JP4890193B2 - Mask collection performance tester and test method using the same - Google Patents

Description

  The present invention relates to a tester suitable for evaluating the collection performance of particulate matter such as pollen by a mask and a test method using the tester.

Conventionally, various mask performance test methods for collecting particulate matter such as dust and pollen floating in the air are known. For example, in JIS T 8159 (2006 edition) “Leakage rate test method for respiratory protective equipment” (Non-Patent Document 1), air containing NaCl particles at a rate of 8 ± 4 mg / m ³ is placed in a chamber which is a test room. The concentration of NaCl particles inside and outside the mask worn by the tester in the chamber is measured to evaluate the collection performance of the mask. In addition, the National Life Center website http: // www. kokusen. go / jp / news / data / n-20040205_2. html (Non-Patent Document 2) describes a mask evaluation method and an evaluation result mainly for collecting pollen and the like. According to the evaluation method, 10 g of flour is sprayed while stirring air with a fan in a highly airtight 6 tatami room test chamber conditioned at a temperature of 23 ° C. and a humidity of about 50%. The subject wearing the mask enters the test room, and the air inside and outside the mask is sampled 1 liter at a time, and the number of flour particles in the air is measured with Rion Particle Counter KC-01D.
JIS T 8159 (2006 version) “Leakage rate test method for respiratory protective equipment” National Life Center homepage http: // www. kokusen. go / jp / news / data / n-20040205_2. html

NaCl particles employed in the test method specified in JIS T 8159 have a median particle size of 0.06 to 0.1 μm and pass through a duct and a distributor provided at the top of the test chamber. Flow into the chamber. The air flow velocity in the vicinity of the subject's head inside the test chamber is defined to be 0.12 to 0.2 m / s. On the other hand, pollen such as cedar pollen to be collected with a mask having a simple structure for preventing hay fever has a particle size of 20 to 40 μm. And the sedimentation velocity W in the air of the spherical object in the region where the sedimentation velocity is small is ρgD ² / (18α) (ρ: specific gravity of pollen, g: gravitational acceleration, D: particle size, α: air dynamic viscosity). Probably proportional. Therefore, when pollen or particulate matter with the same particle size is used in place of NaCl particles in the test method of JIS T 8159, more particles settle on the floor of the test room, and a small amount of particulate matter. It becomes difficult to conduct the test efficiently. This tendency becomes more prominent as the time for continuing the test becomes longer. In addition, when the test is repeatedly performed in this test room, the test room must be cleaned at the end of the test. However, it takes considerable time to remove pollen adhering to the floor and walls.

  In the evaluation method adopted by the National Life Center, flour is used as a particulate matter instead of pollen, and the flour is suspended by stirring the air in the test chamber with a fan. Is about 5 μm, which is much smaller than the particle diameter of pollen such as cedar pollen, so that this evaluation method is not necessarily appropriate as a method for evaluating a mask whose main purpose is collection of pollen or the like. Can occur. Even in the case of this evaluation method, it is difficult to resuspend particulate matter such as flour that has settled on the floor with a fan. In particular, particulate matter that has settled in the corners of the test chamber is generally very difficult to resuspend. Therefore, in this evaluation method, when setting the suspended particulate matter to a required concentration, it is necessary to supply extra particulate matter suitable for the amount of particulate matter that settles into the room. The problem is that the amount used tends to increase. Even in the case of this evaluation method, when the test is repeatedly performed, there may be a problem that it takes considerable time to remove the particulate matter settled on the floor surface and the particulate matter adhering to the wall surface.

  One of the problems to be solved by the present invention with respect to such a conventional situation is that pollen or a substance having a large particle size corresponding to pollen is used as the particulate matter, and the particulate matter is captured in the mask. This is to provide a testing machine that can evaluate the collection performance. Another object of the present invention is to provide a testing machine that can easily float such particulate matter in the air. Furthermore, another object of the present invention is to provide a tester that can easily perform a test for evaluating the collection performance of a mask.

