liquid. When the reactivity of the fluorescent substance is low in a low temperature environment, e.g. in cold climates, the fluorescent substance in the liquid can be activated and the reaction rate can be increased by heating the liquid up to, for example, around body temperature (about <NUM> ° C).

Alternatively, the collection section <NUM> may be equipped with a cooling mechanism (not shown) for cooling the liquid. When the reactivity of the fluorescent substance is low in a high temperature environment, e.g. in extremely hot climates, the fluorescent substance in the liquid can be activated and the reaction rate can be increased by cooling the liquid down to, for example, around body temperature (about <NUM>).

Next, the droplet forming section <NUM> will be described. The droplet forming section <NUM> is configured to form aerosol droplets from the liquid supplied from the collection section <NUM>. In particular, the droplet forming section <NUM> is configured to form aerosol droplets from the liquid, supplied from the collection section <NUM>, by using at least one (two-fluid nozzle) of a nebulizer, an electrospray, a twin-fluid nozzle, a piezoelectric element, ultrasonic waves, and a decompression treatment.

In this embodiment, as shown in <FIG>, the droplet forming section <NUM> includes a narrowed portion 18a where the bore of the main pipe <NUM> is sharply narrowed. The end of the liquid supply section <NUM> is coaxially inserted into the narrowed portion 18a. The speed of a gas flow, flowing in the main pipe <NUM>, increases when it flows through the narrowed portion 18a. The fast gas flow, flowing through the narrowed portion 18a, creates a negative pressure at the end of the liquid supply section <NUM>. The negative pressure sucks and tears the liquid in the liquid supply section <NUM>, whereby aerosol droplets are formed from the liquid supplied from the liquid supply section <NUM>.

Though in the embodiment illustrated in <FIG>, the end of the liquid supply section <NUM> is coaxially inserted into the narrowed portion 18a, the present invention is not limited to this feature. For example, as shown in <FIG>, the end of the liquid supply section <NUM> may be orthogonally coupled to the narrowed portion 18a.

Next, the droplet sorting section <NUM> will be described. The droplet sorting section <NUM> is configured to sort out droplets having a diameter of less than a predetermined value from the droplets supplied from the droplet forming section <NUM>.

For example, a spray chamber which uses inertial force to sort out droplets having a diameter of less than a predetermined value can be used as the droplet sorting section <NUM>. More specifically, the spray chamber may be one selected from the group consisting of a cyclone spray chamber, a Scott-type spray chamber and an inertia branch-type spray chamber. Such spray chambers are known per se in the art of inductively coupled plasma (ICP) emission spectroscopic analysis and described, for example, in JIS K0133. However, this embodiment does not achieve the effect of sorting out droplets, having such a diameter as to be resolvable by inductively coupled plasma, by solely using a spray chamber, but achieves the following effect: As described later, the use of a spray chamber is combined with the technique of using a fluorescent substance which specifically binds to detection target particles. The combination increases the difference between the fluorescence intensity of a droplet containing no detection target particle and the fluorescence intensity of a droplet containing a detection target particle, thereby making it possible to detect target particles with high accuracy. This effect is unexpected from conventionally known spray chambers.

<FIG> is a schematic view showing an example of the construction of the droplet sorting section <NUM>. The droplet sorting section <NUM> shown in <FIG> is a cyclone spray chamber and includes a central chamber body 14a having a cylindrical interior surface, an upper chamber body 14b coupled to the upper end of the central portion and having a truncated conical interior surface, and a lower chamber body 14c coupled to the lower end of the central portion and having a truncated conical interior surface.

The main pipe <NUM> is connected to the interior surface of the central chamber body 14a such that it extends in a direction tangent to the interior surface. The gas flow containing droplets, which has flown through the main pipe <NUM> and has been introduced into the central chamber body 14a, is guided along the interior surface of the central chamber body 14a due to inertial force and swirls in the circumferential direction. Droplets having a diameter of not less than the predetermined value are separated toward the interior surface of the central chamber body 14a due to centrifugal force, hitting and adhering to the interior surface. In this manner, droplets having a diameter of not less than the predetermined value are removed from the gas flow, while droplets having a diameter of less than the predetermined value are carried by the gas flow and supplied from the top of the upper chamber body 14b to the measuring section <NUM>. The droplets (liquid) that have adhered to the interior surface of the central chamber body 14a flow down by gravity into the lower chamber body 14c, and are discharged to the outside from the bottom of the lower chamber body 14c. In cases where only a small amount of droplets (liquid) adhere to the interior surface of the central chamber body 14a, the adhering droplets (liquid) will evaporate. Therefore, there is no need to provide a liquid discharge mechanism.

