JP5250244B2 - Gas collector - Google Patents

Description

  The present invention relates to a gas collection device that continuously collects a gas to be collected contained in the atmosphere over a predetermined collection period.

  Conventionally, establishments that handle chemical substances and their administrative agencies, etc. measure the concentration at appropriate sampling points for chemical substances that are discharged into the atmosphere from those establishments and that are highly toxic or interested. By doing so, it is expected that the standard value or voluntary management target value will be observed, and that information will be disclosed to local residents as necessary.

  However, there are many cases where there are no power supply facilities at appropriate measurement points in the vicinity of the office, and the above toxicity and interest are high over a convincing long period (for example, one week) based on scientific support at such points. Realizing a device that can continuously collect and measure chemical substances so that it can be carried around and that there is no loss due to reaction between the time of collection and the analysis after collection. It has not been realized due to the limit of gas collection by the vacuum vessel and specific capacity of the battery.

  Due to the above circumstances, the corporate social responsibility of monitoring the air emitted from the company's offices and the safety confirmation of residents of local governments are often limited to the minimum scope of activities. Currently.

The gas collection device disclosed in Patent Document 1 is provided with a collection impinger on the intake side of a portable air pump, and in order to absorb the measurement gas into the solution and analyze it, the volume of the collected air is a gas valve. It aims at simplification of an apparatus by devising so that it may correspond to the volume which became full.
Therefore, the volume of air that can be measured in one measurement is at most several liters in the case of a portable type. In addition, it is assumed to be a slightly high concentration gas measurement such as indoor formaldehyde measurement. The measurement of the height of 150 (cm) and the weather resistance and reliability for long-term measurement were out of the field of view.
Japanese Patent Laid-Open No. 10-148603

  In addition, when there is a power supply facility that supplies a 100 (V) AC power supply, although continuous gas collection over a long period of time is possible, there is a problem in that the installation location is limited. Although the disclosed gas collection device is not limited by the installation location, a sample volume of 10 liters or less cannot capture the most compelling sample volume necessary for long-term gas measurement over a week or more. .

Furthermore, air (gas) must be collected at a predetermined height (usually 150 cm), but in the case described in Patent Document 1, air is collected at a predetermined height. Therefore, it is impossible to solve problems such as wall adsorption and bending of the tube when air is brought from the air intake port to the impinger.
Furthermore, in the gas collection device disclosed in Patent Document 1, there is no description of airtightness and tipping prevention measures necessary for outdoor use for a week, and further up to an outdoor measurement point. There is no description about the transportation method.

  Furthermore, in addition to what is disclosed in Patent Document 1, the conventional gas collection device generally has a structure in which operation switches and meters are exposed to the outside. In addition to insufficient protection, it is difficult to ensure robustness that can withstand continuous use for more than one week, and there are also disadvantages that labor is required for maintenance.

  Accordingly, an object of the present invention is to provide a gas collection device that can continuously collect a specific collection target gas contained in the atmosphere over a long period of time even in a place where there is no power supply facility.

  The gas collection device according to the present invention for solving the above problems includes a dehumidification pipe for reducing the humidity of the taken-in air to a required value, and different collection target gases contained in the air flowing out from the dehumidification pipe And a plurality of collection columns for collecting each of the gas, and a gas collection unit in which an air intake unit for taking in the air at a predetermined height position is erected outside the sealed case, A single diaphragm pump for simultaneously sucking the plurality of columns, and a DC-AC conversion circuit that performs inverter control for converting direct current output from the following direct-current power supply unit into alternating current having a required frequency; A suction control unit that drives and controls the diaphragm pump so that the air suction operation is continuously performed over a predetermined collection period, and power is supplied to the suction control unit and the diaphragm pump. That a DC power supply unit is housed in a sealed case, and is characterized by performing the suction operation of the air taken in from outside the sealed casing.

