JPH09243566A - Detection apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a detection apparatus capable of judging a change of the concn. of an alkaline substance in air present on the primary side or secondary side or primary and secondary sides of an air filter with the elapse of time and the total amt. of the alkaline substance removed within a definite time by the air filter. SOLUTION: A detection apparatus is equipped with a granaular reaction material discolored upon the reaction with an alkaline substance contained in air guided to a ventilation passage and a measuring pipe 10 having air permeable partition materials 10c on air outflow and inflow sides 10b, 10a and having the reaction material 20 between the partition materials 10c. The measuring pipe 10 has light permeability capable of visually confirming at least a part of the reaction material 20 sealed in the pipe 10 from the outside and one end part thereof communicates with the ventilation passage and the measuring pipe 10 is equipped with a flow velocity regulating means 30 maintaining the flow velocity of air flowing in the measuring pipe 10 so that the reaction material 20 sealed in the measuring pipe 10 is gradually discolored with the elapse of time from the air inflow side 10a of the measuring pipe 10 to the air outflow side 10b thereof.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a space required for air to be processed by an air filter such as a dust removal filter and a gas adsorption filter, typically a clean room for manufacturing electronic parts such as semiconductors and ICs, An air filter installed in a ventilation path that supplies air to the space inside various manufacturing equipment for the electronic parts installed in a clean room, or the space such as an art museum where paintings are displayed, the exhibition space of a museum, etc. The present invention relates to a detection device for detecting an alkaline substance contained in the air guided through the ventilation path on the primary side or the secondary side or on the primary side and the secondary side.

[0002]

2. Description of the Related Art In various clean rooms, museums, museum exhibition rooms, etc., alkaline substances contained in the atmosphere, especially small amounts of ammonia gas, which is usually contained in the atmosphere at about 5 to 20 PPb, are used. Supply of the removed air is required.

Further, in various manufacturing apparatuses used for manufacturing electronic parts such as semiconductors and ICs, it is required to supply air from which alkaline substances such as ammonia gas have been removed to the space inside the apparatus. Has been.

Therefore, in various clean rooms at present, an air filter for removing alkaline substances such as ammonia gas contained in the atmosphere is installed in the air passage for supplying the air to be processed to the clean room.
The clean room is configured, and such an air filter is also installed in a ventilation path that supplies air to an exhibition room such as a museum.

Alkaline substances such as ammonia gas are also removed from the air passages provided in the manufacturing apparatus for supplying air in the clean room to the spaces in various manufacturing apparatuses used for manufacturing electronic parts such as semiconductors. An air filter is installed.

[0006] Therefore, in these facilities and apparatuses such as clean rooms, whether the alkaline substance is properly removed by the air filter, and how much ammonia gas is supplied to the air sent to the air filter. The presence of alkaline substances will be an important concern. That is, when the air on the secondary side of the air filter contains an alkaline substance such as ammonia gas in a concentration exceeding the required concentration, it is immediately requested to take measures such as replacement of the air filter. Further, when the air on the primary side of the air filter contains an alkaline substance such as ammonia gas in a concentration exceeding the concentration usually contained in the atmosphere, the service life of the air filter is shorter than usual. It is expected that the air filter will be replaced, and measures such as advancing the replacement time of the air filter are requested.

For this reason, the air on the primary side or the secondary side of such an air filter has been conventionally sampled at any time, and the concentration of alkaline substances such as ammonia gas in the sampled air is usually determined by ion chromatography. It was measured by the graph method.

[0008]

However, the concentration of alkaline substances such as ammonia gas contained in the atmosphere is
In the air in the clean room, which is increased or decreased over time and due to changes in the surrounding environment, etc., and is sent to the ventilation passage provided in the manufacturing apparatus for the electronic parts and the like installed in the clean room. The concentration of the alkaline substance such as ammonia gas is not uniform, and the measurement by the ion chromatography method is limited to showing the concentration of the alkaline substance such as ammonia gas in the sampled air at the time of the sampling. Therefore, even if the air on the primary side of the air filter is measured by this method, it is not possible to determine how much amount of an alkaline substance such as ammonia gas has been fed into the air filter over time. It was

For this reason, conventionally, in order to ensure safety, it has been unavoidable to replace the air filter with a relatively long service life of the air filter predicted from the measurement result.