Since a spray chamber uses inertial force to sort out droplets, the upper limit of the diameters of droplets to be sorted out by the spray chamber is correlated with dynamic parameters such as the size and the shape of the spray chamber, the speed of the gas flow, etc. Accordingly, the upper limit of the diameters of droplets to be sorted out by the spray chamber can be set to a desired value by appropriately selecting dynamic parameters such as the size and the shape of the spray chamber, the speed of the gas flow, etc. While the diameter of droplets to be sorted out by the spray chamber can be appropriately selected depending on the measuring object and the measurement purpose, it is preferably not more than <NUM>, more preferably not more than <NUM> when the measuring object is virus or bacteria.

Next, the measuring section <NUM> will be described. <FIG> is a schematic view showing an example of the construction of the measuring section <NUM>. The measuring section <NUM> is configured to irradiate a droplet with light and measure the fluorescence intensity of the droplet.

In this embodiment, as shown in <FIG>, the measuring section <NUM> includes a case body <NUM>, e.g. having a rectangular shape, connected to the main pipe <NUM> and which forms a space that allows passage of a gas flow containing droplets that have been sorted out by the droplet sorting section <NUM>. Light transmissive windows 52a, 52b made of quartz, which are parallel to each other, are disposed e.g. in the upper and lower walls (or the side walls) of the case body <NUM> which oppose each other.

Outside one light transmissive window 52a is provided a light-emitting section <NUM> for emitting laser light, having a wavelength which is different from the wavelength of the fluorescence emitted by the fluorescent substance, into the case body <NUM>. Outside the other light transmissive window 52b is provided an optical filter <NUM> for blocking the light having a wavelength which is different from the wavelength of the fluorescence emitted by the fluorescent substance. Outside the optical filter <NUM> is provided a light-receiving section <NUM> for receiving the fluorescence of the fluorescent substance and converting it into an electrical signal. The light-receiving section <NUM> is, for example, a photomultiplier tube and configured to output, to a received-light output measuring section <NUM>, for example an electric current of a signal level corresponding to the intensity of the light received from the optical filter <NUM>.

The received-light output measuring section <NUM> is configured to, for example, convert an electric current into a voltage and compare a voltage signal Ia, which indicates the voltage after conversion, with a preset threshold Is and, when the voltage signal Ia is determined to be higher than the threshold Is, issue an alarm indicating detection of detection target particles or display the alarm on a not-shown display.

For the voltage signal Ia which is a signal corresponding to the intensity of the received light, the threshold Is can be determined as follows. The threshold Is is set to an intermediate value between a fluorescence intensity as measured when droplets, formed by the droplet forming section <NUM> in the case where no detection target particles are present in the analyte gas, pass through the case body <NUM> and a fluorescence intensity as measured when droplets, formed by the droplet forming section <NUM> in the case where detection target particles are contained in the analyte gas and the fluorescent substance is bonded to the detection target particles, pass through the case body <NUM>. The fluorescence intensity, measured when no detection target particles are present in the analyte gas, corresponds to the intensity of fluorescence from the fluorescent substance adhering to dust contained in the gas passing through the case body <NUM>, or to the intensity of fluorescence from the fluorescent substance contained in droplets containing no detection target particles. The fluorescent substance specifically binds to detection target particles. Therefore, roughly speaking, the density of the fluorescent substance is higher when detection target particles are present. Thus, a difference in the fluorescence intensity exists between the presence and absence of detection target particles.

Returning to <FIG>, the liquid recovery section <NUM>, e.g. comprised of a mesh body, for capturing droplets that have passed through the measuring section <NUM> is provided downstream of the measuring section <NUM>. The suction pump <NUM> is provided downstream of the liquid recovery section <NUM> so that the gas, which has passed through the liquid recovery section <NUM>, is discharged to the outside of the measuring apparatus <NUM> via a not-shown filter for removing by adsorption detection target particles. The liquid recovery section <NUM> is provided with a liquid discharge mechanism. However, in cases where the amount of droplets (liquid) passing through the liquid recovery section <NUM> is sufficiently small, the droplets (liquid) will evaporate; therefore, there is no need to provide a liquid discharge mechanism.

The collection section <NUM>, consisting of the cyclone collector incorporated in the measuring apparatus <NUM>, will now be described with reference to <FIG> and <FIG>.