According to the present invention, since the air pump is driven and controlled so as to continuously perform the air suction operation through the gas collection unit over a predetermined collection period, even in a place where there is no power supply facility, A specific gas to be collected contained therein can be continuously collected over a predetermined collection period.
For example, the DC-AC conversion circuit converts the current into several tens (V) of alternating current and drives the air pump to realize a significant reduction in power consumption. As a result, a small battery of 10 (kg) or less can be obtained. Even if it is used, the collecting operation for one week or more can be continued.
The dehumidifying tube can reduce the humidity of the taken-in air to a required value. Thereby, even if it is a substance with low boiling points, such as a dichloromethane, the fall of adsorption capacity can be prevented and sufficient collection can be performed.

  The best mode for carrying out the present invention will be described below with reference to the drawings. FIG. 1 shows a schematic configuration of a gas collection device according to an embodiment of the present invention, in which (A) is a plan view thereof, and (B) is a front sectional view showing a part thereof in section. 2 is a block diagram showing a connection relationship of the gas collection device shown in FIG. 1, and FIG. 3 is an enlarged view of a portion indicated by an encircling line I in FIG.

  A gas collection device A according to an embodiment of the present invention has an air intake part B standing outside the sealed case 10 and an air pump C, a suction control part D, a power supply part E, and a gas collection part F. It is configured to be accommodated in the sealed case 10 and to perform the suction operation of the air taken in from the outside of the case 10, and the details thereof are as follows.

The sealed case 10 has a structure in which a lid 12 for opening and closing the opening 11a is attached to the case body 11, and is made of a material having good weather resistance such as aluminum.
The case main body 11 has a capacity capable of accommodating an air pump C, a suction control unit D, a power supply unit E, and a gas collecting unit F, which will be described in detail later, and the side walls 14-around the bottom wall 13 that is rectangular in plan view. 17 is formed by surrounding.

The lid 12 is attached to the upper edge 15a of the peripheral wall 15 so as to be freely opened and closed, and seals the opening 11a of the case body 11. “Sealing” means that the sealing can be performed in a watertight and almost airtight manner, and the structure has no adverse effect of wind and rain and dust at least during a predetermined collection period.
Note that the case 10 does not have to be a sealed structure as long as it does not have an adverse effect of wind and rain or dust at least during a predetermined collection period.
The “predetermined collection period” in the present embodiment assumes a period of about one week, but includes a period of several days or one week or more.

  The case main body 11 has a pair of holding projections 21 which are paired with each other and slidably hold the partition plate 20 in the vertical direction a at the center position of the side walls 15 and 17 where the two storage chambers α and β are formed. 21 is disposed.

  Among the storage chambers α and β, the storage chamber α stores the air pump C, the suction control unit D, and the power supply unit E, and the storage chamber β stores the gas collection unit F, and at the time of transportation. The decomposed air intake B is accommodated.

A circular through hole 16a for inserting the atmospheric intake tube T is formed on the center bottom side of the side wall 16, and a tube guide member 30 is mounted in the through hole 16a.
The tube guide member 30 includes a cylindrical guide member 31 fitted in the through hole 16 a and a lid member 32.

  The guide member 31 has an inner end 31a formed in the case main body 11 and an outer end 31b formed so as to protrude to the outside of the case main body 11, and a lid is provided on the outer peripheral wall of the outer end 31b. A groove portion (not shown) in which the member 32 can be screwed is formed.

The lid member 32 is formed by forming a collar portion 32b on the outer peripheral edge of the substrate 32a over the entire circumference, and an insertion hole 32c for inserting the atmosphere intake tube T is opened at the center of the substrate 32a.
When the lid member 32 is screwed into the guide member 31 with the air intake tube T inserted through the guide member 31, the air intake tube T can be held in an airtight and watertight manner.

  On the outer surface of the side wall 16, supports 40 and 41 for erecting and supporting an atmospheric intake B, which will be described in detail later, are fixed at a required interval that can hold the hollow support pipe 50 described below upright.