In addition, the measurement by the ion chromatograph method requires not only specialized knowledge and operation for the measurement, but also the inconvenience that the equipment for performing the measurement is relatively complicated and expensive. It was

[0011] Therefore, the present invention has an object to eliminate such a conventional inconvenience.

Further, it is possible to easily and reliably change the concentration of the alkaline substance in the air on the primary side or the secondary side or on the primary side and the secondary side of the air filter with the passage of time and to remove the alkaline substance within a certain time. It is an object of the present invention to provide a detection device capable of determining the total amount of alkaline substances.

Further, it is possible to measure an alkaline substance in the air without requiring specialized knowledge and operation, and to provide a detection device which can be provided at a low cost with a relatively simple structure. To aim.

[0014]

In order to achieve the above object, in the present invention, a detection device is provided with an air passage P for supplying air to a space S where air to be processed by an air filter F is required.
On the primary side or the secondary side or on the primary side and the secondary side of the air filter F installed in the air filter F for detecting an alkaline substance contained in the air guided through the air passage P.
And The detection device M is a granular reactant 20 that changes color by reacting with an alkaline substance contained in the air guided to the air passage P, one end of which is the inflow side 10a of the air, and the other end is the other end. As the outflow side 10b of the air, and the outflow side 10b and the inflow side 10a each provided with a breathable partition member 10c, and the reaction tube 20 enclosed between the partition members 10c. And with. Further, the measurement tube 10 constituting the detection device M has a light-transmitting property such that at least a part of the enclosed reactant 20 is visible from the outside, and one end of the measurement tube 10 has the ventilation path. It is assumed that the reactant 20 is in contact with P, and the reactant 20 enclosed in the measurement pipe 10 is connected to the air from the air inflow side 10a to the outflow side 10b of the measurement pipe 10.
The measuring tube 1 so that the color gradually changes toward
Flow rate adjusting means 30 for keeping the flow rate of the air flowing into
Was provided.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION A typical embodiment of the present invention will be described below with reference to FIGS.

The detection device M according to this embodiment is provided with a primary side, a secondary side or a primary side of the air filter F installed in the air passage P for supplying air to the space S where the air to be processed by the air filter F is required. A detection device M for detecting an alkaline substance contained in the air guided through the air passage P on the side and the secondary side, and the detection device M is included in the air guided through the air passage P. The granular reactant 20 which changes color by reacting with the alkaline substance, one end of which is the inflow side 10a of the air and the other end is the outflow side 10b of the air, and the outflow side 10b and the inflow side 10
a and a breathable partitioning member 10c, and the partitioning member 1
The measuring tube 10 in which the reactant 20 is enclosed between 0c, and at least a part of the enclosed reactant 20 is visible from the outside of the measuring tube 10 constituting the detection device M. It is assumed that one end of the measuring tube 10 is connected to the ventilation path P, and the reactant 20 enclosed in the measuring tube 10 has the translucent property.
The flow rate adjusting means 30 for maintaining the flow rate of the air flowing into the measuring tube 10 is provided so that the color gradually changes from 0 toward the outflow side 10b of the air.

Therefore, when the air guided in the air passage P is introduced into the measuring tube 10 which constitutes the detecting device M according to this embodiment as described above, the alkaline substance contained in the air causes The reactant 20 enclosed in the measuring tube 10 is gradually discolored with time from the air inflow side 10a toward the air outflow side 10b.

As a result, according to the detection device M of this embodiment, the time during which the air is flown into the measuring tube 10 and the inflow of the air into the reaction body 20 enclosed in the measuring tube 10. From the length of the color change area from the side 10a to the outflow side 10b, the reaction product 2 per unit time
A discoloration length of 0 can be easily recognized. And
The discoloration length of the reactant 20 per unit time,
The time-dependent increase / decrease in the amount of alkaline substance contained in the air can be easily determined by comparing the length of the discolored area of the reactant 20 enclosed in the measuring tube 10 thereafter.