  In order to solve the above problems, the present invention is directed to a mask collection performance tester and a mask collection performance test method using the tester. The present invention relating to the testing machine is particularly intended for a test chamber capable of suspending particulate matter in the air and a test mask that can be attached and removed in the test chamber. A tester having an air intake part capable of sucking the air from the inside of the mask attached and a collection part for collecting the particulate matter in the air sucked into the air intake part. .

  In such a testing machine, the present invention is characterized as follows. The inner surface of the test chamber includes a top surface portion, a bottom surface portion facing the top surface portion, and a side surface portion interposed between the top surface portion and the bottom surface portion. The top surface portion and the bottom surface portion are connected by an air pipe provided outside the test chamber, and the test chamber and the air piping circulate the air in a direction from the top surface portion toward the bottom surface portion. A possible circulation path is formed. The air pipe is provided with a fan for circulating the air and a supply unit capable of supplying the particulate matter from the outside of the circulation path to the inside of the circulation path. The intake portion is formed such that a tip portion inside the test chamber can attach and remove the mask. The collection portion is provided in an intake passage that extends from the tip portion of the intake portion to the outside of the test chamber and forms a part of the intake portion, and sucks the air in the intake portion. A filter capable of collecting the particulate matter is detachably formed below.

  In one preferred embodiment of the present invention, the bottom surface portion of the test chamber is formed such that the inner diameter of the test chamber gradually decreases from the top to the bottom of the test chamber, The air pipe extends from the lowermost part.

  In another preferred embodiment of the present invention, the bottom surface portion is formed in an inverted conical shape.

  In another preferred embodiment of the present invention, the side portion of the test chamber is formed in a cylindrical shape.

  In another preferred embodiment of the present invention, the test chamber has a nozzle capable of injecting compressed air for cleaning from a tangential direction to the cylindrical side surface portion.

  In another preferred embodiment of the present invention, the top surface portion of the test chamber is formed so that the inner diameter gradually increases from the top to the bottom of the test chamber.

  In another preferred embodiment of the present invention, the filter is a bag-like filter, and the particulate matter is collected inside the bag-like filter.

  In still another preferred embodiment of the present invention, the tip portion of the air intake portion is a human head model.

  This invention which concerns on the collection performance test method of a mask uses the testing machine in any one of Claims 1-8 in the collection performance test method of the mask which can collect the particulate matter which floats in the air It is characterized by doing.

  In one of the preferred embodiments of the present invention relating to the mask collection performance test method, the test is performed while supplying an air amount corresponding to the suction amount of the intake portion in the test machine to a circulation path provided in the test machine. Drive the machine. In another preferred embodiment of the present invention, the air amount is supplied using air conditioned by an air conditioner provided in the testing machine.

  In the mask collection performance testing machine according to the present invention, an air circulation path is formed by a test chamber and an air pipe outside the test chamber and connecting the top surface portion of the test chamber and the bottom surface portion of the test chamber. Therefore, circulating the air makes it easy to mix and disperse the particulate matter supplied to the circulation path during the test, and prevent sedimentation of the particulate matter even if the test time is long. it can. A mask can be attached to the intake section provided in the test chamber, and particulate matter contained in the air sucked into the inside of the mask is collected with a filter, and the change in the weight of the filter is measured. You can know the performance.

  In this aspect of the invention in which the inner diameter of the bottom surface of the test chamber gradually decreases from the top to the bottom and the air piping extends from the bottom of the bottom surface, the particulate matter in the test chamber flows toward the air piping. Therefore, even if the particulate matter settles on the floor surface of the test room, it can be prevented from being deposited on the floor surface. In addition, if the bottom surface is so, even if the test is repeatedly performed, it does not take time to clean the test chamber.

  According to the present invention in which the bottom surface portion of the test chamber is formed in an inverted conical shape and the aspect in which the side surface portion of the test chamber is formed in a cylindrical shape, cleaning of the test chamber after completion of the test becomes easier. .