<FIG> is a side view of the cyclone body <NUM> of the collection section <NUM>, <FIG> is a bottom view of a lid as viewed from line A-A' of <FIG> is a cross-sectional view on line B-B' of <FIG>, showing the cyclone body <NUM>. <FIG> are each a perspective view of the cyclone body.

As described above, the collection section <NUM> includes the cyclone body (also referred to as the container) <NUM>, the gas introduction section <NUM> for introducing a gas into the cyclone body <NUM>, and the liquid introduction section (also referred to as the liquid-film forming section) <NUM> for introducing a liquid into the cyclone body <NUM> and forming a liquid film <NUM> on the interior surface of the cyclone body <NUM>.

More specifically, as shown in <FIG> and <FIG>, the cyclone body (container) <NUM> of the collection section <NUM> includes a container body <NUM> that internally forms a truncated conical space <NUM>, and a lid <NUM> that overs the top opening of the container body <NUM>. The liquid introduction pipe 23b of the liquid introduction section <NUM> is connected to the side of the container body <NUM> of the cyclone body <NUM>. The cyclone body <NUM> including the container body <NUM> and the lid <NUM> is a rotating body having an axis of rotation 21A, and is disposed such that the axis 21A extends in the longitudinal direction. The cyclone body <NUM> is not limited to the one having the above structure, i.e. including the container body <NUM>, and the lid <NUM> that covers the top opening of the container body <NUM>. For example, the cyclone body <NUM> may have a structure in which the container body <NUM> and the lid <NUM> are formed completely integrally and which has been obtained by using, for example, a 3D printer. In that case, the lid <NUM> of the cyclone body <NUM> constitutes an upper-end portion of the cyclone body <NUM>, and the truncated conical side wall 31b of the container body <NUM> constitutes the side wall 31b of the cyclone body <NUM>. Further, the lower-end portion 31a of the container body <NUM> constitutes the lower-end portion 31a of the cyclone body <NUM>.

The gas introduction section <NUM> is coupled to the lid <NUM> constituting the upper end of the cyclone body <NUM>, and to the gas introduction section <NUM> is connected a connection end 33b of a gas inlet <NUM> formed in the lid <NUM>. In this embodiment, four gas introduction sections <NUM> are coupled to the lid <NUM> such that each gas introduction section <NUM> extends in a direction tangent to the wall surface of the cyclone body <NUM>. The four gas introduction sections <NUM> are disposed at <NUM>-degree intervals around the circumference of the lid <NUM>. Thus, four gas inlets <NUM>, corresponding to the four gas introduction sections <NUM>, are provided at <NUM>-degree intervals in the lid <NUM>. The direction tangent to the wall surface herein refers to a direction tangent to a circle which is defined when the cyclone body <NUM> is cut off in a horizontal direction, which is perpendicular to the axis of the cyclone body <NUM>, in a portion where the gas introduced hits (collides against) the wall surface of the cyclone body <NUM>. In the case of four gas introduction sections <NUM>, the gases introduced from the four sections preferably hit (collide against) the wall surface of the cyclone body <NUM> at the same height position. Thus, the four gas introduction sections <NUM> preferably extend in directions tangent to the same circle.

An exhaust pipe 24b is mounted in the center of the lid <NUM>. The exhaust pipe 24b extends upward from the space <NUM> in the container body <NUM> and penetrates the lid <NUM>. The liquid supply section <NUM> is mounted to the lower-end portion 31a of the container body <NUM> of the cyclone body <NUM>. The liquid supply section <NUM> is connected to the droplet forming section <NUM> via the feed pump <NUM>.

The four gas inlets <NUM>, provided in the lid <NUM>, will now be described. Each gas inlet <NUM> extends in the lid <NUM> downward at an inclination angle θ of <NUM>° to <NUM>° with an orthogonal plane 21B perpendicular to the axis 21A of the cyclone body <NUM>. Each gas inlet <NUM> has an opening 33a that opens into the space <NUM> in the container body <NUM>. The opening 33a opens in the same plane as the lower surface 32a of the lid <NUM> without projecting downward from the lower surface 32a.

A liquid film <NUM>, composed of the liquid that has been introduced from the liquid introduction pipe 23b of the liquid introduction section <NUM>, is formed on the interior surface of the cyclone body <NUM>. The liquid film <NUM> is formed over an area from the lower end to the upper end of the container body <NUM>, in particular an area from the lower-end portion 31a of the container body <NUM> to a position on the side wall 31b just below the lid <NUM>. The liquid film <NUM> does not reach the lower surface 32a of the lid <NUM>.

