JP2006218380A - Powder-scattering exposure apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide powder-scattering exposure, which has a uniform distribution of powder concentration that enables to conduct a powder-scattering exposure test with high reliability in test chambers with various sizes, whereby a subject is not exposed to unnatural wind. <P>SOLUTION: The powder-scattering exposure apparatus provided herein comprises a chamber capable of blocking powder from coming in and going out, a powder-mixed air supply means for supplying air (powder-mixed air) that contains powders mixed therein to the chamber, and a powder-scattering means for scattering powders within the chamber by blowing with rounding movement the powder-mixed air supplied from the powder-mixed air supply means in the chamber. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a device for a clinical test in which powder is scattered in a chamber (test room) to perform a powder scattering exposure test, and more particularly to a device for performing a scattering exposure test on pollen.

Various pollutants and other powders are suspended in the atmosphere and have a negative effect on the human body. In recent years, in particular, a large amount of pollen typified by cedar pollen has floated in the atmosphere, and so-called pollen allergy causing allergic symptoms has become a problem.
In order to solve this problem of hay fever, there is an urgent need to develop protective devices such as masks that prevent people from inhaling pollen, as well as pharmaceuticals and health foods that are effective in the symptoms of hay fever. It has become.

  In order to develop these protective devices, pharmaceuticals, and health foods, it is necessary to keep the subject in a space with a predetermined pollen concentration and to provide an environment that allows exposure to pollen that is scattered for a certain period of time. is there. However, since the true specific gravity of pollen is large and the wind speed and direction of the atmosphere change in nature, it is difficult to maintain an environment where a pollen scattering exposure test having a predetermined pollen concentration is possible for a certain period of time.

As a method for creating an environment that allows a pollen scattering exposure test having a predetermined pollen concentration, for example, a method of providing an environment having a predetermined pollen concentration by pouring pollen from the top of a chamber that is small enough for one person to put in is proposed. Has been. Moreover, as a method of providing an environment in which a pollen scattering exposure test for exposing a plurality of humans at the same time can be performed, a method has been proposed in which pollen is scattered to an area where the subject gathers by turning a plurality of blowers from the front of the subject.
Furthermore, various apparatuses have been proposed for apparatuses for spraying powders such as pollen. (For example, refer to Patent Document 1.)
JP 2000-055711 A

  However, in the method using a chamber that can be accommodated by only one person, a plurality of persons cannot be exposed at the same time, so that reliable test data cannot be obtained. Moreover, since the pollen concentration distribution in the chamber is not uniform only by increasing the size of the chamber, the amount of pollen exposure varies depending on the location, and it is difficult to obtain reliable test data.

  In addition, in the method in which pollen is scattered to the area where the subject gathers by turning the blower, multiple subjects can be exposed at the same time. Has a very different environment setting, and there is a problem that appropriate test data cannot be obtained.

  Furthermore, the powder supply apparatus described in Patent Document 1 is an invention for solving the problem of eliminating powder clogging in the apparatus to the end, and with this apparatus, a uniform powder concentration distribution can be obtained. I can't get it.

  Accordingly, an object of the present invention is to solve the above-mentioned problems and to have a uniform powder concentration distribution that enables a reliable powder scattering exposure test in various sizes of test chambers. In addition, it is an object of the present invention to provide a powder scattering exposure that does not cause an unnatural wind to hit a subject.

  In order to solve the above-described problem, a first embodiment of the powder scattering exposure apparatus of the present invention includes a chamber capable of blocking powder in / out, and a gas (powder mixture) containing powder in the chamber. A powder mixture supply means for supplying to the powder, and a powder for causing the powder mixture supplied by the powder mixture supply means to flow in the chamber so as to be swirled in the chamber. Body scattering means.

  Here, the “powder” includes a certain powder substance such as pollen, dust, and metal powder, and includes powders having any specific gravity and any particle size. The “gas” includes all gases including air, and the concentration of the powder contained in the “powder mixture” includes all concentrations.

  The “chamber” has a space inside which is partitioned from the outside by an outer shell, and has a structure capable of blocking the entry and exit of powder between this space and the outside. The shape of the chamber includes any shape including box, cylinder, cone, pyramid, sphere, or combinations thereof. However, considering the test data so far, in order to obtain a uniform powder concentration distribution, it is better to have a circular or hexagonal regular polygonal cross-sectional shape than a rectangular cross-sectional shape. It is advantageous.

  The size of the chamber includes, for example, a chamber of any size from a size suitable for accommodating small animals to a size capable of accommodating a large number of people. As the material of the outer shell, any material including metal, wood and resin can be used.

  The “powder mixture supply means” includes any device or mechanism that supplies gas containing powder. For example, it is conceivable that a powder is contained in the gas by generating a suction force, or the powder may be contained by blowing the powder into the gas. Moreover, when the gas containing powder is stored in the container etc., it can also be considered that the stored gas is supplied by blowing air to the container with a blower or the like.