In addition, from the inflow side 10a of the air to the outflow side 1 of the reactant 20 enclosed in the measuring tube 10.
From the length of the color change area toward 0b and the amount of the alkaline substance required when the reactant 20 changes color for a predetermined length, the alkaline substance contained in the air flowing into the measuring tube 10 is measured. Can be easily determined.

As a result, according to the detecting device M of this embodiment, the detecting device M is arranged so that the air on the primary side of the air filter F may flow into the measuring pipe 10.
2 is installed (FIG. 2), it is possible to monitor changes in the amount of alkaline substances contained in the air sent to the air filter F over time, and to measure the flow rate of air on the primary side of the air filter F. By keeping the flow velocity of the air flowing into the measuring pipe 10 at a constant speed, the flow rate of the air flowing into the measuring pipe 10 and the air sent into the air filter F within a predetermined time period can be reduced. From the ratio of the flow rates, the total amount of alkaline substances in the air sent into the air filter F within the predetermined time can be determined, and the remaining service life of the air filter F can be easily and reliably determined. You can Further, by keeping a predetermined flow velocity ratio between the flow velocity of air on the primary side of the air filter F and the flow velocity of air flowing into the measuring tube 10, the flow velocity ratio and the flow velocity within a predetermined time are maintained. The total amount of alkaline substances in the air sent to the air filter F within the predetermined time is determined from the ratio of the flow rate of the air flown into the measurement tube 10 and the flow rate of the air sent to the air filter F. Therefore, the remaining service life of the air filter F can be easily and surely determined.

When the detection device M is installed so that the air on the secondary side of the air filter F flows into the measuring tube 10 (FIG. 3), the air is sent through the air filter F. It is possible to easily determine whether or not the air filter F is functioning properly by monitoring the change over time in the amount of the alkaline substance contained in the air.
By keeping the flow velocity of the air on the secondary side of the air filter F and the flow velocity of the air flowing into the measurement tube 10 at a constant velocity or maintaining a predetermined flow velocity ratio, From the ratio of the flow rate of the air flowing into the measuring pipe 10 to the flow rate of the air sent through the air filter F, the air guided into the ventilation pipe P and fed into the space S within a predetermined time. The total amount of alkaline substance in can be determined.

When the detection devices M are installed on the primary side and the secondary side of the air filter F (FIG. 4), the air sent to the air filter F and the air sent through the air filter F are sent. It is possible to determine the change with time in the amount of alkaline substances contained in these air and the total amount thereof both in the stored air.

Here, the reactant 20 may have any structure as long as it is discolored in response to an alkaline substance contained in the air and the discoloration can be visually recognized from the outside of the measuring tube 10. The reactant 20 can be configured by supporting an acidic substance and a reagent that changes color by the reaction of the acidic substance and the alkaline substance on the carrier formed on the granules.

Further, in the flow rate adjusting means 30, the reactant 20 enclosed in the measuring tube 10 in a predetermined amount gradually changes color with time from the air inflow side 10a of the measuring tube 10 toward the outflow side 10b. As described above, any configuration may be used as long as the flow rate of the air flowing into the measurement tube 10 is maintained. For example, the suction amount of the air pump 32 or the like connected to the outflow side 10b of the measurement tube 10 may be adjusted by a needle valve. The flow velocity adjusting means 30 can be configured by appropriately adjusting the flow rate using 31 or the like. More specifically, the reactant 20
According to the adsorbed amount of the alkaline substance, a predetermined amount of the reactant 20 enclosed in the measuring tube 10 is gradually changed in color from the inflow side 10a of the air of the measuring tube 10 toward the outflow side 10b. In addition, the flow velocity of the air can be determined, and the flow velocity adjusting means 30 is configured to always maintain the determined flow velocity.

Further, in this embodiment, the measuring tube 10 is provided with a breathable partition member 10c on the outflow side 10b and the inflow side 10a, and the reactant 20 is enclosed between the partition members 10c. In addition to the above, the measurement tube 10 that constitutes the detection device M has a translucent property that allows at least a part of the enclosed reactant 20 to be visible from the outside, and thus has a granular shape. The reactant 20 can be stably positioned in the measuring tube 10, and air can be passed through the measuring tube 10 through the partition member 10c and the enclosed reactant 20.
Further, the discoloration of the reactant 20 due to the passage of such air can be easily visually recognized from the outside.