The openings 33a of the gas inlets <NUM> provided in the lid <NUM> each open in the lower surface 32a of the lid <NUM> at a position at a distance from the side wall of the container body <NUM>. Therefore, the liquid film <NUM> on the interior surface of the container body <NUM> will not be caught in the intake gas from the openings 33a of the gas inlets <NUM>. This prevents the generation of a mist caused by the liquid film being caught in the intake gas.

On the other hand, since the gas inlets <NUM> extend downward at an angle with the orthogonal plane 21B of the cyclone body <NUM>, the intake gas ejected from each gas inlet <NUM> hits the liquid film <NUM> formed on the interior surface of the container body <NUM> and located at a position facing the opening 33a. This enables particles, contained in the intake gas, to securely adhere to the liquid film <NUM>, thus allowing the liquid film <NUM> to securely collect the particles.

If the intake gas ejected from each gas inlet <NUM> does not hit the liquid film <NUM> in the container body <NUM>, then it may not be possible to cause particles in the intake gas to adhere to the liquid film <NUM>. The particles may be forced to fly upward in the container body <NUM> and discharged from the exhaust pipe 24b.

In contrast, according to the present invention, the intake gas, ejected from each gas inlet <NUM> into the cyclone body <NUM>, is ejected along a direction tangent to the wall surface of the cyclone body <NUM> in a portion where the gas hits the liquid film, and creates a gas flow that swirls in the circumferential direction of the cyclone body <NUM>. Therefore, particles in the intake gas move toward the side wall 31b of the container body <NUM> due to centrifugal force. The particles in the intake gas ejected from the gas inlets <NUM> are thus allowed to securely hit and adhere to the liquid film <NUM>, and then can be collected.

The operation of the thus-constructed measuring apparatus according to this embodiment will now be described.

First, as shown in <FIG>, a gas (e.g. air) is drawn by the suction pump <NUM> into the main pipe <NUM> via the dust removal section <NUM>, and a gas flow is created which flows through the droplet forming section <NUM>, the droplet sorting section <NUM>, the measuring section <NUM> and the liquid recovery section <NUM> in this order, and which is discharged via the suction pump <NUM> and the not-shown filter.

On the other hand, by the operation of the suction/exhaust pump 24a of the collection section <NUM>, a gas (e.g. air) is drawn into the gas introduction sections <NUM> of the collection section <NUM> via the coarse dust removal section <NUM>, and introduced from the gas introduction sections <NUM> into the cyclone body <NUM>. Further, a liquid containing a fluorescent substance is introduced from the liquid introduction section <NUM> into the cyclone body <NUM>.

The gas, which has been introduced from the gas introduction sections <NUM> into the cyclone body <NUM>, is guided along the wall surface of the cyclone body <NUM>, so that the gas swirls in the circumferential direction and creates a spiral flow in the cyclone body <NUM>. The liquid, which has been introduced from the liquid introduction section <NUM> into the cyclone body <NUM>, is forced radially outward by the spiral gas flow and forms into a film along the wall surface of the cyclone body <NUM>.

Detection target particles contained in the gas are separated toward the wall surface of the cyclone body <NUM> due to centrifugal force, and collected in the film-shaped liquid. The fluorescent substance contained in the liquid specifically binds to the collected detection target particles.

The behavior of the gas in the cyclone body <NUM> will now be described with reference to <FIG>.

As shown in <FIG>, the intake gas, which has been introduced from the gas introduction sections <NUM>, passes through the gas inlets <NUM> provided in the lid <NUM> and is ejected from the openings 33a of the gas inlets <NUM> into the space <NUM> in the container body <NUM>.

The openings 33a of the gas inlets <NUM> are located at a distance from the side wall 31b of the container body <NUM> where the liquid film <NUM> is formed. Therefore, it is unlikely that the liquid film, formed on the interior surface of the container body <NUM>, will be caught in the intake gas, resulting in the generation of a mist.

The intake gas, ejected from the openings 33a of the gas inlets <NUM>, hits the liquid film <NUM> formed on the interior surface of the container body <NUM>. This enables particles in the intake gas to securely adhere to and be collected in the liquid film <NUM>.

The liquid in which detection target particles are collected on the wall surface of the cyclone body <NUM> gradually flows downward by gravity and, by the operation of the feed pump <NUM>, is continuously supplied from the bottom of the cyclone body <NUM> to the droplet forming section <NUM> via the liquid supply section <NUM>.