  In this aspect of the invention in which the test chamber has a nozzle capable of ejecting compressed air for cleaning from the tangential direction with respect to the cylindrical side surface portion, particles adhering to the side surface portion due to the ejection of the compressed air The substance can be easily removed.

  In this aspect of the invention where the inner diameter of the top surface portion of the test chamber gradually increases from the top to the bottom, the flow rate of the circulating air is increased inside the air pipe to prevent sedimentation of particulate matter, The flow velocity can be lowered in the test chamber and can be brought close to a natural state in the vicinity of the mask.

  In this aspect of the invention using a bag-like filter as a filter for collecting the particulate matter in the sucked air, the collected particulate matter does not scatter when weighing the filter. The filter is easy to handle.

  In the present invention in which the front end portion of the air intake portion is a human head model, it is possible to evaluate the quality of the contact state of the mask with the face.

  According to the mask collection performance test method using the testing machine according to the present invention, it is easy to repeat relative evaluation of the mask related to the collection performance. In such a test method, when the test machine is operated while supplying an air amount corresponding to the air suction amount of the intake portion to the circulation path, the circulation path is not excessively depressurized. Moreover, if the air conditioned by the air conditioner is used in the operation, the temperature and humidity conditions of the circulation path are not changed.

  The details of the mask performance testing machine according to the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a piping system diagram of the mask performance testing machine 1. This testing machine 1 is suitable for evaluating the collection performance of particulate matter such as pollen in a mask 2 having a simple structure worn in daily life in order to prevent hay fever and the like. The mask 2 having a simple structure is a woven fabric such as nonwoven fabric or gauze, a fired plastic sheet or the like, and is worn using ear straps, etc. It means that it is not an indispensable condition when wearing a mask. A typical example of such a mask 2 is a commercially available disposable mask. In the testing machine 1 of FIG. 1, the test chamber 100 is set at the center, and an air intake unit 200, a dust collector 300, an air conditioner 400, a particulate matter supply unit 500, a particulate matter collection unit 600, and a compressed air supply unit around the test chamber 100 700 is arranged.

  The test chamber 100 has a cross-sectional shape shown in FIG. The bottom surface portion 113 and the top surface portion 112 are connected to each other through a pipe 114 extending from the bottom surface portion 113 to the top surface portion 111 on the outside of the test chamber 100. In the middle of the pipe 114, a circulation fan 116 is provided. In the test chamber 100, the air pipe 114, and the circulation fan 116, mixed air, which will be described later, in the direction of arrow A from the top surface portion 111 to the bottom surface portion 113 is provided. A circulation path L-1 that can be circulated is formed. Inside the test chamber 100 is placed a human head model 3 to which a mask 2 to be used for a test in the test machine 1 can be attached and removed. An enlarged pipe 117 is attached to the top surface portion 111 to reduce the flow velocity when the mixed air flowing through the pipe 114 enters the test chamber 100. A valve AB-V2, which is normally open, is attached to the pipe 114. In FIG. 1, the normal state means that the testing machine 1 is in the state of evaluating the performance of the mask 2.

  The intake portion 200 is provided in the middle of the human head model 3 forming the tip portion thereof, the intake passage L-5 extending from the human head model 3 to the outside of the test chamber 100 and connected to the dust collector 300, and the intake passage L-5. The intake fan 201, the air volume sensor 202 provided in the intake passage L-5 on the upstream side of the intake fan 201, the air volume monitoring controller 203 interposed between the air volume sensor 202 and the intake fan 201, and the rotation of the intake fan. And a control inverter 204. The intake passage L-5 is connected to a mouth and a nostril (not shown) formed in the human head model 3 so as to be able to inhale air, and is mixed in the test chamber 100 from the inside of the mask 2 by the action of the intake fan 201. Air can be aspirated. The mixed air flowing through the intake passage L-5 after being sucked passes through the collection unit 600 and the air volume sensor 202, and the flow velocity when passing through the air volume sensor 202 is measured. The actually measured value of the flow velocity is collated with a specified value in the controller 203, and the inverter 204 controls the rotation of the intake fan 201 based on the difference between the two, and brings the flow velocity in the intake passage L-5 closer to the specified value. The mixed air is released into the atmosphere through a dust collector 300 provided on the downstream side of the intake fan 201.

