JPH05201452A - Liquid entering preventive device - Google Patents

Abstract

PURPOSE:To prevent a liquid entering by a simple structure by encapsulating a fiber, which swells when it absorbs a liquid, in the passage, for the subject device to prevent the entry of a liquid into the passage of a gas which is automatically closed. CONSTITUTION:A fiber (water-absorbent fiber) 24, which absorbs water, is encapsulated in an encapsulating part 23, which is a space being formed by casings 21, 22. Also, ribs 25, 26, which prevent the water-absorbent fiber 24 from protruding from the encapsulating part 23, are integrally formed on the casings 21, 22. The water-absorbent fiber 24 consists of a fiber main body and a macromolecular substance which adheres to the fiber main body, and the macromolecular substance is impregnated in the fiber main body or may be provided in such a manner that the macromolecular substance forms a film for the fiber main body. The title liquid entering preventive device which is substituted in such a manner is attached to, e.g. the suction port of a liquid collecting container, and when a liquid enters the container, the fiber 24 swells and eliminates gaps in the fiber 24, and provides a closed condition.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conventional water stop device when a liquid is injected into a container and it is necessary to automatically stop the liquid injection when the container is filled with a predetermined amount of liquid. The present invention relates to a liquid intrusion prevention device used instead of.

[0002]

2. Description of the Related Art When injecting a liquid into a container, it is necessary to automatically stop the injection when the liquid is filled in the container. As such a stopping means, a float type water shutoff valve can be mentioned. FIG. 8 shows an example of a float type water shutoff valve, and FIG. 9 shows a liquid collection container using the float type water shutoff valve of FIG. In the float type water shutoff valve 8, a float cage 2 is housed inside a frame body 1, and a seal material 3 such as soft urethane foam is inserted in the float cage 2. Frame 1
Is fitted to the exhaust pipe 5 of the container so that the air in the container can be sucked or exhausted from the exhaust port 6. In such a float-type water shut-off valve 8, the float basket 2 rises in response to the rise of the liquid level 7, and finally the sealing material 3 blocks the exhaust port 6 of the exhaust pipe 5, so that the container 10 is transferred to the container 10. Stop liquid injection. In addition,
In FIG. 9, 9 is an injection pipe.

However, in the float type water shutoff valve 8, when the liquid injection speed is high or a large amount of bubbles are generated, the float basket 2 does not rise according to the liquid level 7 or the top of the bubbles,
Since the sealing material 3 cannot seal the exhaust port 6, the excessively injected liquid flows out through the exhaust port 6. Further, when a solid suspended matter is contained in the liquid, this suspended matter is sandwiched between the seal material 3 and the sealing surface of the exhaust port 6 to form a gap, so that the exhaust port 6 may be completely blocked. Can not. Further, when mist or liquid droplets are generated, they may invade the exhaust port 6.

[0004]

Even when bubbles, droplets, etc. are generated, or solid suspended matter is present in the liquid,
In order to prevent the invasion of these exhaust pipes 5, the present inventors have proposed a liquid intrusion prevention device as shown in FIG.
Invented is a granular polymer substance 11 that absorbs a liquid and swells, and is sandwiched by porous supports 12 and 13 having pores through which the polymer substance 11 cannot pass but gas can pass.

The liquid intrusion prevention device having such a structure is used by being attached to a liquid collection container as shown in FIG. 4, for example. In this liquid collecting container, when suction is performed through the suction pipe 16 connected to a suction pump or the like, the container body 1
A negative pressure is generated in the inside of the nozzle 4, and the liquid is injected from the injection pipe 15.
The liquid intrusion prevention device 20 includes the suction port 17 of the lid 18 of the container.
Installed between the suction tube 16 and the suction tube 16, and the container body 1
4 is filled with the liquid and the liquid surface 19 is the liquid intrusion prevention device 20.
When it reaches, the polymer substance 11 absorbs the liquid and swells, and closes the hole of the porous support 12 on the suction port 17 side to stop the suction.