In the droplet forming section <NUM>, the liquid supplied from the collection section <NUM> is drawn from the end of the liquid supply section <NUM> by the fast gas flow flowing through the narrowed portion 18a of the main pipe <NUM>, and is formed into aerosol droplets. The aerosol droplets are carried by the gas flow in the main pipe <NUM> to the droplet sorting section <NUM>.

As shown in <FIG>, in the droplet sorting section <NUM>, the gas flow containing the droplets supplied from the droplet forming section <NUM> is guided along the cylindrical interior surface of the central chamber body 14a, whereby it swirls in the circumferential direction. Droplets having a diameter of not less than a predetermined value, contained in the gas flow, are separated toward the interior surface of the central chamber body 14a due to centrifugal force, and hit and adhere to the interior surface. On the other hand, droplets having a diameter of less than the predetermined value move upward while swirling in the circumferential direction together with the gas flow, and are supplied from the top of the upper chamber body 14b to the measuring section <NUM>.

As shown in <FIG>, the measuring section <NUM> irradiates droplets, which have been sorted out by the droplet sorting section <NUM>, with light and measures the fluorescence intensities of the irradiated droplets. In particular, the measuring section <NUM> irradiates droplets, which have been guided by the main pipe <NUM>, with light and measures the fluorescence intensities of the irradiated droplets. Thereafter, the measuring section <NUM>, for example, determines whether detection target particles are contained in the analyte gas by comparing the measured fluorescence intensities with a threshold. In other words, the measuring section <NUM> detects detection target particles in the analyte gas.

For example, in the measuring section <NUM>, the light-emitting section <NUM> emits ultraviolet laser light into the case body <NUM> through which droplets are flowing. A fluorescent substance in a droplet is excited by the ultraviolet laser light and emits fluorescence. The ultraviolet laser light is then blocked by the optical filter <NUM>, and light having a fluorescence wavelength is selectively detected by the light-receiving section <NUM>. The intensity of received light, detected by the light-receiving section <NUM>, is proportional to the volume density of the fluorescent substance in a droplet formed by the droplet forming section <NUM>.

In the case where detection target particles are present in droplets formed by the droplet forming section <NUM>, the fluorescence intensities detected by the light-receiving section <NUM> are higher than the threshold Is, and the received-light output measuring section <NUM> issues an alarm indicating detection of detection target particles.

In the case where no detection target particles are present in droplets formed by the droplet forming section <NUM>, even when fine dust in the air is incorporated into the droplets and the fluorescent substance adheres to the dust, the density of the fluorescent substance is much lower than the density of the fluorescent substance bonded to detection target particles. Accordingly, the intensity of received light detected by the light-receiving section <NUM> is lower than the preset threshold Is.

The gas flow containing droplets, which has passed through the measuring section <NUM>, is separated into the gas and the liquid, and the liquid is recovered. The gas, on the other hand, is discharged to the outside of the measuring apparatus <NUM> by the suction pump <NUM> provided downstream of the liquid recovery section <NUM>.

A collection section <NUM> consisting of a cyclone collector according to a second embodiment will now be described with reference to <FIG>.

In the second embodiment shown in <FIG>, the same symbols are used for the same components or elements as those of the first embodiment shown in <FIG>, <FIG>, and <FIG>, and a detailed description thereof is omitted.

<FIG> is a side view of the cyclone body <NUM> of the collection section <NUM>, <FIG> is a bottom view of a lid as viewed from line A-A' of <FIG> is a cross-sectional view on line B-B' of <FIG>, showing the cyclone body <NUM>.

As described above, the collection section <NUM> includes a cyclone body (also referred to as a container) <NUM>, a gas introduction section <NUM> for introducing a gas into the cyclone body <NUM>, and a liquid introduction section (also referred to as a liquid-film forming section) <NUM> for introducing a liquid into the cyclone body <NUM> and forming a liquid film <NUM> on the interior surface of the cyclone body <NUM>.

More specifically, as shown in <FIG>, the cyclone body (container) <NUM> of the collection section <NUM> includes a container body <NUM> that internally forms a truncated conical space <NUM>, and a lid <NUM> that overs the top opening of the container body <NUM>. The liquid introduction pipe 23b of the liquid introduction section <NUM> is connected to the side of the container body <NUM> of the cyclone body <NUM>.