  The “powder scattering means” includes all devices and mechanisms as long as the powder mixture can be swirled in the chamber. Considering the specific gravity of the powder, it is conceivable that the powder mixture swirling in the chamber gradually descends due to gravity. In addition to swirling the powder mixture, the powder mixture It is also conceivable to apply upward or downward airflow to

  According to this embodiment, by rotating the powder mixture in the chamber, the powder can be scattered in the entire region in the chamber, and a uniform concentration distribution of the powder can be formed in the chamber.

  In another embodiment of the powder scattering exposure apparatus of the present invention, the powder scattering means has at least one blowing for blowing the powder mixture in an annular channel and a tangential direction of the annular channel. And a first swirling flow generator having a mouth.

  According to this embodiment, the swirl flow can be reliably generated by blowing the powder mixture in the tangential direction of the annular channel. For example, an arbitrary number of air inlets can be provided in accordance with the air flow rate and the size of the annular channel. In addition, the number of the first swirling flow generators can be set according to the size and shape of the chamber.

  In another embodiment of the powder scattering exposure apparatus according to the present invention, the powder scattering means has at least one outlet for blowing air in a tangential direction of the swirling flow by the first swirling flow generating device. The swirl flow generator is included.

  The swirl flow of the powder mixture generated by the first swirl flow generator is thought to gradually decrease in flow velocity, but in the tangential direction of the swirl flow using the second swirl flow generator of this embodiment. By blowing, it is possible to compensate or restore the reduced swirl flow velocity. Further, the flow velocity of the swirling flow can be further increased depending on the strength of the air blow of the second swirling flow generating device.

  The blowing by the second swirling flow generator can take in an external gas and blow it into the swirling flow in the chamber, or increase the flow velocity of the swirling flow in the chamber as an internal blower installed in the chamber. Is also possible. The number of outlets can be set to an arbitrary number of outlets according to the shape of the chamber, the size of the chamber, the strength of air blowing, and the like.

  In another embodiment of the powder scattering exposure apparatus according to the present invention, the first swirl flow generator is installed in an upper portion of the chamber, and the second swirl flow generator is the first swirl flow generator. It is installed below the installation position.

  According to the present embodiment, the powder mixture is gradually lowered while swirling by the first swirling flow generating device installed at the upper portion of the chamber, and the swirling flow velocity is lowered as it is lowered. However, a swirl force is again applied to the powder mixture by the second swirl flow generator installed below the first swirl flow generator, and the powder can be scattered throughout the chamber.

  In another embodiment of the powder scattering exposure apparatus of the present invention, the second swirl flow generator is installed above the position where the subject sucks the powder mixed gas in the chamber. And

  Here, the “subject” means a person who stays in the chamber and undergoes a powder scattering exposure test, and the number of persons can be set to any number according to the purpose and purpose of the test. The subject may be, for example, a test animal. In addition, the subject undergoes a powder scattering exposure test on the floor surface of the chamber. Specifically, the subject stands on the floor surface, sits on the floor surface, sits on a chair placed on the floor surface, etc. Conceivable.

  In the present embodiment, since the second swirl flow generator is installed above the position where the subject sucks the powder mixture, the powder mixture to which the swirl force is given by the second swirl flow generator Qi can be set so that the swirl velocity decreases as it descends, and the flow velocity becomes very low at the position where the subject sucks in the powder mixed gas. Therefore, according to this embodiment, not only a uniform powder concentration distribution can be obtained in the chamber, but also a test environment similar to that when a person inhales powder in nature can be set.

  Another embodiment of the powder scattering exposure apparatus of the present invention is characterized in that air conditioning in the chamber can be further performed by the second swirl flow generator.

  According to this embodiment, the second swirling flow generating device also functions as air conditioning, and the temperature and humidity in the chamber can be controlled to desired values. Therefore, it is possible to set up an environment where subjects can take a powder scattering exposure test for a long time, and it is also possible to conduct a powder scattering exposure test that simulates various natural conditions and environments. is there.

  Another embodiment of the powder scattering exposure apparatus of the present invention is characterized in that the cross-sectional shape of the chamber is a circle or a regular polygon having 6 or more corners. According to this embodiment, a uniform powder concentration distribution can be formed in the chamber.

In another embodiment of the powder scattering exposure apparatus of the present invention, the powder mixture supply means is in the air blown by the blower with the compressed air containing the powder sucked using the negative pressure due to the gas flow. The powder mixture having a predetermined powder concentration is supplied by being blown into the container.
According to this embodiment, a powder mixture in which powder is uniformly mixed in a gas can be created and supplied to the chamber.

  Another embodiment of the powder scattering exposure apparatus of the present invention is characterized in that the powder is pollen.

According to the powder scattering exposure apparatus of the present invention, a powder scattering exposure test having a uniform powder concentration distribution in a chamber of any size can be performed by swirling the powder mixture in the chamber. You can get the environment.
Furthermore, at the position where the subject inhales the powder, the flow rate of the powder mixture can be reduced to obtain an environment for the powder scattering exposure test that is close to the natural environment.