However, if this liquid intrusion prevention device is used in a highly volatile liquid injection or in a high humidity condition such as in the rainy season, the polymer substance 11 will not vaporize or vapor before the inside of the container is filled with the liquid. Since the tendency of absorbing and swelling to eliminate the gap between the polymer substances 11 becomes large, the suction function may be deteriorated and the suction stop function may be activated.
In such a case, the original function of the liquid collection container cannot be fully exhibited.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to prevent the deterioration of the suction function due to the swelling of a polymer substance under high humidity, but to bring it into contact with a droplet. On the other hand, it is to provide a liquid intrusion prevention device that immediately swells and stops suction.

[0008]

The liquid intrusion prevention device of the present invention is a liquid intrusion prevention device which automatically closes a passage when a liquid intrudes into the gas passage. It is enclosed in. As the fiber, a fiber made of a fiber body and a polymer substance that swells when adhering to the fiber body and absorbing a liquid; a fiber made of a polymer substance that swells when absorbing a liquid; or a combination thereof is used. These fibers may be encapsulated not only as a single fiber but also as a cloth.

The fibers are sealed in such an amount that the gap between the fibers is not extinguished by the vapor, but is extinguished by the contact with the liquid passing through the passage. The encapsulation amount may be adjusted to trap contaminants in the gas.

[0010]

In the liquid intrusion prevention device of the present invention, the fibers swell when absorbing the liquid, so that the gap between the fibers becomes small and disappears. Under the condition that the liquid reaches the liquid intrusion prevention device such as the rise of the liquid level, the swelling of the fibers causes the gap between the fibers to disappear, that is, the clogging occurs, and the infiltration of the liquid and gas is stopped. On the other hand, under high humidity, the fibers do not swell to such an extent that the gaps between the fibers disappear, so that the fibers do not become clogged.

Therefore, although the liquid injection is not stopped before the liquid is filled in the container together with the high-humidity gas, it is immediately clogged with the contact with the droplet such as the rise of the liquid level. The liquid and gas are prevented from entering the suction pump and the like by stopping the invasion of the liquid and gas.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an embodiment of the structure of the liquid intrusion prevention device of the present invention. In FIG. 1, a fiber (hereinafter referred to as a water-absorbent fiber) 24 that swells when absorbing water is enclosed in a space formed by casings 21 and 22 (hereinafter referred to as an enclosure 23) in a compressed state. In FIG. 1, 25 and 26 are
The ribs are integrally formed with the casings 21 and 22 so that the water-absorbent fibers 24 do not overflow into the passage due to suction or the like.

The water absorbing fibers 24 are composed of a fiber body and a polymer substance attached to the fiber body. The attachment mode is not particularly limited, and examples thereof include the case of being adhered to the surface of the fiber body, the case of being impregnated into the inside of the fiber body, or the case where a polymer substance forms a coating film of the fiber body. As the fiber body, synthetic fibers such as acrylic fiber, nylon fiber, polyester fiber, polyethylene fiber, polypropylene fiber, polyvinyl chloride fiber and polyvinyl acetate are used. The size is appropriately selected depending on the use location of the liquid intrusion prevention device, the purpose, etc., but the length is preferably about 10 mm or more and the thickness is preferably about 2.6 to 10 denier.

As the polymer substance attached to the fiber body,
A polymer substance that absorbs water and swells (hereinafter referred to as a water-absorbing polymer) is used. Examples of the water-absorbing polymer include sodium polyacrylate, a graft copolymer of starch and polyacrylic acid, a saponification product of a copolymer of vinyl acetate and methyl acrylate, and a copolymer of vinyl acetate and maleic anhydride. Examples thereof include saponified products of polymers and saponified products of copolymers of isobutylene and maleic anhydride.