Further, the detection device M according to this embodiment
Can be configured by at least including the measuring tube 10 in which the reactant 20 is enclosed and the flow velocity adjusting means 30, and thus has a feature that it can be configured relatively easily and can be provided at low cost.

In the present specification, the secondary side of the air filter F refers to the air filter F in the air passage P in which the air filter F is installed and the space S in which the air passage P communicates. Both the space and the space S are meant.

The space S in which the air to be processed by the air filter F is required is a clean room for manufacturing electronic parts such as semiconductors and ICs, and various electronic parts manufacturing apparatuses installed in the clean room. It means all spaces S such as a space, a museum for displaying paintings, an exhibition space of a museum, etc., in which it is required to supply air from which alkaline substances have been removed.

Next, a more specific embodiment of the present invention shown in FIGS. 1 to 6 will be described in detail.

Here, FIG. 1 is an explanatory view showing an outline of the detection device M according to this embodiment. 2 shows an example in which the detection device M is provided in the ventilation path P on the primary side of the air filter F, and FIG. 3 shows the detection device M is provided in the ventilation path P on the secondary side of the air filter F. 4 further shows an example in which the detection device M is provided in the ventilation passage P on the primary side and the ventilation passage P on the secondary side of the air filter F, the detection device M, the air filter F, and the air filter F. The space S required to obtain the air to be treated is shown by a block. (It should be noted that in the figure, the symbol Pa indicates the air passage on the air feeding side, the symbol Pe indicates the air passage on the air outlet side, and the symbol Pr indicates the above-mentioned (This is a ventilation path for circulating a part of the air sent out from the space S to the ventilation path Pa on the sending side.)

Further, FIG. 5 shows a concrete constitutional example of the detecting device M in a perspective state, and FIG. 6 shows that the measuring tube 10 constituting the detecting device M is supplied with ammonia gas of a predetermined concentration. The inflow time and the discoloration length of the reactant 20 enclosed in the measurement tube 10 from the inflow side 10a to the outflow side 10b of the measurement tube 10 when the contained air is continuously flowed in at a predetermined flow rate. It is a graph which shows the relationship of.

The detection device M according to this embodiment includes a measuring tube 10 in which a granular reactant 20 which changes color by reacting with an alkaline substance contained in the air guided to the ventilation path P, and The flow rate adjusting means 30 for maintaining the flow rate of the air flowing into the measurement pipe 10 connected to the ventilation path P at one end is provided.

The measuring tube 10 is configured as a cylindrical thin tube in this embodiment, and more specifically, a glass tube having an inner diameter of 6 mm, which is usually called a column, is used.

The measuring tube 10 is provided with the reactant 20 enclosed in the measuring tube 10 on one end side and the other end side.
The partitioning materials 10c are fitted in each. In this embodiment, the partition member 10c is a disc-shaped sponge member having air permeability. In this embodiment, the distance between the pair of partition members 10c and 10c is set to 80 mm.
The above-mentioned granular reactant 20 is enclosed between c.

In the present embodiment, the reactant 20 enclosed in the measuring tube 10 reacts with the granular substance on the acidic substance, and the acidic substance reacts with the alkaline substance in the air. It is configured to support a reagent that changes color.

More specifically, in this embodiment, the carrier is roughly crushed by a crusher, and
Silica gel that has been classified by sieving in the range of 42 mm to 1.0 mm is used.

Further, 0.01N sulfuric acid is used as the acidic substance. (0.01N sulfuric acid is 10 liters of water obtained by adding 5 g of H ₂ SO ₄ (special grade 98%) to 1 liter.
It means 0 ml added with water to make 1 liter. )

As the reagent, 0.25 g of methyl orange dissolved in 250 ml of water and 0.25 g of blumphenol blue dissolved in 250 ml of ethyl alcohol (95%) were used. There is.

Then, the first reactant constituted by mixing 50 ml of the 0.01N sulfuric acid with 5 ml of the methyl orange solution and 50 g of the carrier and drying the mixture at a temperature of 105 ° C to 110 ° C. And the above 0.0
50 ml of 1N sulfuric acid to which 5 ml of Bloomphenol blue solution was added was mixed with 50 g of the above-mentioned carrier and dried at a temperature of 105 ° C. to 110 ° C. to form a second reaction product in a ratio of 1: 1. 2g of mixed in proportion
Is the reactant 20 enclosed in the measuring tube 10 as described above.