  The collection unit 600 is airtight and includes a housing 601 and a lid 602, and a bag-like filter 603 can be attached to and detached from the inner surface of the lid 602. An intake passage L-5 extending from the test chamber 100 enters the lid 602, and the intake passage L-5 opens toward the inside of the filter 603. From the housing 601, an intake passage L-5 extends toward the air volume sensor 202. Therefore, the mixed air sucked in the human head model 3 enters the filter 603 through the intake passage L-5, proceeds to the inside of the housing 601 while being filtered there, and further passes through the intake passage L-5 to the air volume sensor 202. Head to. The filter 603 is formed of a material that can capture the particulate matter P mixed in the air with a high collection rate. The filter 603 can know the amount of collected particulate matter by measuring the weight before and after the test in the testing machine 1.

  The air conditioner 400 is connected to the test chamber 100 and the particulate matter supply unit 500 via the air supply path L-4. Prior to the start of the test in the test machine 1, the temperature / humidity conditions of the test chamber 100 and the supply unit 500 can be adjusted by sending out air adjusted in temperature and humidity from the air conditioner 400 in the direction of arrow C. Valves A-V11, V9, and V12 provided in the air supply path L-4 are normally closed, and are opened when air is sent out. The air sent to the test chamber 100 passes through the exhaust passage L-6a and is released to the atmosphere through the dust collector 300. The air sent to the supply part 500 goes to the dust collector 300 through the exhaust path L-6c.

  The particulate matter supply unit 500 is for supplying a required amount of particulate matter P such as pollen and pollen substitutes to be collected by the mask 2 to the air in the circulation path L-1, and for that purpose. A measuring instrument 501 and a vibrator 502 used as necessary to prevent the particulate matter P from being agglomerated are provided. A supply pipe L-2 connected to the air pipe 114 of the circulation path L-1 extends from the supply unit 500. In addition to the separator 503 being provided in the supply pipe L-2, valves V15, AB-V5, AB-V6 and AB-V7 are also provided, and the separator 503 and the valve AB-V5 are connected to each other. An air supply pipe L-3a extending from the compressed air supply unit 700 is connected therebetween. An exhaust pipe L-7 extends from the separator 503, and an exhaust fan 506 and valves V14 and A-V9 are attached to the exhaust pipe L-7. In order to guide the particulate matter P from the supply unit 500 to the air pipe 114, the valves V15 and AB-V5 of the supply pipe L-2, the valves V14 and A-V9 of the exhaust pipe L-7, and the air supply pipe L-3a The valves V13 and A-V10 are opened, and the exhaust fan 506 is rotated while sending compressed air to the air supply pipe L-3a to generate an air flow in the arrow B direction from the supply unit 500 toward the separator 503. The required amount of particulate matter P is pneumatically transported. In the separator 503, the particulate matter P is separated from the compressed air. After that, the valves AB-V6 and AB-V7 in the supply pipe L-2 are alternately opened for a required time, and the particulate matter P is intermittently introduced into the air pipe 114 of the circulation path L-1 little by little. . In the circulation path L-1, the circulation fan 116 is rotated to mix the air and the particulate matter P while the air is circulated, thereby obtaining mixed air having a required particle concentration. Injecting the particulate matter P little by little into the circulating air by alternately opening the valves AB-V6 and AB-V7 in the supply pipe L-2 disperses the particulate matter P uniformly. Preferred above. Further, by alternately opening the valves AB-6V and AB-V7 in this way, it is possible to prevent a large amount of compressed air from entering the circulation path L-1. Since the supply unit 500 is connected to the dust collector 300 via the exhaust pipe L-6a, the air flowing into the supply unit 500 from the air conditioner 400 can be discharged into the atmosphere via the dust collector 300.