The water-absorbent fiber having the above structure is
It changes as shown in FIG. 5 due to the contact with the liquid in the sealed portion 23. FIG. 5A shows a state before liquid absorption, and FIG. 5B shows a state after liquid absorption. As a result of the water-absorbent fibers 24 (particularly the water-absorbent polymer 31 attached to the fiber main body 30) absorbing water and swelling, the gaps between the water-absorbing fibers 24 become smaller and disappear.

The amount and the density of the water-absorbent fibers 24 enclosed in the enclosing portion 23 are not so large that the gap between the fibers is reduced even if it swells under high humidity, causing clogging, but it does not come into contact with liquid or bubbles. An amount and a density that prevent the invasion of a gas-dispersed liquid, such as, are preferable. The swelling degree or the swelling speed of the water absorbent fibers 24 varies depending on the type, the amount of the water absorbent fibers 24, the density, etc. of the water absorbent fibers 24. The pressure of the liquid that can be stopped depends on the water retention pressure of each water-absorbing polymer and the strength of the casing.

When the liquid intrusion prevention device having such a structure is attached to the suction port 17 of the liquid collection container as shown in FIG. 4 and the liquid is injected, the water absorbing fibers 24 in the device rises due to the liquid injection. The surface 19 and generated bubbles and the like absorb water and swell, and the gaps between the water-absorbent fibers 24 disappear to create a clogged state, so that suction is stopped. Further, in the liquid intrusion prevention device of the present embodiment, by changing the amount of the water-absorbent fibers 24 enclosed and adjusting the size of the gap between the fibers, a gas mixed with contaminants such as dust and bacteria is passed. In some cases, a function of filtering contaminants can be added.

Further, in the liquid intrusion prevention device having the above structure, the water absorbent fiber 24 is compressed and sealed in the casing 22 forming the recess of the enclosing portion 23, and then the casing 21 forming the lid portion of the enclosing portion 23 is joined. Since it can be manufactured by such a method, it is easier to manufacture than a structure in which a polymer material is sandwiched between porous supports. In the embodiments of the present invention, the water-absorbing polymer was used as the polymer substance, and the case where the liquid was water was described. However, the liquid intrusion prevention device having the configuration of the present invention can It can be applied to various liquids by appropriately selecting the type of polymer substance to be attached.

Further, in the present embodiment, the fiber having the structure described in claim 2 was used as the fiber to be enclosed, but the present invention is not limited to this, and is made of a polymer substance which absorbs a liquid and swells. A fiber (corresponding to claim 3) or a fiber made of a polymer substance that absorbs a liquid and swells.
A combination with the fiber described in (corresponding to claim 4)
May be used. Furthermore, the fibers may be enclosed in the form of a cloth such as a non-woven fabric or a woven fabric.

Specific Examples Example 1 As the water absorbent fiber, Lansil-F (trade name) manufactured by Toyobo Co., Ltd. having a size of 5 denier and a fiber length of 51 mm was used. This water-absorbent fiber is a fiber whose main body is acrylic fiber and whose main body is coated with sodium polyacrylate which is a water-absorbing polymer. This fiber is 4% in an atmosphere of 20 ° C and 85% relative humidity.
Even if left for 8 hours, the weight increases by about 50% (swells about 1.2 times as the fiber diameter) (see Fig. 6), but instantaneously (about 1 second) under the condition of being in direct contact with water. Then, 13 ml of water is absorbed per 1 g of the fiber (swelling about 3.7 times as the fiber diameter) (see FIG. 7).

Such a water-absorbent fiber is used as a sealing portion (diameter 15 mm, height 15) of a liquid intrusion prevention device as shown in FIG.
(mm cylindrical shape), the minimum amount of water that can be stopped is 0.038 g / cm ³ as a density and a porosity of 9
This corresponds to 6.8%. In addition, the maximum amount of filling that does not cause pressure loss that may cause trouble even when used under high humidity is:
This corresponds to a density of 0.227 g / cm ³ and a porosity of 80.6%. In addition, these filling amounts are such that the porosities after injecting water at 40 ° C. for 30 minutes are 94.2% and 78.8, respectively.
% Is the amount.