  Embodiments of the powder scattering exposure apparatus of the present invention will be described below in detail with reference to the drawings.

(Explanation of general equipment)
In FIG. 1, the external view of one embodiment of the powder scattering exposure apparatus of this invention is shown. In this embodiment, a case where (cedar) pollen is scattered as powder in a chamber (test room) will be described as an example. FIG. 1A shows a plan view of the outer shape of the apparatus viewed from above, and FIG. 1B shows a side view. FIG. 2 shows a cross-sectional view as seen from the arrow A in FIG.

  The powder scattering exposure apparatus of the present invention includes a chamber 2, a powder mixture supply means 3 for supplying air containing pollen to the chamber 2, and air containing pollen supplied by the powder mixture supply means 3. And a powder scattering means 4 for causing pollen to flow into the chamber.

In this embodiment, the chamber 2 has a regular octagonal cross-sectional shape (floor shape) with an inscribed circle diameter of 6 m, and the height of the chamber 2 is about 4.2 m. Further, the roof portion of the chamber 2 has an octagonal truncated pyramid shape and is narrowed toward the top.
Further, as ancillary equipment of the chamber 2, a front room 2 a and an air shower room 2 b that pass through before the subject enters the chamber 2 are connected to the chamber 2.

The powder mixture supply means 3 includes a compressed air generator 10 that generates compressed air, a powder mixture generator 20 that generates pollen by adding pollen to the generated compressed air, a pipe 25, and a branch. The pollen mixture sent through the pipes 25a and 25b and the air blown by the blowers 32a and 32b are mixed, and the pipes 34a and 34b are sent to the first swirl flow generator 40 installed in the upper part of the chamber 2. A powder mixture feeding mechanism 30 to be fed.
The powder mixture feeding mechanism 30 mixes the pollen mixture sent from the branch pipe 25a and the air blown by the blower 32a, and sends the mixture from the pipe 34a to the blowing port 40a of the first swirling flow generating device 40. The first turning mechanism 30a (the mechanism on the right side in FIG. 1 (b)), the pollen mixture sent from the branch pipe 25b, and the air blown by the blower 32b are mixed, and the first turning is made from the pipe 34b. And a second feeding mechanism 30b (the left-side mechanism in FIG. 1B) that feeds into the blowing port 40b of the flow generating device 40.

  In addition, as shown in FIG. 1B, in this embodiment, the compressed air generator 10 and the powder mixture generator 20 are installed on the ground, and each device constituting the powder mixture feeding mechanism 30 is , Installed on the roof of the chamber 2. However, the arrangement of these devices can be arbitrarily arranged according to the situation.

  The powder scattering means 4 includes a first swirling flow generating device 40 installed at the upper part of the chamber 2 and a second swirling flow generating device 42 installed below the first swirling flow generating device 40. . The first swirling flow generating device 40 blows the pollen mixture fed by the powder mixture feeding mechanism 30 so as to flow in an arc shape in the chamber 2 as shown by the arrow in FIG. . As shown in FIG. 2, the second swirl flow generating device 42 applies a swirl force by adding an air flow in the tangential direction of the pollen mixture descending while swirling by the action of the first swirl flow generating device 40. Work.

  In the present embodiment, the first swirl flow generator 40 is installed at a height of about 4.2 m from the floor of the chamber 2, and the second swirl flow generator 42 is at a height of about 2 m from the floor of the chamber 2. is set up. In addition, an air conditioner is used as the second swirl flow generator 42 so that air conditioning (temperature and humidity control) in the chamber 2 can be performed. The subject who undergoes the powder scattering exposure test is designed to suck the powder mixture at a height of 70 cm to 1 m from the floor of the chamber.

  Further, as shown in FIG. 2, the present embodiment further includes an intake device 50 and an exhaust device 52 that ventilate the chamber 2. The second swirl flow generating device 42, the intake device 50, and the exhaust device 52 described above are provided with filters, and external impurities are mixed into the chamber 2 or pollen in the chamber 2 leaks to the outside. To prevent you from doing. The intake device 50 and the exhaust device 52 are designed to ventilate at a very low flow rate so as not to disturb the flow of the pollen mixture.

(Explanation of gas flow)
Next, the flow of gas will be described with reference to FIGS. 1 and 2. The arrow shown in the piping part of a figure shows the flow of gas.
First, compressed air is generated by the compressed air generator 10. As will be described later, the compressed air generator 10 includes a compressor and a dryer, and can generate dry compressed air. Furthermore, a flow rate control valve is provided to control the flow rate to a desired level.

  This compressed air enters the powder mixture generator 20 through the pipe 14. In the powder mixture generator 20, pollen stored in the powder storage chamber can be sucked into the compressed air and contained by using the principle of an ejector as will be described later.