  The air intake portion B is configured such that an air intake tube T in which an air intake port Ta is opened at the upper end portion is housed in a metal hollow support tube 50 that is detachably attached to the sealing case 10. In the present embodiment, the air intake port Ta is bent slightly downward as shown in FIG. 1 to prevent rainwater or the like from entering.

  The air intake tube T in the present embodiment is formed of a fluorine-based resin that is difficult to adsorb gas. However, the present invention is not limited to this, and for example, when gas adsorption does not become a problem or the type of gas to be collected Depending on the case, it may be formed of another resin.

Although the fluororesin tube has poor workability due to lack of flexibility, in this embodiment, a series of seamless connections from the air intake port Ta at the upper end of the tube to the attachment / detachment port Tb at the base end. Is adopted.
Thereby, the attachment / detachment location of the tube is limited to only the attachment / detachment location with the dehumidifying tube 60 that forms a part of the gas collection part F, thereby reducing troubles due to the attachment / detachment of the tube. Further, by inserting the tube through the hollow support tube 50, the air intake port Ta of the tube T is held at a certain height position 1.5 (m), and the portion exposed to the field is minimized. ing.

  In addition, by forming spiral continuous irregularities or bellows-shaped irregularities on the outer surface of the fluororesin tube, for example, the tube can be easily inserted into the hollow support tube 50 at the same time, and at the same time, the dehumidifying tube 60 The workability of the attaching / detaching operation can be improved.

  When the proximal end portion of the hollow support tube 50 is supported by the supports 40 and 41, the height H from the ground surface G of the air intake port Ta of the air intake tube T becomes 1.5 (m). In this embodiment, it is configured by connecting three divided pipes up and down.

  At the attachment / detachment port Tb of the atmosphere intake tube T that forms a part of the atmosphere intake portion B, a gas collection portion F for collecting the gas to be collected contained in the atmosphere introduced through the atmosphere intake portion B; A suction control unit D that sucks air through the gas collecting unit F is connected in order from the upstream side to the downstream side. In other words, they are connected in order from the upstream side to the downstream side along the air intake path.

FIG. 4 is a detailed explanatory view showing details of the partition plate 20 and the gas collection unit F mounted and disposed on the partition plate 20.
If a relative humidity of 70% or more continues for a long time, such as in the rain, a substance having a low boiling point such as dichloromethane is reduced in adsorption capacity and cannot be sufficiently collected. Therefore, the gas collection unit F is configured as follows.

  The gas collection unit F is for adsorbing and collecting the dehumidifying pipe 60 for reducing the humidity of the taken-in air to a required value and the different collection target gases contained in the air flowing out from the dehumidifying pipe 60. It consists of two collection columns 61 and 62, and is mounted on the surface 20a of the partition plate 20 that faces the storage chamber β.

The dehumidifying tube 60 contains a dehumidifying agent in an elongated circular tube body 63 made of glass having a required capacity. An inflow port 64 is provided at one end (upper end) of the circular tube 63, and the like. Outflow ports 65 for allowing the air after dehumidification to flow out are respectively formed at the end portions (lower end portions).
A branching tool 66 for branching the dehumidified air to the collection columns 61 and 62 is connected to the outlet 65, and the branching tool 66 and the collection columns 61 and 62 are connected to the connection tubes 67 and 62. 68 is disposed.

  Adsorbent silica gels, molecular sieves, calcium carbonate, calcium chloride, and phosphorus pentoxide are known as dehumidifiers, but when these are used, it is clear that a part of atmospheric gas is lost by adsorption or absorption. Thus, in this embodiment, magnesium perchlorate is used.

One collection column 61 contains an activated carbon-based adsorbent that adsorbs volatile organic compounds in a circular tube having a required capacity, and the other collection column 62 is a circle having a required capacity. The tube contains a cartridge filled with a scavenger containing dinitrophenyl hydrazine hydrochloride (DNPH) on the surface of silica.
In addition, as a collection agent, it is not restricted to the above-mentioned thing, You may combine another collection agent as needed.