A water-absorbent fiber having the above characteristics was prepared with a basis weight of 2000 g / m ² , a density of 0.139 g / cm ² ,
It was enclosed so that the porosity was 88.7%. This enclosed amount is such that the weight becomes about 14 times after 1 second of water absorption and the gap between the fibers disappears. Then, as a liquid intrusion prevention device, 600 mmHg (8160 mmHg
The water of ₂ O) immediately absorbed water and swelled to show a water-stopping effect.

Next, with respect to this liquid intrusion prevention device, the suction pressure is 400 mmHg, 600 mmHg, 760 mmHg.
The pressure loss when aspirating with was measured. Table 1 shows the pressure loss at each suction pressure and the pressure loss of the liquid collection container itself.
The pressure loss when the liquid intrusion prevention device is not attached is also shown in Table 1 as a blank. In addition, this liquid intrusion prevention device was attached to the liquid collection container shown in FIG. 4, water at 40 ° C. was injected for 30 minutes at a suction pressure of 400 mmHg, and the change in pressure loss during this time was measured to investigate the effect on water vapor. .. The change in pressure loss is shown in FIG. Early and 30
The porosity (%) after the minute injection is also shown in FIG.

Comparative Example 1; In the conventional liquid intrusion prevention apparatus shown in FIG. 2, a polypropylene non-woven fabric having a thickness of 0.1 mm was used as the porous support 12 on the inflow side (the side connected to the container lid), and the outflow side. As the porous support 13 (on the side connected to the suction pump), urethane foam having a thickness of 4.0 mm was used. The polymer substance 11 has a particle size of 150 to 10
00 μm sodium polyacrylate was used. This water-absorbent polymer increased about 80% in weight (swelled about 1.2 times in particle size) when left in an atmosphere of 85% relative humidity at 20 ° C. for 48 hours, under the condition of being in direct contact with water. In that case, it swells due to water absorption and swells about 4 times as the particle size.

Such a liquid intrusion prevention device has a length of 600 m
Immediately absorbed by water of mHg (8160 mmH ₂ O), it swelled and exhibited a water blocking effect. Next, with respect to this liquid intrusion prevention device, a suction pressure of 400 m is obtained in the same manner as in the first embodiment.
The pressure loss when sucking at mHg, 600 mmHg, and 760 mmHg, and the influence on water vapor were measured.
The results are shown in Table 1 and FIG.

Comparative Example 2; Liquid having the same structure as Comparative Example 1 except that a non-woven fabric made of nylon 6,6 having a thickness of 0.6 mm and subjected to a hydrophobic treatment was used as the porous support 12 on the inflow side. Created an intrusion prevention device. The liquid intrusion prevention device thus prepared was similar to Comparative Example 1 except that 600 mmHg (816
Immediately absorbed by water of 0 mmH ₂ O), it swelled and exhibited a water-stopping effect.

Using this liquid intrusion prevention device, Example 1
Similar to, suction pressure 400mmHg, 600mmH
g, the pressure loss when suctioned at 760 mmHg, and the effect on water vapor were measured. The results are shown in Table 1 and FIG.
Shown in.

Example 2; A gas containing dust was added to the liquid intrusion prevention device prepared in Example 1 at 4 l / min, 1.5-
The dust removal capability of the liquid intrusion prevention device was examined by allowing the liquid to pass through at a rate of 2.5 kgf / cm ² and measuring the rate of dust in the gas after passing. The dust removal rate is shown in Table 2 in correspondence with the particle size of the dust.

Example 3 The dust removing ability was examined in the same manner as in Example 2 except that the water absorbing fiber was changed to Lanseal-F having 2.6 denier and a fiber length of 38 mm. The results are shown in Table 2.