When the first reactant and the second reactant are mixed to form the reactant 20, the reactant 20 is
When viewed with the outside of the measuring tube 10 with the naked eye, it is reddish orange, and it is observed that the color changes to yellow blue due to a reaction with an alkaline substance. It is recognized that the boundary where the discolored range and the undiscolored range contact each other becomes easier to recognize with the naked eye than in the case where the reactant 20 is composed of only one of the bodies.

The measuring tube 10 constructed as described above is arranged on the surface of the operation panel 40 constituting the detecting device M so that one end is the inflow side 10a of the air and the other end is the outflow side 10b of the air. Fixed. That is, in this embodiment, one end of the measurement pipe 10 is connected to a pipe, a tube, or the like connected to the ventilation path P that supplies air to the space S where the air to be processed by the air filter F is required. A pipe, a tube, and the like, which are connected in an airtight state and are connected to the other end in an airtight state, are connected to the air pump 32. Therefore, by driving the air pump 32, the air in the ventilation path P flows into the measurement pipe 10 with one side of the measurement pipe 10 being the inflow side 10a and the other side being the outflow side 10b. There is. In addition, in order to easily measure the length of the discoloration range of the reactant 20 enclosed in the measurement tube 10, in this embodiment, the side of the measurement tube 10 in the operation panel 40 is provided. A measure 41 is provided.

In this embodiment, a needle valve 31 for adjusting the intake amount of the air pump 32 is provided on the exhaust side of the air pump 32. By operating the needle valve 31, the measuring pipe is The configuration is such that the flow velocity of the air flowing into 10 can be adjusted. That is, in this embodiment, by operating the needle valve 31, the flow rate of the air flowing into the measuring tube 10 is changed so that the reactant 20 enclosed in the measuring tube 10 is It is possible to constantly maintain a flow velocity that gradually changes color from the inflow side 10a toward the outflow side 10b, and at the same time, the flow velocity of the air flowing into the measurement pipe 10 and the flow velocity of the air flowing through the ventilation path P Can be kept constant, or the flow velocity of the air flowing into the measuring pipe 10 and the flow velocity of the air flowing through the ventilation path P can be kept at a predetermined flow velocity ratio at all times.

In this embodiment, an appropriate flow meter 42 is provided on the operation panel 40 and the knob 42a of the flow meter 42 is operated so that the flow velocity of the air can be easily adjusted. The needle valve 31 is closed and opened.

On the operation panel 40, the measuring tube 1
A timer 44 is provided to start integration of time by turning on the drive switch 43 of the air pump 32 so that the time of inflow of air into 0 can be easily measured.

Since the detection device M according to this embodiment has the above-mentioned structure, the air in the air passage P is introduced into the measuring pipe 10 at a predetermined flow rate by driving the air pump 32. And the reactant 20 enclosed in the measuring tube 10 according to the concentration of the alkaline substance contained in the air, particularly the alkaline substance.
Is gradually changed in color from the air inflow side 10a of the measurement tube 10 toward the outflow side 10b. That is,
The alkaline substance contained in the air reacts with the acidic substance carried by the reactant 20, so that a predetermined flow rate is maintained in the measuring tube 10, that is, by injecting air at a predetermined flow velocity, Thereby lowering the acidity of the reactant 20, causing discoloration of the reagent, that is, discoloration of the reactant 20. Moreover, since the amount of the alkaline substance that can be adsorbed by the group of the reaction bodies 20 within the unit length of the reaction body 20 and thus the unit length of the measurement tube 10 in the vertical direction is substantially constant, After the acidic substance of the reactant 20 located on the air inflow side 10a of the measuring pipe 10 has completely reacted with the alkaline substance, the measuring pipe 1
The alkaline substance in the air flowing into 0 is adsorbed by the next-ranked reactant 20 located on the outflow side 10b of the air with respect to the reactant 20 having finished the reaction, and the next-ranked reactant 20 is removed. Discolor. In this way, the reactant 20 enclosed in the measuring tube 10 is gradually discolored with time from the air inflow side 10a of the measuring tube 10 toward the outflow side 10b.