  With the above configuration, unstable substances can be simultaneously collected from activated carbon such as aldehydes from general volatile organic compounds. In other words, different types of collection target gases can be collected simultaneously.

By the way, it is necessary to take out the collecting agent after the above-described predetermined collection period and replace the dehumidifying agent. However, since the gas collecting unit F is mounted on the partition plate 20, they are put together. So that it can be easily handled.
Further, the partition plate 20 can be taken out of the case body 11 by removing the air intake tube T from the dehumidifying tube 60. As a result, the collection work of the collection columns 61 and 62 and the replacement work of the dehumidifying tube 60 can be easily performed, and troubles such as improved workability and erroneous operation can be prevented.

The air pump C is a so-called diaphragm pump. In the present embodiment, the suction operation for the two collection columns 61 and 62 is performed by a single pump.
Specifically, the two diaphragms are driven by a single motor (both not shown), and for each diaphragm, in other words, for each collection column, the exhaust ports 71, 72 and the intake ports 73, 74 is provided.
In this embodiment, the suction operation with respect to the two collection columns 61 and 62 is performed by one pump, thereby realizing a significant reduction in power consumption.

The capillary 80 is used to increase or decrease the suction flow rate of the atmosphere, and is formed with a length and an inner diameter corresponding to the predetermined collection period described above. FIG. 5 is an explanatory diagram for explaining the principle of increasing / decreasing the suction flow rate of the atmosphere with the capillary. Table 1 (A) shows the relationship between the pump pressure and the length L of the capillary, and (B) shows the relationship between the flow rate F and the length L of the capillary. In addition, the relationship between the capillary and the flow rate shown in (B) is the one at 100 V operation.

As shown in FIG. 5, the length of the capillary 80 is L (cm), the inner diameter d (mm), the linear flow velocity u of the flowing air, and the pressure difference ΔP between the front and rear of the capillary 80 (between both end faces). The following relational expression is established. Note that μ _G and ρ _G are the viscosity and density of air, respectively.
_{ΔP = (3ρ G μ2) /} 4 + (32μ G Lu) / d 2
Here, when the collected flow rate is determined, the linear flow velocity u of the flowing air is a function of the inner diameter d, and thus the above equation is a function of the length L and the inner diameter d of the capillary 80.
As is apparent from Table 1, the length L and the inner diameter d of the capillary 80 are set so that the amount of gas to be collected adsorbed on the collection columns 61 and 62 is optimal during the predetermined collection period. To do.
In the present embodiment, a plurality of types of capillaries having lengths and inner diameters corresponding to different predetermined collection periods are prepared, and the discharge side of the air pump selectively corresponding to each collection period, In this embodiment, the exhaust port is detachably attached.
Although not shown in the present embodiment, the same effect can be obtained even if it is detachably mounted on the suction side of the air pump.

流量Ｆは、キャピラリの長さＬと内径ｄ、及びポンプ性能を示すΔＰ、流体、すなわち空気の物性μ_Ｇ、ρ_Ｇから求められるので、他の条件が一定ならば、長さＬと内径ｄの組み合わせの異なるキャピラリに交換して使用することで所定流量が実現する。
本発明の大気捕集装置運転において必要な流量は２００（ｍｌ／ｍｉｎ）以下であり、使用するポンプは差圧が３０，０００（Ｐａ）で十分である。従って、仮に上限となる２００（ｍｌ／ｍｉｎ）を流すとして、常温常圧における空気の物性及びポンプ差圧６０，０００Ｐａ、表１の式からキャピラリ長５０（ｍ）とすると、内径は１．２×１０^−３（ｍ）となる。
キャピラリ長は５０（ｍ）を最大として任意であるから、長さの短縮に応じて内径は小さくなる。したがって、本装置におけるキャピラリは、長さ５０（ｍ）以下、内径は１．４×１０^−３（ｍ）以下のものを使用すればよい。
キャピラリの材質としては、ガラス、ステンレス、フッ素系樹脂等のプラスチック、又はガスクロマトグラフィ等で使用されるキャピラリカラムを選択できる。
また、キャピラリを装置に組み込むときには、巻回して収納することも可能であり、この場合収納スペースを有効に活用できる。
長さについては、例えば巻回収納することことができるステンレスやフッ素系樹脂、キャピラリカラム等を考えた場合、容易に形状を変化させることにより例えば全長５０（ｍ）のものであっても装置内に組み込むことができる。また、ガラスカラム等であれば１（ｃｍ）程度まで短くすることも可能である。
数１を用いて設計したときの理論的流量と実測値は表１（Ｂ）に示すように非常によい一致を見ている。
また、本装置の流量安定性は表２に示すとおりであり、一週間捕集で３（％）未満の流量低下に収まっている。