[Evaluation result]

[0031]

[Table 1]

As can be seen from Table 1, the liquid intrusion prevention device of Example 1 is comparative example 1 at any suction pressure.
Also, the pressure loss was smaller than that of the liquid intrusion prevention device of Comparative Example 2. Further, as can be seen from FIG. 1, in the liquid intrusion prevention device of the example, the pressure loss hardly changed even when water at 40 ° C. was continuously injected for 30 minutes, and the influence of water vapor on the water blocking effect of the device was recognized. There wasn't.

On the other hand, although the water-absorbent polymer substance alone has the same water-absorption swelling behavior when directly contacted with moisture and water, it is used as a liquid intrusion prevention device (Comparative Example 1 and Comparative Example 1). In Example 2), the pressure loss increased due to clogging not only with the rise of the liquid level but also with moisture (see FIG. 3). Even if the porous support on the inflow side was subjected to the hydrophobic treatment (Comparative Example 2), there was no great difference compared to the case where it was not treated (Comparative Example 1).

[0034]

[Table 2] As can be seen from Table 2, 90% or more of particles of 0.3 μm or more could be removed by any of the liquid intrusion prevention devices of Examples 2 and 3.

[0035]

As described above, the liquid intrusion prevention device of the present invention has a small loss of suction pressure for injecting liquid, and
Under high humidity, the swelling of the fibers enclosed in the device does not cause clogging and increase in pressure loss. Therefore, even when it is used in high humidity such as the rainy season, or when vapor or humidity is sucked in, it does not become clogged, and when the container is fully filled with liquid, that is, the liquid level becomes a liquid intrusion prevention device. When it arrives, it stops the liquid injection and exerts a water blocking effect.

Further, according to the structure of the liquid intrusion prevention device of the present invention, both ends of the enclosing portion are fixed without fixing the water absorbing fiber to the enclosing portion by the sandwiching structure by the porous support unlike the conventional case. Since it suffices to provide ribs on the substrate, the manufacturing is easy and the manufacturing cost is low. further,
In the liquid intrusion prevention device of the present invention, the function of capturing contaminants such as dust and bacteria can be imparted by adjusting the amount of fibers enclosed.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a configuration of a liquid intrusion prevention device according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing a configuration of a liquid intrusion prevention device of a comparative example.

FIG. 3 is a graph showing the influence of water vapor on the liquid intrusion prevention device of a specific example.

FIG. 4 is a diagram showing a specific usage example of the liquid intrusion prevention device.

FIG. 5 is a diagram for explaining the behavior of the fiber encapsulated in the present invention with respect to a liquid.

FIG. 6 is a graph showing changes in moisture-absorbing fibers used in specific examples with respect to humidity.

FIG. 7 is a graph showing changes when the water-absorbent fiber used in a specific example comes into contact with a liquid.

FIG. 8 is a diagram showing a configuration of a float type water shutoff valve which is an example of a conventional liquid intrusion prevention device.

9 is a diagram showing a configuration of a liquid collection container to which the float type water shutoff valve shown in FIG. 8 is attached.

[Explanation of symbols]

 21 Casing 22 Casing 23 Encapsulation 24 Water-absorbent fiber 30 Fiber body 31 Polymeric substance 32 Gap between fibers

[Procedure amendment]

[Submission date] March 12, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Full text

[Correction method] Change

[Correction content]

[Document name] Statement

Patent application title: Liquid intrusion prevention device

[Claims]

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conventional water stop device when a liquid is injected into a container and it is necessary to automatically stop the liquid injection when the container is filled with a predetermined amount of liquid. The present invention relates to a liquid intrusion prevention device used instead of.