  The compressed air supply unit 700 includes a pressure reducing valve 701, a filter 702, and an air supply pipe L-3. From the air supply pipe L-3, the air supply pipes L-3a, L-3b, L-3c, and L- 3d is branched. The air supply pipe L-3a extends to the supply pipe L-2. The air supply pipe L-3b is branched into a plurality of cleaning pipes 711, 712, 713, 714, 715, 716, 717 extending to the test chamber 100. Valves A-V1 to A-V7 and V1 to V7 that are normally closed are attached to the cleaning pipes 711 to 717, respectively. Of the cleaning pipes 711 to 717, the pipes 711 and 717 extend to the enlarged pipe 117 and the bottom surface 113, and compressed air can be ejected to the inside thereof. The pipes 712 to 716 have nozzles (see FIGS. 2, 3, and 4) that extend to the side surface portion 112 and can eject compressed air from the tangential direction to the side surface portion 112. The air pipe L-3c is connected to the dust collector 300, and an air gun 718 is attached to the air pipe L-3d. Valves V18 and V17 in these air supply pipes L-3c and L-3d are normally closed.

  In the piping system diagram of FIG. 1, in addition to the above, exhaust pipes L-7 and L-8 and an intake pipe L-9 are attached to the test chamber 100. The exhaust pipe L-7 has valves V11 and A-V8 that are normally closed, and a filter 118, and is used as necessary when air from the air conditioner 400 is allowed to escape. The exhaust pipe L-8 has a valve V8 that extends outward from the top surface portion 111 and is normally closed, and is appropriately used when the test chamber 100 needs to be opened to the atmosphere. The intake pipe L-9 has a valve AB-V1 that is normally closed, and a filter 119, and can supply filtered air to the test chamber 100 when the test chamber 100 is cleaned. The pipe 716a extending between the exhaust pipe L-7 and the pipe 716 is particles that have settled inside the exhaust pipe L-7 by blowing compressed air from the pipe 716 into the exhaust pipe L-7. This is for sending the substance P to the test chamber 100. However, the test apparatus 1 can be operated without installing the exhaust pipe 716a.

  The testing machine 1 based on the piping system diagram of FIG. 1 is operated by the following procedure, for example.

  Procedure 1: After opening the door 121 (see FIG. 2) of the test chamber 100 and attaching the mask 2 to be tested to the human head model 3 placed in the test chamber 100, the door 121 is closed and the test chamber 100 is sealed. To do.

  Procedure 2: After weighing the bag-like filter 603, the bag-like filter 603 is attached to the lid 602 of the collection unit 600, and the housing 601 is sealed with the lid 602. When high accuracy is required for the amount of collected particulate matter P, it is preferable to use a filter 603 conditioned at the same temperature and humidity as the air supplied from the air conditioner 400.

  Procedure 3: The air conditioner 400 is operated and a predetermined temperature and humidity, for example, 23 ° C., R.P. H. 50% of the air is sent out to the test chamber 100, and the circulation path L-1 is circulated to condition the circulation path L-1. At this time, if necessary, any one of the valves A-V5, V-5, AB-V3, and V8 in the test chamber 100 can be opened to release the air in the test chamber 100 to the outside.

  Procedure 4: The circulation fan 116 is operated and air is circulated through the circulation path L-1, while a predetermined amount of the particulate matter P is pneumatically transported from the particulate matter supply unit 500 to the separator 503. Subsequently, the valves AB-V6 and AB-V7 are alternately opened and closed alternately at intervals of 3 to 5 seconds, for example, for about 30 seconds, and the particulate matter P is supplied to the air pipe 114. Obtain a mixed air that is dispersed and floating.