About the conditions for flow control, it can design using the formula shown in Formula 1.

The flow rate F is obtained from the capillary length L and the inner diameter d, ΔP indicating the pump performance, and the physical properties of the fluid, that is, air, μ _G , ρ _G. Therefore, if other conditions are constant, the length L and the inner diameter d A predetermined flow rate is realized by replacing the capillaries with different combinations.
The required flow rate in the operation of the air collecting apparatus of the present invention is 200 (ml / min) or less, and a differential pressure of 30,000 (Pa) is sufficient for the pump used. Accordingly, assuming that the upper limit of 200 (ml / min) is flowed, assuming that the physical properties of air at normal temperature and normal pressure and the pump differential pressure of 60,000 Pa and the capillary length of 50 (m) from the equation in Table 1, the inner diameter is 1.2. × 10 ⁻³ (m).
Since the capillary length is arbitrary up to 50 (m), the inner diameter decreases as the length is shortened. Therefore, a capillary having a length of 50 (m) or less and an inner diameter of 1.4 × 10 ⁻³ (m) or less may be used in this apparatus.
As the material of the capillary, glass, stainless steel, plastic such as fluorine resin, or capillary column used in gas chromatography or the like can be selected.
Further, when the capillary is incorporated into the apparatus, it can be wound and stored, and in this case, the storage space can be used effectively.
Regarding the length, for example, when considering stainless steel, fluororesin, capillary column, etc. that can be wound and stored, the shape can be easily changed, for example, even if the length is 50 (m). Can be incorporated into. Moreover, if it is a glass column etc., it is also possible to shorten to about 1 (cm).
As shown in Table 1 (B), the theoretical flow rate and the actual measurement value when designed using Equation 1 are in very good agreement.
Further, the flow rate stability of the present apparatus is as shown in Table 2, and the flow rate is reduced to less than 3 (%) after one week of collection.

電圧は運転開始から穏やかに低下し、１週間で約１２（Ｖ）、２週間で約１１（Ｖ）になり、その後、１１（Ｖ）を下回った辺りから急速に低下し、４００時間弱で電圧が３（Ｖ）程度でエアポンプは停止した。よって、通常の鉛バッテリの性質から判断して、２００回程度は１週間捕集が可能であると推測される。 -Charging method and operation time The battery (power supply unit) was charged with GS BC-3A2-12VT, and charged until it was automatically stopped from full charge. The voltage at this time was about 13 (V).
Table 3 shows changes in voltage when the operation is started with an air pump to which an inverter and a capillary are added.

The voltage gradually decreases from the start of operation, reaches about 12 (V) in one week, and about 11 (V) in two weeks, and then rapidly decreases from below about 11 (V), and is less than 400 hours. The air pump stopped at a voltage of about 3 (V). Therefore, judging from the properties of a normal lead battery, it is estimated that about 200 times of collection can be performed for one week.