FIG. 6 shows a result of flowing air containing 30 ppb of ammonia gas into the measuring tube 10 at 1.4 liters per minute.

The reactant 2 enclosed in the measuring tube 10
0 indicates that the color gradually changes from the inflow side 10a of the measuring tube 10 with time. When the concentration of the alkaline substance contained in the air is constant, the It is recognized that the length of the color change range of the reactant 20 enclosed in the measurement tube 10 from the air inflow side 10a to the air outflow side 10b of the measurement tube 10 is proportional.

From the above, according to the detecting device M of this embodiment, the measuring tube 10 is provided after a predetermined time.
By measuring the length of the color change range of the reactant 20, the change in the concentration of the alkaline substance contained in the inflowing air can be easily determined from the relationship between the time and the length of the color change range. .

Further, from the length (L) of the color change range and the adsorption amount (V) of the alkaline substance per unit length of the reactant 20, it is easily contained in the air flowing into the measuring tube 10. It is possible to determine the total amount of alkaline substance that is present. (L × V = total amount of alkaline substance)

The length (L) of the discoloration range, the time (Hr) during which the air is flown into the measuring tube 10, and the adsorption amount (V) of the alkaline substance per unit length of the reactant 20. And the flow rate (R) of the air flowing into the measurement tube 10 per unit time, the average concentration of the alkaline substance contained in the air can be easily determined.
((L × V) ÷ (Hr × R) = average concentration of alkaline substance)

Further, based on the average concentration of the alkaline substance calculated in this way, from the flow rate of the air guided to the air passage P during the time when the air is flowing into the measuring pipe 10, the air filter is obtained. When the detection device M is installed on the primary side of F, the total amount of alkaline substances contained in the air sent to the air filter F, and when the detection device M is installed on the secondary side of the air filter F The total amount of alkaline substances contained in the air sent through the air filter F can be determined.

When it is necessary to determine the total amount of a specific substance contained in the alkaline substance contained in the air flowing into the measuring tube 10, for example, the total amount of ammonia gas, the color change as described above. It is possible to accurately determine the total amount of the ammonia gas by taking out the reactant 20 thus prepared from the measuring tube 10, separating ammonia by a distillation method, and quantifying the ammonia by an ion chromatography method or the like. It

[0053]

As described above, when the air guided in the air passage P is introduced into the measuring tube 10 which constitutes the detecting device M according to the present invention as described above, the measuring tube 10 is affected by the alkaline substance contained in the air. The reactant 20 enclosed in 10 is gradually discolored over time from the air inflow side 10a to the air outflow side 10b. As a result, according to the detection device M of the present invention, the time during which the air is flown into the measurement tube 10 and the air inflow side 10a to the outflow side of the reactant 20 enclosed in the measurement tube 10 are measured. 1
From the length of the color change area toward 0b, the color change length of the reactant 20 per unit time can be easily recognized. Then, by comparing the discoloration length of the reactant 20 per unit time with the length of the discoloration area of the reactant 20 enclosed in the measuring tube 10 thereafter, the alkaline substance contained in the air is compared. It is possible to easily determine the increase / decrease in time.

In addition, from the inflow side 10a of the air to the outflow side 1 of the reactant 20 enclosed in the measuring tube 10.
From the length of the color change area toward 0b and the amount of the alkaline substance required when the reactant 20 changes color for a predetermined length, the alkaline substance contained in the air flowing into the measuring tube 10 is measured. Can be easily determined.