  Procedure 5: The intake fan 201 in the intake section 200 is operated to suck mixed air from an intake port (not shown) formed in the nose of the human head model 3 inside the mask 2. The intake fan 201 is controlled using the sensor 202, the controller 203, and the inverter 204 so that the air volume becomes a value in the range of, for example, 400 to 1700 cc / sec. If the suction of the mixed air is continued for a certain time, for example, 360 seconds, the supply pipe L positioned on the downstream side of the separator 503 with the compressed air from the air supply pipe L-3A with the valves V15 and AB-V5 closed. -2 is preferably blown into the interior of -2 for about 10 seconds, and the particulate matter P remaining in the supply pipe L-2 is preferably sent to the circulation path L-1. When the operation of the intake fan 201 is further continued and the total operation time of the intake fan 201 reaches a predetermined time, for example, 420 seconds, the intake fan 201 is stopped.

  Procedure 6: The filter 603 is taken out from the collection unit 600 and weighed.

  Procedure 7: The mask 2 is removed from the human head model 3 and the test chamber 100 is sealed again. While operating the dust collector 300, the compressed air from the compressed air supply unit 700 is blown against the expansion tube 117, the side surface portion 112, and the bottom surface portion 113 of the test chamber 100 using the cleaning pipes 711 to 717. The particulate matter P remaining in the water is discharged. At this time, the circulation fan 116 is also operated to discharge the particulate matter P remaining in the air pipe 114.

  In the testing machine 1 operated in this manner, the mask 2 is attached to the human head model 3 and is operated for a predetermined time, so that the particulate matter P that has passed through the mask 2 and the gap between the human head model 3 and the mask 2 are inserted. The particulate matter P that has entered can be collected by the filter 603. The magnitude of the collection amount, which is the weight difference of the filter 603 before and after the test, serves as a standard for judging whether the collection performance between the plurality of tested masks 2 is good or bad. The fact that the amount collected is small proves that the mask 2 is excellent as a filter medium for particulate matter and that the fitting property to the human head model 3 is excellent. The mask 2 having a simple structure used in daily life for the prevention of hay fever generally does not necessarily have means for strongly adhering the peripheral edge of the mask to the face. It is difficult to avoid a slight gap between the two. Therefore, in order to evaluate the collection performance of the mask 2, it is meaningful to take into account the particulate matter P entering from the gap between the mask 2 and the human head model 3. However, in the testing machine 1, the mask 2 can be evaluated by closing the gap between the mask 2 and the human head model 3 with an adhesive tape or the like. Needless to say, the size of the human head model 3 should be selected depending on whether the mask 2 is for adults or for children. Furthermore, it is also possible to evaluate by attaching the mask 2 to the tip portion of the intake portion 200 made in a shape different from the human head model 3.

When the test machine 1 evaluates the mask 2 for preventing hay fever, for example, Ishimatsuko can be used as a particulate material instead of the cedar pollen. Ishimatsuko is easily available and its particle size is 30-40 μm, which is close to that of cedar pollen. The weight is about 1.05 g / cc, which is slightly heavier than the weight of cedar pollen (about 0.70 g / cc). When Ishimatsuko is used as the particulate matter in the procedure 4, the circulation path L− having an internal volume of about 86,000 cc in the test chamber 100 and an internal volume of about 17,000 cc in the air pipe 114 is about 836,000 cc. For example, 3 g of Ishimatsuko is introduced into 1 unit. Further, in the circulation path L-1 of the test machine 1, the in-pipe wind speed of the air pipe 114 is set to 9 m / sec, for example, and this wind speed is set to 4 cm / sec in the test chamber 100 using the expansion pipe 117, for example. It is preferable to suck the mixed air with the human head model 3 while the stone matsuko slowly sinks in a state close to a natural environment. The suction amount of the mixed air in the intake section 200 having the human head model 3 can be set to an appropriate value. For example, the suction speed during normal breathing by an adult is about 400 cc / sec, but the suction speed is set to about 1700 cc / sec in order to expect sufficient performance for the mask 2. The bag-like filter 603 in the collection unit 600 has, for example, a weight of 87 g / m ² and a ventilation resistance value of 0.412 KPa · s / m so as to reliably collect stone mushrooms. A non-woven fabric having an effective surface area of about 71.5 cm ² is used. The airflow resistance value is a value measured using a KES-F8-AP-1 air permeability tester manufactured by Kato Tech Co., Ltd. (20 Nishikujo Karatocho, Minami-ku, Kyoto). If the stone mushrooms that have passed through the mask 2 are collected by the bag-like filter 603, it is possible to prevent the stone mushrooms from being scattered when the filter 603 is weighed, so that the weighing accuracy is improved.