The gas introduction section <NUM> is coupled to the lid <NUM> of the cyclone body <NUM>, and to the gas introduction section <NUM> is connected a connection end 33b of a gas inlet <NUM> formed in the lid <NUM>. In this embodiment, eight gas introduction sections <NUM> are coupled to the lid <NUM> such that each gas introduction section <NUM> extends in a direction tangent to the wall surface of the cyclone body <NUM>. The eight gas introduction sections <NUM> are disposed at <NUM>-degree intervals around the circumference of the lid <NUM>. Thus, eight gas inlets <NUM>, corresponding to the eight gas introduction sections <NUM>, are provided at <NUM>-degree intervals in the lid <NUM>.

An exhaust pipe 24b is mounted in the lid <NUM>. The exhaust pipe 24b extends upward from the space <NUM> in the container body <NUM> and penetrates the lid <NUM>.

The eight gas inlets <NUM>, provided in the lid <NUM>, will now be described. Each gas inlet <NUM> extends in the lid <NUM> downward at an inclination angle θ of <NUM>° to <NUM>° with an orthogonal plane 21B perpendicular to the axis 21A of the cyclone body <NUM>. Each gas inlet <NUM> has an opening 33a that opens into the space <NUM> in the container body <NUM>. The opening 33a opens in the same plane as the lower surface 32a of the lid <NUM> without projecting downward from the lower surface 32a.

The openings 33a of the gas inlets <NUM> provided in the lid <NUM> each open in the lower surface 32a of the lid <NUM> at a position at a distance from the interior surface of the container body <NUM>. Therefore, the liquid film <NUM> on the interior surface of the container body <NUM> will not be caught in the intake gas from the openings 33a of the gas inlets <NUM>. This prevents the generation of a mist caused by the liquid film being caught in the intake gas.

On the other hand, since the gas inlets <NUM> extend downward at an angle with the orthogonal plane 21B of the cyclone body <NUM>, the intake gas ejected from each gas inlet <NUM> hits the liquid film <NUM> formed on the interior surface of the container body <NUM> and located at a position facing the opening 33a. This enables particles, contained in the intake gas, to securely adhere to the liquid film <NUM>, thus allowing the liquid film <NUM> to securely capture the particles.

In contrast, according to the present invention, the intake gas ejected from the gas inlets <NUM> is allowed to hit the liquid film <NUM>. This makes it possible to cause particles in the intake gas to adhere to the liquid film <NUM>, and to securely collect the particles in the liquid. According to this embodiment, the number of the gas inlets <NUM> is increased by increasing the angle θ of each gas inlet <NUM>. This can increase the amount of gas that can be treated at a time. However, the gas flow hits the wall surface at a lower position.

A collection section <NUM> consisting of a cyclone collector according to a third embodiment will now be described with reference to <FIG>.

In the third embodiment shown in <FIG>, the same symbols are used for the same components or elements as those of the first embodiment shown in <FIG>, <FIG>, and <FIG>, and a detailed description thereof is omitted.

The gas introduction section <NUM> is coupled to the lid <NUM> of the cyclone body <NUM>, and to the gas introduction section <NUM> is connected a connection end 33b of a gas inlet <NUM> formed in the lid <NUM>. In this embodiment, a single gas introduction section <NUM> is coupled to the lid <NUM>. However, it is also possible to provide a plurality of gas introduction section <NUM>, gas inlets <NUM> and projecting nozzles <NUM>.

The gas inlet <NUM>, provided in the lid <NUM>, will now be described. The gas inlet <NUM> extends in the lid <NUM> downward at an inclination angle θ of <NUM>° to <NUM>° with an orthogonal plane 21B perpendicular to the axis 21A of the cyclone body <NUM>. The gas inlet <NUM> has a projecting nozzle <NUM> which projects from the lower surface 32a of the lid <NUM> into the space <NUM> in the container body <NUM> and which opens at the lower end, forming an opening 33a. Thus, the opening 33a is located at the lower end of the projecting nozzle <NUM> projecting downward from the lower surface 32a of the lid <NUM>.

A liquid film <NUM>, composed of the liquid that has been introduced from the liquid introduction pipe 23b of the liquid introduction section <NUM>, is formed on the interior surface of the cyclone body <NUM>. The liquid film <NUM> is formed over an area from the lower end to the upper end of the container body <NUM>, i.e. an area from the lower end of the container body <NUM> to the lower surface 32a of the lid <NUM>.