The pollen mixture generated by the powder mixture generator 20 rises through the pipe 25, branches into the branch pipe 25 a and the branch pipe 25 b, and is connected to the powder mixture feeding mechanism 30. The powder mixture feeding mechanism 30 includes a first feeding mechanism 30a composed of a blower 32a and a pipe 34a, and a second feeding mechanism 30b composed of a blower 32b and a pipe 34b.
As shown in FIGS. 1A and 1B, the branch pipe 25a is connected to the pipe 34a, and the branch pipe 25b is connected to the pipe 34b, but the branch pipe 25a and the branch pipe 25b indicate the position of the pipe 25. It has a substantially symmetrical shape as the center line, and is arranged so that the pollen mixture flows equally between the branch pipe 25a and the branch pipe 25b.

  The pollen mixture flowing from the branch pipe 25a is blown into the air blown by the blower 32a at the connection point 34c with the pipe 34a, and the pollen concentration becomes uniform while the mixture flows through the pipe 34a. To the inlet 40a of the swirling flow generator 40. Similarly, the pollen mixture flowing from the branch pipe 25b is blown into the air blown by the blower 32b at the connection point 34d with the pipe 34b, and the pollen concentration becomes uniform while the mixture flows through the pipe 34b. And reaches the inlet 40b of the first swirl flow generator 40.

  The positions of the connection points 34c, d are in the vicinity of the connection positions of the pipes 34a, b with the blowers 32a, b, but a certain straight pipe portion is secured between the connection points 34c, d and the blowers 32a, b. Has been. Between the connection points 34c, d and the outlets 40a, 40b of the first swirling flow generator 40, secure a straight pipe portion with a sufficient distance for the pollen concentration in the pollen mixture to be uniform. It is.

In the first swirling flow generating device 40 having an annular flow path, as shown by the arrow in FIG. 1A, the pollen mixture fed by the branch pipe 25a flows from the blowing port 40a to the annular flow path. Similarly, the pollen mixture sent by the branch pipe 25b is blown in the tangential direction of the annular channel from the blowing port 40b.
Therefore, the pollen mixture flows so as to swirl in the annular flow path of the first swirl flow generator 40. The pollen mixture descends due to gravity while swirling in the chamber 2. At this time, the pollen mixture descends while the swirling diameter increases along the shape of the roof of the chamber 2.

In addition, at a height of about 2 m from the floor of the chamber 2, the air outlet 42 a and the air outlet 42 b of the second swirl flow generator are installed on two opposing surfaces of the chamber 2 having a regular octagonal cross section. As shown by the white arrows in FIG. 2, a turning force is applied by adding an air flow in the turning direction of the pollen mixture that descends while turning.
As described above, the swirling flow of the pollen mixture in the chamber 2 enables the pollen to be uniformly scattered in the chamber 2, and a uniform pollen concentration distribution can be obtained in the chamber 2.

  The pollen contained in the pollen mixture is finally deposited on the floor surface of the chamber 2, but when the pollen concentration is measured with a measuring device, the powder scattering exposure test in which the subject is basically stationary. In, there is no risk of pollen rising on the floor. A more detailed description of the flow of the pollen mixture in the chamber 2 will be described later.

In the present embodiment, by using an air conditioner as the second swirl flow generator 42, the temperature and humidity of the air in the chamber 2 can be controlled to desired values. Furthermore, in order to ventilate the inside of the chamber 2, an intake device 50 that takes in outside air and an exhaust device 52 that discharges internal air to the outside are provided. The second swirl flow generator 42, the intake device 50, and the exhaust device 52 are provided with filters, and external impurities are mixed in the chamber 2 or pollen in the chamber 2 leaks to the outside. It prevents that. In addition, ventilation is set at a very low flow rate so as not to disturb the flow of the pollen mixture.
Next, a detailed description will be given of the main components of the powder scattering exposure apparatus of the present invention.

(Explanation of chamber 2)
In this embodiment, the chamber 2 has a regular octagonal floor shape in which a circle having a diameter of 6 m is inscribed. As the floor shape of the chamber 2, a regular octagon is employed in the present embodiment, but other regular polygonal or circular floor shapes can be employed. However, considering a uniform pollen distribution, a regular polygon or a circle with as many angles as possible is desirable.
From each side of the regular octagonal floor of the chamber 2, a flat side wall extends vertically to a height of 2.5 m, and a roof portion having an octagonal pyramid shape is connected thereto. The height of the top of the roof portion is about 4.2 m from the floor of the chamber 2.

A chair on which a subject sits can be installed in the chamber 2, and a pollen exposure test for a long time can be performed in the chamber 2. In this chamber 2, 30 subjects can be accommodated. Moreover, in order to measure the pollen density | concentration in the chamber 2, a measuring apparatus can be installed in arbitrary places. As an apparatus for measuring pollen, an automatic measuring apparatus that continuously measures pollen concentration and displays it on a screen can be installed.
The pollen contained in the pollen mixture is finally deposited on the floor surface of the chamber 2, but in the above measurement and test, the problem that the pollen deposited on the floor rises does not occur. However, pollen re-scattering can be more effectively prevented by pulling a carpet or the like on the floor.