The suction control unit D has a DC-AC conversion circuit, and performs a function of converting direct current output from the power supply unit E into alternating current having a required frequency by an oscillation circuit (not shown), that is, by performing so-called inverter control. The rotation of the air pump C is increased or decreased (variable).
Specifically, a significant reduction in power consumption has been realized by converting the alternating current into several tens of volts (V) and driving the diaphragm pump, thereby using a small battery of 10 (kg) or less. However, the collecting operation for one week or more can be continued.
“Continuously performing the collecting operation” includes, for example, a collecting operation that is intermittent at regular time intervals in addition to the continuous collecting operation.
Instead of using a DC-AC conversion circuit and an AC pump, a DC voltage conversion circuit and an appropriate power saving DC pump may be used in combination.

In the present embodiment, a changeover switch (not shown) corresponding to two collection periods, ie, a collection period of about one week and a collection period of about two weeks, is provided so that it can be switched as necessary. However, it may be one corresponding to a predetermined collection period.
Note that measurements collected continuously for more than a week are not easily affected by climate change, etc., and it is possible to represent monitoring for the entire year by simply performing regular measurements several times a year. Therefore, it is possible to acquire data efficiently from the points of persuasiveness and cost effectiveness based on scientific support.

The power source E is a so-called Leadacid Battery, and is placed and fixed on the bottom wall 13 of the other storage chamber α in the case body 11 described above.
<Relationship between voltage and flow rate>
In the present embodiment, the DC battery of 12 (V) is subjected to voltage conversion, and is operated at about AC 40 (V). For this reason, it is considered that the basic performance of the air pump changes when the 100 (V) power supply is used. Therefore, changes in voltage and flow rate were confirmed.
When a capillary having an inner diameter of 0.18 (mm) and a length of 1 (cm) was attached during 100 V operation, the flow rate was 80 (ml / min). The flow rate during operation from 11.6 to 12.3 (V) was 48 (ml / min) with the same capillary.
This is considered to be a result of a decrease in ΔP in the relational expression between the flow rate and the capillary because the driving force against the resistance is reduced because the operating voltage is reduced to about 40 (V). On the other hand, no change in flow rate was observed in the range of 8.1 (V) to 12.3 (V). This is presumably because the output voltage from the inverter was stable.

  The suction control unit D described above is disposed on an impact buffering material 90 placed on the power supply unit E, and the air pump E is disposed on an impact cushioning material 91 placed on the suction control unit D.

In the present embodiment, sampling at a high point of 150 (cm) is realized at the time of collecting the gas to be collected, but a metal hollow support tube 50 having a circular cross section and low air resistance is used. And by designing the overall center of gravity to be as low as possible, consideration is given to prevent accidents and falls due to strong winds during installation.
In the present embodiment, the distance from the ground surface G to the center of gravity of the sealing case 10 and the distance from the ground surface G to the air intake port Ta are set to a ratio that is difficult to fall by the action of an external force based on an assumed wind. Specifically, it is set to about 1: 8, but it is more preferable to set it to a ratio higher than that.

An example is shown below.
Power source E: Weight 9 (kg) and center of gravity position is 9 (cm) from the ground surface G.
Sealing case 10: Width 43 (cm), depth 28 (cm), height 46 (cm), weight 4 (kg), and center of gravity 24 (cm) from the ground surface G.
Partition plate 20: 400 (g) and center of gravity 18 (cm).
Suction control unit D: 300 (g) and center of gravity height 28 (cm).
Air pump C: 600 (g) and the center of gravity height is 32 (cm).
Hollow support tube 50: 300 (g), center of gravity from surface G to 80 (cm).
When calculating the above embodiment, the total weight ignoring the weight of tubes such as the air intake tube T is 14.6 (kg), and the entire center of gravity is located at 16 (cm) from the installation surface. Realizes possible weight and position of center of gravity that is difficult to tip over.

The gas collection operation having the above-described configuration will be described.
The air intake part B, the air pump C, the suction control part D, the power supply part E, and the gas collection part F are transported to the measurement point in a state of being accommodated in the sealed case 10. As described above, since the total weight can be about 14.6 (kg), transportation can be easily performed.