The opening 33a of the gas inlet <NUM> provided in the lid <NUM> is located at the lower end of the projecting nozzle <NUM> projecting from the lower surface 32a of the lid <NUM>, and opens at a position at a distance from the interior surface of the container body <NUM>. Therefore, the liquid film <NUM> on the interior surface of the container body <NUM> will not be caught in the intake gas from the opening 33a of the gas inlet <NUM>. This prevents the generation of a mist caused by the liquid film being caught in the intake gas.

On the other hand, since the gas inlet <NUM> extends downward at an angle with the orthogonal plane 21B of the cyclone body <NUM>, the intake gas ejected from the gas inlet <NUM> hits the liquid film <NUM> formed on the interior surface of the container body <NUM> and located at a position facing the opening 33a. This enables particles, contained in the intake gas, to securely adhere to the liquid film <NUM>, thus allowing the liquid film <NUM> to securely capture the particles.

If the intake gas ejected from the gas inlet <NUM> does not hit the liquid film <NUM> in the container body <NUM>, then it may not be possible to cause particles in the intake gas to adhere to the liquid film <NUM>. The particles may be forced to fly upward in the container body <NUM> and discharged from the exhaust pipe 24b.

In contrast, according to the present invention, the intake gas ejected from the gas inlet <NUM> is allowed to hit the liquid film <NUM>. This makes it possible to cause particles in the intake gas to adhere to the liquid film <NUM>, and to securely collect the particles in the liquid.

A collection section <NUM> consisting of a cyclone collector according to a fourth embodiment will now be described with reference to <FIG>.

In the fourth embodiment shown in <FIG>, the same symbols are used for the same components or elements as those of the first embodiment shown in <FIG>, <FIG>, and <FIG>, and a detailed description thereof is omitted.

<FIG> is a side view of the cyclone body <NUM> of the collection section <NUM>.

More specifically, as shown in <FIG>, the cyclone body (container) <NUM> of the collection section <NUM> includes a container body <NUM> which internally forms a truncated conical space <NUM> and which consist of a revolution body having an axis of rotation 21A. The conical body <NUM> is hermetically sealed as a whole and includes a lower-end portion 31a, an upper-end portion 31c and a side wall 31b extending between the lower-end portion 31a and the top-end portion 31c. The liquid introduction pipe 23b of the liquid introduction section <NUM> is connected to the side wall 31b.

The gas introduction section <NUM> is coupled to the upper-end portion 31c of the container body <NUM> of the cyclone body <NUM>, and to the gas introduction section <NUM> is connected a connection end 33b of a gas inlet <NUM> formed in the upper-end portion 31c. In this embodiment, four gas introduction sections <NUM> are coupled to the upper-end portion 31c such that each gas introduction section <NUM> extends in a direction tangent to the wall surface of the cyclone body <NUM>. The four gas introduction sections <NUM> are disposed at <NUM>-degree intervals around the circumference of the upper-end portion 31c. Thus, four gas inlets <NUM>, corresponding to the four gas introduction sections <NUM>, are provided at <NUM>-degree intervals in the upper-end portion 31c.

An exhaust pipe 24b is mounted in the center of the upper-end portion 31c. The exhaust pipe 24b extends upward from the space <NUM> in the container body <NUM> and penetrates the upper-end portion 31c. The liquid supply section <NUM> is mounted to the side wall 31b of the container body <NUM> of the cyclone body <NUM>. The liquid supply section <NUM> is connected to the droplet forming section <NUM> via the feed pump <NUM> (see <FIG>). An inlet 26a, which is inversely tapered toward the space <NUM>, is formed at the entrance to the liquid supply section <NUM> mounted to the side wall 31b. Since the liquid supply section <NUM> is mounted to the side wall 31b in this embodiment, the liquid, which has a higher specific gravity than air, can be smoothly brought by centrifugal force from the inversely tapered inlet 26a to the liquid supply section <NUM>.

The four gas inlets <NUM>, provided in the upper-end portion 31c of the container body <NUM>, will now be described. Each gas inlet <NUM> extends in the upper-end portion 31c downward at an inclination angle θ of <NUM>° to <NUM>° with an orthogonal plane 21B perpendicular to the axis 21A of the cyclone body <NUM>. Each gas inlet <NUM> has an opening 33a that opens into the space <NUM> in the container body <NUM>. The opening 33a opens in the same plane as the lower surface 31c1 of the upper-end portion 31c without projecting downward from the lower surface 31c1.