  As ancillary equipment of the chamber 2, a front room 2 a and an air shower room 2 b that pass before the subject enters the chamber 2 are connected to the chamber 2. Each room is provided with a door to prevent impurities from entering the chamber 2 and pollen in the chamber 2 from flowing out to the outside when the subject enters the chamber 2. In addition, the air shower chamber 2b can remove impurities attached to the body of the subject by blowing air from above to the subject with the blower 54.

  When the subject enters the chamber 2, first, the door of the front chamber 2a is opened and the front chamber 2a is entered. At this time, the door of the air shower chamber 2b is in a closed state. Next, the door of the front chamber 2a is closed, the door of the air shower chamber 2b is opened, and the air shower chamber 2b is entered. At this time, the door of the chamber 2 is in a closed state. Next, the door of the air shower room 2b is closed, the door of the chamber 2 is opened to enter the chamber 2, and the door of the chamber 2 is closed. At this time, in the air shower chamber 2b, impurities such as dust attached to the subject are removed by the air shower (air flow from above).

(Description of powder mixture supply means 3)
Next, each component of the powder mixture supply means 3 including the compressed air generator 10, the powder mixture generator 20, and the powder mixture feeding mechanism 30 will be described.

<Description of Compressed Air Generator 10>
First, the compressed air generator 10 will be described with reference to FIG. 3A schematically showing each device. The compressed air generator 10 includes a compressor 11, a dryer 12, and a flow rate control valve 13. Compressed air having a desired pressure is generated by the compressor 11. Further, since moisture in the air condenses during the compression process of the compressor 11, the moisture in the compressed air is removed by the dryer 12. Then, the flow rate is adjusted to a desired flow rate by the flow rate adjusting valve 13, and the compressed air is sent to the powder mixture generating apparatus 20 by the pipe 14.

<Description of Powder Mixture Generator 20>
Next, the powder mixture generator 20 will be described with reference to FIGS. 3A and 3B schematically showing each device. The powder mixture generator 20 includes a disk 21 in which grooves are formed in an arc shape, a drive device 22 that rotates the disk 21, and a rotating disk 21 that rotates stored pollen from a lower spout 23a. The pollen storage chamber 23 poured into the groove portion, the ejector 24 for sucking the pollen in the disk 21 (in the groove) using the negative pressure generated when the compressed air is blown, and excess pollen on the disk 21 are removed. And a scraper 26.

FIG. 3B is a diagram showing a detailed structure of a portion indicated by an arrow C in FIG. 3A, and shows a detailed cross-sectional shape of each recess 21 a constituting the arc-shaped groove of the disk 21. A plurality of concave portions 21 a having the same shape and the same dimensions are arranged in the circular shape in the disc 21, and a groove portion of the disc 21 is formed. As shown in FIG.3 (b), the cross-sectional shape of each recessed part 21a has a substantially U shape.
The lower part of the pollen storage chamber 23 for storing pollen has a funnel shape, and a spout 23a is opened at the lower end. As shown to Fig.3 (a), the pollen stored in the pollen storage chamber 23 is poured into the rotating disc 21 from the spout 23a. At this time, pollen is filled in each recess 21a, and at the same time, surplus pollen accumulates on the disc 21.

  As shown in FIG. 3A, when the disk 21 rotates, each recess 21a passes under the scraper 26, and at this time, excess pollen deposited on the disk 21 is removed by the scraper 26. Removed. The function of the scraper 26 is shown in FIG. The region indicated by X shows the state before the excess pollen passes through the scraper 26 accumulated on the disk 21, and the region indicated by Y is removed by the scraper 26, and the pollen is only in the recess 21a. Indicates a filled state.

  As the disk 21 rotates, the recess 21 a that has passed through the scraper 26 reaches the position of the ejector 24. In the ejector 24, as shown in FIG. 3A, compressed air is blown upward from the pipe 14 into the ejector 24 on the paper surface. At this time, in the ejector 24, a negative pressure is generated below the point where the compressed air is blown, so the pollen filled in the recess 21a is sucked from the opening 24a at the lower end of the ejector 24.

  As described above, pollen is sucked into the compressed air supplied from the compressed air generator 10, and a pollen mixture having a desired pollen content is generated by the powder mixture generator 20. In particular, since each recess 21a has the same volume, the same amount of pollen can always be taken into the compressed air. In addition, it can control to content of desired pollen by changing the rotational speed of the disc 21. FIG. In addition, the pollen content can be changed by changing the arc diameter of the groove or changing the supply amount or pressure of the compressed air amount.

<Description of Powder Mixture Feed Mechanism 30>
The pollen mixture generated by the powder mixture generator 20 is sent to the powder mixture feeding mechanism 30 through the pipe 25 and the branch pipes 25a and 25b. As described above, the powder mixture feed mechanism 30 includes the first feed mechanism 30a configured by the blower 32a and the pipe 34a connected to the branch pipe 25a, and the pipe 34b connected to the blower 32b and the branch pipe 25b. The 2nd sending mechanism 30b comprised by these.