  The hollow support tube 50 accommodated in the compartment β of the sealed case 10 is taken out and assembled, attached to the support devices 40 and 41 fixed to the side wall 16 of the case main body 11, and the air is taken into the hollow support tube 50. The tube T is inserted, and the attachment / detachment opening Tb is connected to the dehumidifying tube 60. Thereby, the preparation for gas collection is completed.

  Then, when a switch (not shown) of the suction control unit D is turned on, the collection operation is started. At this time, the air pump C is driven and controlled by the suction control unit D so as to continuously perform an air suction operation over a predetermined collection period.

  The air taken in by the suction force of the air pump C is guided to the dehumidifying pipe 60 through the air intake B and the moisture is removed, and then the gas to be collected is adsorbed and collected in the two collection columns 61 and 62. The

Further, the capillaries 80 and 80 installed on the exhaust side of the air pump C suck the air so that the amount of substances adsorbed on the collection columns 61 and 62 during the collection period becomes appropriate for the measurement. The flow rate is controlled.
Accordingly, even when measurement is performed with a single device while changing the collection period, the optimum sample amount can always be adsorbed and collected simply by replacing the capillary.

  Further, since the case body 11 is provided with the lid body 12, the partition plate 20 can be taken out and the battery E can be charged from above the case body 11. Further, since the lid 12 is facing downward, it is difficult for rain and dust to enter the inside of the case body 11, the atmosphere intake Ta is facing downward, and the opening is open when the lid 12 is closed. Together with the absence, it prevents moisture and dust from entering and reduces the maintenance burden for outdoor use.

  Next, another example of the capillary connection structure will be described with reference to FIG. FIG. 6 is an explanatory diagram showing a configuration in which a plurality of capillaries are connected to an exhaust port of an air pump via a switching device. In addition, about the thing equivalent to what was demonstrated in above-mentioned embodiment, the code | symbol same as them is attached | subjected and description is abbreviate | omitted.

  Capillaries 81 to 83 having lengths and inner diameters corresponding to different collection periods are connected to the exhaust ports 71 and 72 of the air pump C via switching units 90 to 92, respectively.

  In this configuration, one of the switching devices 90 to 92 of the capillaries 81 to 83 to be used may be opened and the other switching devices 90 to 92 may be closed without performing an operation of replacing the capillaries every collection period. .

FIG. 7 is a partially enlarged view corresponding to FIG. 3, showing an air intake tube according to another example and a tube connecting portion formed on the side wall.
The side wall 16 is formed with a tube connecting portion 110 for connecting the atmospheric intake tube 100 according to another example.
The tube connecting portion 110 includes an outer tube fitting portion 112 that protrudes outward with a through hole 111 formed through the inner and outer surfaces of the side wall 16 as a center, and an inner tube fitting portion 113 that protrudes inward.

  An air intake tube 100 according to another example includes an inner tube 101 that connects an outer end to the inner tube fitting portion 113 and an inner end to the dehumidifying tube 60, and a proximal end to the outer tube fitting portion 111. And an outer tube 102 having an air intake port 102a formed at the upper end.

  According to the atmosphere intake tube 100 and the tube connecting portion 110 configured as described above, the attaching / detaching operation of the inner tube 101 to the inner tube fitting portion 113 and the attaching / detaching operation of the outer tube 102 to the outer tube fitting portion 112 are separately performed. Since it can be performed, the work performed outside the sealed case 10 and the work performed inside can be separated, and the occurrence of troubles associated with the attachment and detachment of the collection columns 61 and 62 and the dehumidifying tube 60 can be further prevented. .

The present invention is not limited to the above-described embodiments, and the following modifications can be made.
In the above embodiment, the dehumidifying tubes are shared with the collection columns 61 and 62. However, a total of two dehumidifying tubes may be used exclusively for the collection columns 61 and 62. .