Thus, according to the detecting device M of the present invention, when the detecting device M is installed so that the air on the primary side of the air filter F flows into the measuring tube 10, the air filter F is installed. It is possible to monitor changes in the amount of alkaline substances contained in the air sent to the chamber with time, and to determine the flow rate of the air on the primary side of the air filter F and the flow rate of the air flowing into the measuring tube 10. By keeping the speed constant, the ratio of the flow rate of the air flowing into the measuring tube 10 and the flow rate of the air sent to the air filter F within the predetermined time is determined within the predetermined time. The total amount of alkaline substances in the air sent to F can be determined, and the remaining service life of the air filter F can be determined easily and reliably. Further, by keeping a predetermined flow velocity ratio between the flow velocity of air on the primary side of the air filter F and the flow velocity of air flowing into the measuring tube 10, the flow velocity ratio and the flow velocity within a predetermined time are maintained. The total amount of alkaline substances in the air sent to the air filter F within the predetermined time is determined from the ratio of the flow rate of the air flown into the measurement tube 10 and the flow rate of the air sent to the air filter F. Therefore, the remaining service life of the air filter F can be easily and surely determined.

When the detection device M is installed so that the air on the secondary side of the air filter F flows into the measuring tube 10, it is included in the air sent through the air filter F. It is possible to easily determine whether or not the air filter F is properly functioning by monitoring the change over time in the amount of the alkaline substance, and to measure the flow velocity of the air on the secondary side of the air filter F. And the measuring tube 10
The flow rate of the air flowing into the measuring pipe 10 is kept constant at a constant flow velocity or a predetermined flow velocity ratio, so that the flow rate of the air flowing into the measuring tube 10 and the air filter F within a predetermined time period can be controlled. From the ratio of the flow rates of the air sent through, it is possible to determine the total amount of the alkaline substance in the air that is guided into the ventilation pipe P and sent into the space S within the predetermined time.

When the detecting devices M are installed on the primary side and the secondary side of the air filter F, respectively, the air sent into the air filter F and the air sent through the air filter F are It is possible to determine the change in the amount of the alkaline substances contained in these air with time in both of them and their total amount.

Further, in the detecting device M according to the present invention, the measuring pipe 10 is provided with a breathable partition member 10c on the outflow side 10b and the inflow side 10a, and the reactant 20 is enclosed between the partition members 10c. In addition to the above, the measurement tube 10 that constitutes the detection device M has a translucent property that allows at least a part of the enclosed reactant 20 to be visually recognized from the outside, and thus has a granular shape. The reactant 20 can be stably positioned in the measuring tube 10, and air can be passed through the measuring tube 10 through the partition member 10c and the enclosed reactant 20. The discoloration of the reactant 20 that accompanies the passage can be easily visually recognized from the outside.

Further, since the detection device M according to the present invention can be constructed by at least including the measuring tube 10 in which the reactant 20 is enclosed and the flow velocity adjusting means 30, it can be constructed relatively easily and at a low cost. It has the features that can be provided to

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a detection device M.

FIG. 2 is an explanatory diagram showing an installation example of a detection device M.

FIG. 3 is an explanatory diagram showing an installation example of a detection device M.

FIG. 4 is an explanatory diagram showing an installation example of a detection device M.

FIG. 5 is a perspective view of a configuration example of a detection device.

FIG. 6 shows the inflow time and the reactants enclosed in the measuring tube 10 when air containing a predetermined concentration of ammonia gas is continuously flown into the measuring tube 10 of the detector M. 20 is a graph showing the relationship with the discoloration length from the inflow side 10a to the outflow side 10b of the measurement tube 10 in FIG.

[Explanation of symbols]

 F Air filter S Space P Ventilation path M Detector 10 Measuring tube 10a Inflow side 10b Outflow side 10c Partition material 20 Reactor 30 Flow velocity adjusting means

Claims (1)

[Claims] 1. A primary side, a secondary side, or a primary side and a secondary side of an air filter, which is installed in an air passage for supplying air to a space where air to be treated by an air filter is required, A detection device for detecting an alkaline substance contained in guided air, wherein the detection device is a granular reactant that changes color by reacting with an alkaline substance contained in the air guided to the air passage, One end is the inflow side of the air and the other end is the outflow side of the air, and an permeable partition member is provided on the outflow side and the inflow side, and the reactant is enclosed between the partition members. The measuring tube has a light-transmitting property such that at least a part of the enclosed reactant is visible from the outside, and one end of the measuring tube communicates with the ventilation path. Yes, the measuring tube A flow rate adjusting means for maintaining the flow rate of the air flowing into the measurement tube is provided so that the enclosed reactants gradually change color over time from the air inflow side to the outflow side of the measurement tube. A detection device characterized by being provided.