  In the first feeding mechanism 30a, a pollen mixture having a pressure higher than the blowing pressure is blown into the air blown by the discharge force of the blower 32a to generate a pollen mixture with an increased amount of air, and the first To the outlet 40a of the swirling flow generator 40. Here, in the pipe 34a, the distance from the connection point 34c with the branch pipe 25a to the outlet 40a of the first swirling flow generating device 40 takes a value that is five times or more the inner diameter of the branch pipe 25a. A pollen mixture having a uniform pollen concentration is obtained. In the present embodiment, the inner diameter of the pipe 34a is 10 cm, and the distance between the connection point 34c and the outlet 40a is set to 50 to 100 cm.

  Further, the second feeding mechanism 30b also has the same dimensions and structure, and is arranged almost symmetrically with the first swirling flow generating device 40 as the center.

(Description of powder scattering means 4)
As described above, the pollen mixture fed by the powder mixture feeding mechanism 30 is dispersed by the powder scattering means 4 including the first swirl flow generating device 40 and the second swirl flow generating device 42. Then, it descends while turning in the chamber 2 to form a uniform pollen concentration distribution in the chamber 2.
<Description of First Swirling Flow Generator 40>
The pollen mixture fed from the powder mixture feed mechanism 30 is first blown into the chamber 2 through the first swirl flow generator 40. FIG. 4 shows a cross-sectional view for illustrating the structure of the first swirl flow generator 40. 4A is a cross-sectional view of the first swirling flow generating device 40 as viewed from the arrow B in FIG. 1A, and FIG. 4B is viewed from the arrow D in FIG. 4A. It is sectional drawing (viewed from the top).

As shown in FIG.4 (b), the pollen mixture sent in from the piping 34a is blown in the tangential direction of the annular flow path 40c from the blower opening 40a. Similarly, the pollen mixture sent from the pipe 34b is blown in the tangential direction of the annular channel 40c from the blow port 40b. A cylindrical central wall 40d is provided at the center of the first swirl flow generator 40, and an annular flow path 40c is formed.
As described above, the pollen mixture swirls in the annular flow path 40c of the first swirling flow generator 40, and this swirling flow gradually descends in the chamber 2 due to gravity. In addition, the true specific gravity of the pollen in this embodiment is about 1.6.

  In order to create a state of descending while swirling in the chamber 2, at least a blowing flow rate at which the pollen mixture blown in the circular flow path 40 c of the first swirling flow generating device 40 has a half or more circumference. It is considered necessary. In the present embodiment, the flow rate of the pollen mixture fed from the pipes 34a and 34b is 5 m / s or more.

<Description of Second Swirling Flow Generators 42a and 42b>
Next, FIG. 5 shows a state in which the pollen mixture is lowered while swirling inside the chamber 2 by the powder scattering means 4 including the first swirl flow generator 40 and the second swirl flow generator 42. Is schematically represented. The swirl flow of the pollen mixture generated by the first swirl flow generator 40 descends while gradually widening the swirl diameter along the shape of the octagonal pyramid roof. In this embodiment, the first swirling flow generating device 40 is installed at a height of about 4.2 m from the floor surface of the chamber 2, and the swirling speed gradually decreases as the pollen mixture descends. The swirl force is applied by the air blown from the two outlets 42a and 42b of the second swirl flow generating device 42 installed at a height of about 2 m from the floor of the floor.

  The outlets 42a and 42b of the second swirl flow generator 42 are installed on two opposite surfaces of the floor surface of the regular octagonal chamber 2, and in this embodiment, as the second swirl flow generator 42, An air conditioner having an air conditioning function is used. Therefore, air set to a desired temperature and humidity is blown in the tangential direction of the swirling flow of the pollen mixture (see the white arrow in FIG. 5), and a swirling force is added.

  Then, the pollen mixture is further lowered to lower the flow velocity, and at the position where the subject sitting on the chair placed in the chamber 2 breathes, that is, at a height of about 70 cm to 1 m from the floor surface, the pollen mixture turns. The flow velocity is very small. Therefore, unlike a conventional test apparatus that rotates pollen to disperse pollen, it is possible to simulate the same environment as when a person inhales pollen in nature.

  As described above, even in a large chamber 2 that can accommodate a large number of subjects, a uniform pollen concentration distribution can be obtained in the chamber 2 by lowering the pollen mixture while swirling it to disperse the pollen. It is possible to form. Therefore, the amount of pollen exposure received by each subject can be made constant, and a highly reliable exposure test can be performed. In addition, an environment in which the subject can stay in the chamber 2 for a long time is obtained by managing the temperature and humidity in the chamber 2 to appropriate values by the air conditioning function of the second swirl flow generator 42. Can do. In addition, various other natural conditions and environments can be simulated.

(Example)
Next, the measurement result of the pollen concentration distribution performed for confirming the performance of the powder scattering exposure apparatus of the present invention is shown below. This measurement was performed using an apparatus of the same type as that of the above-described powder scattering exposure apparatus.