-In the above-mentioned embodiment, although the example which accommodated the gas collection part, the air pump, the suction control part, and the power supply part in the case was explained, in addition to those composition, the flow measurement part which measures the collection flow rate It may be incorporated.
Measuring the collected flow rate includes measuring only the instantaneous flow rate, only the integrated flow rate, and measuring both the instantaneous flow rate and the integrated flow rate.
Specifically, the flow rate measuring unit is disposed in the middle of the suction tube, for example, between the collection columns 61 and 62 and the air pump C shown in FIG. 1 in order to confirm the actual flow rate. It is not limited to.
The flow rate measuring unit is provided with a flow meter that can measure only the instantaneous flow rate, only the integrated flow rate, and both the instantaneous flow rate and the integrated flow rate, and this can be linked to the control unit.
It is also possible to integrate the pump, the flow rate measuring unit, and the control unit interlocked therewith.

In the above embodiment, an example is described in which a plurality of types of capillaries having lengths and inner diameters corresponding to different collection periods are selectively detachably attached to the discharge side of the air pump corresponding to each collection period. However, it may be detachably mounted on the suction side of the air pump.
Specifically, it may be disposed in a flow path 75 and 76 between the air pump C and the collection column 61 and 62 shown in FIG. 2, for example. The capillaries may be disposed on the discharge side and suction side of the air pump.

In the above embodiment, an example in which weather resistance is improved by adopting a sealing case made of aluminum has been described, but a known weather resistant paint is applied to the outer surface of the sealing case. May be.

BRIEF DESCRIPTION OF THE DRAWINGS The schematic structure of the gas collection apparatus which concerns on one Embodiment of this invention is shown, (A) is the top view, (B) is front sectional drawing which makes the one part a cross section. It is a block diagram which shows the connection relation of the gas collection apparatus shown in FIG. FIG. 2 is an enlarged view of a portion indicated by a surrounding line I in FIG. It is detailed explanatory drawing which shows the detail of a partition plate and the gas collection part mounted and arrange | positioned by this. It is explanatory drawing for demonstrating the principle which carries out increase / decrease adjustment of the attraction | suction flow volume of air | atmosphere with a capillary. It is explanatory drawing which shows the structure which connected the several capillary to the exhaust port of the air pump via the switch. It is the elements on larger scale equivalent to the said FIG. 3 which shows the tube for air | atmosphere intake concerning another example, and the tube connection part formed in the side wall.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Sealing case 50 Hollow support pipe 61, 62 Collection column 71, 72 Exhaust port 80 Capillary 110 Atmospheric intake tube B Atmospheric intake part C Air pump D Suction control part E Power supply part F Gas collection part T Atmospheric intake tube Ta Atmosphere Intake

Claims (4)

A dehumidifying tube to reduce the humidity of the air taken in to the required value;
A plurality of collection columns for adsorbing and collecting different gases to be collected contained in the atmosphere flowing out from the dehumidifying pipe, and an air intake section for taking in air at a predetermined height position A gas collecting part erected outside the sealed case ;
A single diaphragm pump for simultaneously aspirating the plurality of columns ;
It has a DC-AC conversion circuit that performs inverter control for converting direct current output from the following direct current power source into alternating current having a required frequency so as to continuously perform an air suction operation over a predetermined collection period. A suction control unit for driving and controlling the diaphragm pump ;
A gas collection device characterized in that the suction control unit and a direct current power source unit that supplies power to the diaphragm pump are housed in a sealed case, and the suction operation of the air taken from outside the sealed case is performed. The gas collection device according to claim 1, wherein the air intake section includes an air intake tube having an air intake opening formed at an upper end portion in a hollow support tube that is detachably mounted outside the sealed case. . The gas collection device according to claim 1 or 2, wherein a capillary for increasing or decreasing an air suction flow rate is provided for each collection column . Plural types of capillaries with lengths and inner diameters corresponding to different collection periods are selectively detachably attached to the suction side or the discharge side of a single diaphragm pump corresponding to each collection period. The gas collection device according to claim 3.

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