  Further, in the illustrated testing machine 1, since the mixed air is circulated, if the test is continued for a long time, the concentration of the particulate matter P gradually decreases in accordance with the suction amount in the intake section 200. Concentration does not change significantly due to sedimentation of particulate matter. Since the test chamber 100 has a circular cross-sectional shape in the horizontal direction, there is no problem that the particulate matter P settles and accumulates at the corner of the test chamber 100 during the test. In the test chamber 100, since the bottom surface portion 113 has an inverted conical funnel shape, even if the particulate matter P settles on the bottom surface portion 113, it easily flows into the air pipe 114. Also in this respect, as a result, the sedimentation of the particulate matter P in the mixed air can be prevented. Therefore, according to the test method of the present invention using the testing machine 1, the particulate matter P can be easily dispersed or suspended in the air. I don't use it a lot. Further, in the cleaning pipes 712 to 716, the cleaning compressed air is ejected from the tangential direction to the cylindrical side surface portion 112, so that the particulate matter P adhering to the side surface portion 112 can be easily removed. It is.

  2, 3, and 4 are a front view of the test chamber 100, a side view of the front view, and a sectional view taken along the line IV-IV in FIG. 2. A door 121 made of transparent glass or plastic is attached to the front of the test chamber 100 in FIG. Further, cleaning pipes 711, 712, 713, and 714 and nozzles 711 a, 712 a, 713 a, and 714 a connected to these pipes are attached to the outer surface portions of the enlarged pipe 117 and the side surface portion 112. 3, cleaning pipes 715, 716, and 717 and nozzles 715a, 716a, and 717a connected to these pipe parts are attached to the outer surface portions of the side surface portion 112 and the bottom surface portion 113 of the test chamber 100. These nozzles 711a to 717a are attached with an inclination of about 10 degrees with respect to a horizontal plane so that the tip portion is on the bottom. FIG. 4 shows a tip portion 713b of the nozzle 713a. The front end portion 713 b is seen along the side surface portion 112, preferably so that compressed air can be ejected from the tangential direction to the side surface portion 112. The tip portions of the nozzles 711 a, 712 a, 714 a, 715 a, 716 a, and 717 a other than the nozzle 713 a are also looked into the test chamber 100. 2, 3, and 4, illustrations other than the door 121 and the cleaning pipes 711 to 717 are omitted.

  In the testing machine 1 shown in the drawing, it is preferable that the test chamber 100 has a circular cross-sectional shape in the horizontal direction, but the present invention can also be implemented with a polygonal cross-sectional shape. The test chamber 100 may also have a cleaning unit in place of the cleaning pipes 711 to 717 and the nozzles 711a to 717a in the illustrated example. In order to supply the particulate matter P to the circulation path L-1, various means in place of the means in the illustrated example can be used. Putting the particulate matter P into the circulation path L-1 by manual operation is an example of the means. As for the air intake section 200, it is possible to use one sheet-like filter instead of a different one from the illustrated example, for example, the bag-like filter 603. Furthermore, it is possible to replace the dust collector 300, the air conditioner 400, the compressed air supply unit 700, the piping associated therewith, and the like with a mode different from the illustrated example. Procedures 1 to 7 for operating the testing machine 1 are examples of the procedure, and it is also possible to operate the testing machine 1 by adding appropriate changes to them or omitting a part of the procedure.