<Test conditions>
First, the specifications and test conditions of the powder scattering exposure apparatus for measuring the pollen concentration distribution are shown below.
(1) Chamber 2
Floor: Regular octagon with an inscribed circle diameter of 6m Side wall: Height 2.5m from the floor
Roof part: Octagonal frustum roof elevation angle 30 degrees
Roof top height approx. 4.2m from the floor
(2) Powder mixture generator 20
Pollen mixing amount: 500 rotation speed scale, or
Rotational speed 250 scale (3) Powder mixture feed mechanism 30
Discharge amount of blower (sirocco fan) 32:
In case of 5m / s
1m / s in the weakest case
(4) First swirl flow generator 40
The outer diameter of the annular channel 40c: 60cm
Inner diameter of annular channel 40c: 58cm
The diameter of the injection ports 40a, b: 10cm
(5) Second swirl flow generator 42
Blowing flow velocity at the outlets 42a and 42b:
Strong case 10m / s
5m / s for weak

  Under the above specifications and conditions, the pollen mixture was blown into the chamber 2 and lowered while swirling to disperse the pollen into the chamber 2, and the pollen concentration distribution was measured. Here, each planar measurement position is shown in FIG. The measurement locations are a total of 17 locations (no points 9 and 10) indicated by white circles numbered from point 0 to point 18. The height of each measurement location is 70 cm high from the floor surface of the chamber 2 and coincides with the position where the subject inhales pollen. Moreover, the rectangle described as PC-300A and B shows the installation position in the case of installing an automatic pollen concentration measuring apparatus.

<Measurement method>
A measurement method at each measurement point from point 0 to point 18 will be described. The measurement was performed by leaving a slide glass coated with petroleum jelly on a desk 70 cm high from the floor for 20 minutes. Thereafter, this slide glass was dyed and covered with a cover glass, and the number of pollen in the measurement area of 1.8 cm × 1.8 cm square was measured with a microscope.

<Measurement results>
Next, the measurement results of the concentration of pollen at each measurement location are shown in the tables of FIGS. The measurement is performed 4 times in total, and the measurement time is 20 minutes for all. In each measurement, the measurement is performed by changing some conditions. The items whose conditions were changed were the pollen content of pollen mixture (described as “feeder” in the table), the blowing amount of the second swirling flow generator (described as “air conditioner air amount” in the table), and the discharge amount of the blower 32 ( It is described as sirocco fan in the table).

The value on the left side in each measurement value is the total number of pollen in each measurement region of 1.8 cm × 1.8 cm, and the value on the right side is the number of pollen per unit area (1 cm ² ).
Table 1 in FIG. 7 shows the measurement results when the conditions used in the normal pollen scattering exposure test are set. In the first measurement, the blowing speed of the second swirling flow generator 42 is weak (5 m / s), and in the second measurement, the blowing speed of the second swirling flow generator 42 is strong ( 10 m / s).

Regarding the number of pollen per unit area, in the first measurement result, the average value is 79 / cm ² , the maximum value is 106 / cm ² , and the minimum value is 62 / cm ² . Therefore, in the entire measurement region, the average value is within the range of −17 to average value + 27. Further, excluding the point 18, it is within the range of the average value +16.
Similarly, in the second measurement result, the average value is 69 pieces / cm ² , the maximum value is 91 pieces / cm ² , and the minimum value is 50 pieces / cm ² . Therefore, in the entire measurement region, the average value is within the range of -19 to the average value +22. Further, excluding the point 18, it is within the range of the average value +9.

  From the above measurement results, according to the powder scattering exposure apparatus of the present invention, even when a large number of subjects such as 30 are accommodated in the chamber 2 and an exposure test is performed, a sufficiently reliable test is performed. A possible pollen concentration distribution was obtained.

  In the third and fourth measurements, conditions different from those in the normal powder scattering exposure test were set, the concentration distribution was measured, and the influence on the changed pollen concentration distribution was examined. The results are shown in Table 2 in FIG.

First, in the 3rd measurement, compared with the 1st and 2nd measurement, it measured by setting the discharge amount of the air blower 32 to the weakest (1 m / s). In the measurement results, in the number of pollen per unit area, the average value is 65 / cm ² , the maximum value is 85 / cm ² , and the minimum value is 41 / cm ² . Therefore, in the entire measurement region, the average value is in the range of −24 to average value + 20.
Therefore, from the above measurement results, it is considered that the variation in the pollen concentration distribution is slightly increased by reducing the discharge amount of the blower 32.

  In the fourth measurement, the pollen content is measured in a state where the pollen content is halved to a rotational speed of 250 in comparison with the first and second measurements, and the pollen content of the pollen content in the pollen mixture is measured. The effect on concentration distribution was investigated.

In the fourth measurement result, the average value is 106 pieces / cm ² , the maximum value is 138 pieces / cm ² , and the minimum value is 57 pieces / cm ² . Therefore, in the entire measurement region, the average value is in the range of −81 to the average value + 32, and the variation in the density distribution is considerably larger than that in the normal condition as described above.

  As described above, by giving an appropriate set value to the powder scattering exposure apparatus of the present invention, it is possible to form a uniform pollen concentration distribution that allows a reliable exposure test.