A liquid film <NUM>, composed of the liquid that has been introduced from the liquid introduction pipe 23b of the liquid introduction section <NUM>, is formed on the interior surface of the side wall 31b of the cyclone body <NUM>. The liquid film <NUM> is formed over an area from the lower end to the upper end of the side wall 31b of the container body <NUM>. However, the liquid film <NUM> does not reach the lower surface 31c1 of the upper-end portion 31c.

The openings 33a of the gas inlets <NUM> provided in the upper-end portion 31c of the container body <NUM> each open in the lower surface 31c1 of the upper-end portion 31c at a position at a distance from the side wall 31b of the container body <NUM>. Therefore, the liquid film <NUM> on the interior surface of the side wall 31b of the container body <NUM> will not be caught in the intake gas from the openings 33a of the gas inlets <NUM>. This prevents the generation of a mist caused by the liquid film being caught in the intake gas.

On the other hand, since the gas inlets <NUM> extend obliquely downward with respect to the orthogonal plane 21B of the cyclone body <NUM>, the intake gas ejected from each gas inlet <NUM> hits the liquid film <NUM> formed on the interior surface of the side wall 31b of the container body <NUM> and located at a position facing the opening 33a. Therefore, particles contained in the intake gas move to the liquid film <NUM> due to centrifugal force. This enables the particles to securely adhere to the liquid film <NUM>, thus allowing the liquid film <NUM> to securely collect the particles.

If the intake gas ejected from each gas inlet <NUM> does not hit the liquid film <NUM> on the interior surface of the side wall 31b of the container body <NUM>, then it may not be possible to cause particles in the intake gas to adhere to the liquid film <NUM>. The particles may be forced to fly upward in the container body <NUM> and discharged from the exhaust pipe 24b.

In contrast, according to the present invention, the intake gas ejected from the gas inlets <NUM> is allowed to hit the liquid film <NUM>. This makes it possible to cause particles in the intake gas to adhere to the liquid film <NUM>, and to securely collect the particles in the liquid. The cyclone body <NUM> shown in <FIG> may be used in a vertically inverted shape: the upper-end portion 31c and the lower-end portion 31a are interchanged, and the gas introduction sections <NUM> and the exhaust pipe 24b are disposed at lower positions.

A collection section <NUM> consisting of a cyclone collector according to a fifth embodiment will now be described with reference to <FIG>.

In the fifth embodiment shown in <FIG>, the same symbols are used for the same components or elements as those of the first embodiment shown in <FIG>, <FIG>, and <FIG>, and a detailed description thereof is omitted.

An exhaust pipe 24b is mounted in the center of the lower-end portion 31a. The exhaust pipe 24b extends downward from the space <NUM> in the container body <NUM> and penetrates the lower-end portion 31a. Since the exhaust pipe 24b is mounted in the center of the lower-end portion 31a, the exhaust pipe 24b is located opposite the gas introduction sections <NUM> in the upper-end portion 31c. This can increase the degree of freedom of the installation position of the gas introduction sections <NUM> in the upper-end portion 31c. The liquid supply section <NUM> is mounted to the side wall 31b of the container body <NUM> of the cyclone body <NUM>. The liquid supply section <NUM> is connected to the droplet forming section <NUM> via the feed pump <NUM> (see <FIG>). An inlet 26a, which is inversely tapered toward the space <NUM>, is formed at the entrance to the liquid supply section <NUM> mounted to the side wall 31b. Since the liquid supply section <NUM> is mounted to the side wall 31b in this embodiment, the liquid having a high specific gravity can be smoothly brought by centrifugal force from the inversely tapered inlet 26a to the liquid supply section <NUM>.

Claim 1:
A cyclone collector for collecting particles in an intake gas, comprising:
a container which internally forms a space (<NUM>) and which consists of a revolution body having an axis (21A) of rotation, and including an upper-end portion (31c), a lower-end portion (31a), and a side wall (31b) extending between the upper-end portion (31c) and the lower-end portion (31a);
a liquid-film forming section (<NUM>), provided for the container, and being configured to form a liquid film (<NUM>) having a certain height on an interior surface of the side wall (31b),
a gas inlet (<NUM>) provided in the container and having an opening (33a) that opens in the container; and
an exhaust pipe provided in the container,
wherein the gas inlet (<NUM>) extends toward the space (<NUM>) at an angle with an orthogonal plane (21B) perpendicular to the axis (21A) of rotation of the container,
characterized in that
the entire area of the opening (33a) of the gas inlet (<NUM>) is located outside an area where the liquid film (<NUM>) exists, and the intake gas is ejected from the gas inlet (<NUM>) toward the liquid film (<NUM>).