  In the testing machine 1 according to the present invention, the internal pressure of the circulation path L-1 gradually decreases due to the action of the intake section 200. When the degree of the reduction may affect the test result in one test, the circuit L-1 can be recovered from the reduced pressure state to meet the degree of the reduction, that is, Moreover, in order not to change the temperature and humidity conditions of the circulation path L-1, for example, clean air that has been conditioned by the air conditioner 400 and filtered by a filter having a higher collection performance than the filter 603 is used as the circulation path L-1. It is preferable to carry out the test while supplying Needless to say, the testing machine 1 can also perform a filtration performance test on a breathable filtration material other than the mask 2. Depending on the shape and properties of the filterable material, the human head model 3 can be changed to an appropriately shaped fixture.

  According to the present invention, it is possible to manufacture a mask collection performance tester that can easily mix and disperse particulate matter in the air, and to perform a mask collection performance test using the tester.

Piping system diagram of testing machine. The front view of a test room. A side view of a test room. The figure which shows the IV-IV line | wire cut surface of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Test machine 2 Mask 100 Test chamber 111 Top surface part 112 Side surface part 113 Bottom surface part 200 Intake part 600 Collection part 603 Filter L-1 Circulation path P Particulate matter

Claims (11)

A test chamber in which particulate matter can be suspended in the air, and an intake air that is formed so that a test mask can be attached and removed in the test chamber and that can suck in the air from the inside of the attached mask. A mask collection performance tester having a portion and a collection portion for collecting the particulate matter in the air sucked into the intake portion,
The inner surface of the test chamber includes a top surface portion, a bottom surface portion facing the top surface portion, and a side surface portion interposed between the top surface portion and the bottom surface portion, and the top surface portion and the bottom surface portion are the test. It is connected by an air pipe provided outside the chamber, and the test chamber and the air pipe form a circulation path through which the air can circulate in the direction from the top surface portion toward the bottom surface portion. ,
The air pipe is provided with a fan for circulating the air, and a supply unit capable of supplying the particulate matter from the outside of the circulation path to the inside of the circulation path,
The intake section is formed so that the tip portion inside the test chamber can be attached to and detached from the mask,
The collection portion is provided in an intake passage that extends from the tip portion of the intake portion to the outside of the test chamber and forms a part of the intake portion, and sucks the air in the intake portion. The testing machine according to claim 1, wherein a filter capable of collecting the particulate matter is detachably formed below.   The bottom surface portion of the test chamber is formed so that an inner diameter of the test chamber gradually decreases from an upper side to a lower side of the test chamber, and the air pipe extends from a lowermost portion of the bottom surface portion. Item 1. The testing machine according to item 1.   The testing machine according to claim 1, wherein the bottom surface portion is formed in an inverted conical shape.   The testing machine according to claim 1, wherein the side surface portion of the test chamber is formed in a cylindrical shape.   The test machine according to claim 4, wherein the test chamber has a nozzle capable of jetting compressed air for cleaning from a tangential direction with respect to the cylindrical side surface portion.   The testing machine according to any one of claims 1 to 5, wherein the top surface portion of the test chamber is formed so that an inner diameter gradually increases from an upper side to a lower side of the test chamber.   The test machine according to any one of claims 1 to 6, wherein the filter is a bag-shaped filter, and the particulate matter is collected inside the bag-shaped filter.   The testing machine according to claim 1, wherein the tip portion of the intake portion is a human head model. A mask collection performance test method capable of collecting particulate matter floating in the air,
The said test method characterized by using the testing machine in any one of Claims 1-8.   The test method according to claim 9, wherein the test machine is operated while supplying an air amount corresponding to a suction amount of an intake portion in the test machine to a circulation path provided in the test machine.   The test method according to claim 10, wherein the air amount is supplied using air conditioned by an air conditioner provided in the test machine.

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