(Other embodiments)
In the above powder scattering exposure apparatus, pollen is used as the powder to be handled, but any other powder can be used. Moreover, although the cross-sectional shape (floor shape) of the above-mentioned chamber is a regular octagon, various other shapes such as a circle can be adopted. The size of the chamber is not limited to the above-described embodiment, and any size can be adopted.

  In the above-described embodiment, pollen is sucked into compressed air by negative pressure due to the flow of compressed air, and pollen is contained in the air. However, other methods such as a method in which pollen is blown into air and contained are included. Any method can be adopted. In the above-described embodiment, compressed air containing pollen is blown into the air blown by the blower. Depending on the flow rate, flow rate, and pollen concentration of the pollen mixture, the compressed air containing pollen is used as it is. It can supply to a chamber and other various ventilation methods can be employ | adopted.

In the above-described embodiment, the powder mixture is swirled in the chamber by the first and second swirling flow generators. However, in addition to swirling the powder mixture, an upward or downward airflow is also provided. It is also possible to give
Furthermore, the powder scattering exposure apparatus of the present invention is not limited to the above-described embodiment, and various other embodiments are included in the powder scattering exposure apparatus of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS It is an external view which shows one embodiment of the powder scattering exposure apparatus of this invention, (a) shows a top view, (b) shows a side view. It is sectional drawing seen from the arrow A of FIG.1 (b). (A) is the figure which represented typically each apparatus of the powder mixture generator 20, (b) is detailed of each recessed part 21a which comprises the groove | channel of the disc 21 shown by the arrow C of (a). It is a figure which shows a cross-sectional shape. Sectional drawing for showing the structure of the 1st swirl | vortex flow generator 40 is shown, (a) is sectional drawing seen from the arrow B of Fig.1 (a), (b) is FIG.4 (a). It is sectional drawing seen from arrow D. FIG. 3 is a diagram schematically showing a state in which a pollen mixture is lowered while swirling inside a chamber 2 by a powder scattering means 4. It is a figure which shows the planar measurement position of the pollen density | concentration using the powder scattering exposure apparatus of this invention. It is a table | surface which shows the density distribution (the 1st, 2nd measurement value) of the pollen in each measurement location shown in FIG. It is a table | surface which shows the density distribution (3, 4 times measured value) of the pollen in each measurement location shown in FIG.

Explanation of symbols

2 Chamber 2a Front chamber 2b Air shower room 3 Powder mixture supply means 4 Powder scattering means 10 Compressed air generator 11 Compressor 12 Dryer 13 Flow control valve 14 Pipe 20 Powder mixture generator 21 Disc 21a Recess 22 Drive device 23 Pollen storage chamber 23a Spout 24 Ejector 25 Pipe 25a Branch pipe 25b Branch pipe 26 Scraper 30 Mixture feeding mechanism 30
30a First feeding mechanism 30b Second feeding mechanism 32a Blower 32b Blower 34a Pipe 34b Pipe 34c Connection point 34d Connection point 40 First swirling flow generator 40a Blow port 40b Blow port 40c Flow path 40d Center wall 42 First wall 42 Swirl generator 42a Air outlet 42b Air outlet 50 Intake device 52 Exhaust device 54 Blower

Claims (9)

A chamber capable of shutting off the entry and exit of powder,
Powder mixture supply means for supplying a gas (powder mixture) containing powder to the chamber;
Powder scattering means for causing the powder mixture supplied by the powder mixture supply means to flow in the chamber so as to swirl, and for scattering the powder into the chamber;
A powder scattering exposure apparatus comprising:   The powder scattering means includes a first swirling flow generating device having an annular flow path and at least one blowing port for blowing the powder mixture in a tangential direction of the annular flow path. The powder scattering exposure apparatus according to claim 1.   The said powder scattering means contains the 2nd swirl flow generator which has at least 1 blower outlet which ventilates in the tangential direction of the said swirl flow by the said 1st swirl flow generator. The powder scattering exposure apparatus according to 1.   The first swirl flow generating device is installed in an upper part of the chamber, and the second swirl flow generating device is installed below the installation position of the first swirl flow generating device. Item 4. The powder scattering exposure apparatus according to Item 3.   The powder scattering exposure apparatus according to claim 4, wherein the second swirl flow generating device is installed above a position where the subject sucks the powder mixed gas in the chamber.   The powder scattering exposure apparatus according to any one of claims 3 to 5, wherein the second swirl flow generator can further perform air conditioning in the chamber.   The powder scattering exposure apparatus according to any one of claims 1 to 6, wherein a cross-sectional shape of the chamber is a circle or a regular polygon having 6 or more corners.   The powder mixture supplying means has a predetermined powder concentration by blowing compressed air containing powder sucked using a negative pressure due to a gas flow into air blown by a blower. The powder scattering exposure apparatus according to any one of claims 1 to 7, wherein air is supplied.   The powder scattering exposure device according to any one of claims 1 to 8, wherein the powder is pollen.

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