[0002]

2. Description of the Related Art When injecting a liquid into a container, it is necessary to automatically stop the injection when the liquid is filled in the container. As such a stopping means, a float type water shutoff valve can be mentioned. FIG. 8 shows an example of a float type water shutoff valve, and FIG. 9 shows a liquid collection container using the float type water shutoff valve of FIG. In the float type water shutoff valve 8, a float cage 2 is housed inside a frame body 1, and a seal material 3 such as soft urethane foam is inserted in the float cage 2. Frame 1
Is fitted to the exhaust pipe 5 of the container so that the air in the container can be sucked or exhausted from the exhaust port 6. In such a float-type water shut-off valve 8, the float basket 2 rises in response to the rise of the liquid level 7, and finally the sealing material 3 blocks the exhaust port 6 of the exhaust pipe 5, so that the container 10 is transferred to the container 10. Stop liquid injection. In addition,
In FIG. 9, 9 is an injection pipe.

However, in the float type water shutoff valve 8, when the liquid injection speed is high or a large amount of bubbles are generated, the float basket 2 does not rise according to the liquid level 7 or the top of the bubbles,
Since the sealing material 3 cannot seal the exhaust port 6, the excessively injected liquid flows out through the exhaust port 6. Further, when a solid suspended matter is contained in the liquid, this suspended matter is sandwiched between the seal material 3 and the sealing surface of the exhaust port 6 to form a gap, so that the exhaust port 6 may be completely blocked. Can not. Further, when mist or liquid droplets are generated, they may invade the exhaust port 6.

[0004]

Even when bubbles, droplets, etc. are generated, or solid suspended matter is present in the liquid,
In order to prevent the invasion of these exhaust pipes 5, the present inventors have proposed a liquid intrusion prevention device as shown in FIG.
Invented is a granular polymer substance 11 that absorbs a liquid and swells, and is sandwiched by porous supports 12 and 13 having pores through which the polymer substance 11 cannot pass but gas can pass.

The liquid intrusion prevention device having such a structure is used by being attached to a liquid collection container as shown in FIG. 4, for example. In this liquid collecting container, when suction is performed through the suction pipe 16 connected to a suction pump or the like, the container body 1
A negative pressure is generated in the inside of the nozzle 4, and the liquid is injected from the injection pipe 15.
The liquid intrusion prevention device 20 includes the suction port 17 of the lid 18 of the container.
Installed between the suction tube 16 and the suction tube 16, and the container body 1
4 is filled with the liquid and the liquid surface 19 is the liquid intrusion prevention device 20.
When it reaches, the polymer substance 11 absorbs the liquid and swells, and closes the hole of the porous support 12 on the suction port 17 side to stop the suction.

However, if this liquid intrusion prevention device is used in a highly volatile liquid injection or in a high humidity condition such as in the rainy season, the polymer substance 11 will not vaporize or vapor before the inside of the container is filled with the liquid. Since the tendency of absorbing and swelling to eliminate the gap between the polymer substances 11 becomes large, the suction function may be deteriorated and the suction stop function may be activated.
In such a case, the original function of the liquid collection container cannot be fully exhibited.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to prevent the deterioration of the suction function due to the swelling of a polymer substance under high humidity, but to bring it into contact with a droplet. On the other hand, it is to provide a liquid intrusion prevention device that immediately swells and stops suction.

[0008]

The liquid intrusion prevention device of the present invention is a liquid intrusion prevention device which automatically closes a passage when a liquid intrudes into the gas passage. It is enclosed in. As the fiber, a fiber made of a fiber body and a polymer substance that swells when adhering to the fiber body and absorbing a liquid; a fiber made of a polymer substance that swells when absorbing a liquid; or a combination thereof is used. These fibers may be encapsulated not only as a single fiber but also as a cloth.

The fibers are sealed in such an amount that the gap between the fibers is not extinguished by the vapor, but is extinguished by the contact with the liquid passing through the passage. The encapsulation amount may be adjusted to trap contaminants in the gas.

[0010]

In the liquid intrusion prevention device of the present invention, the fibers swell when absorbing the liquid, so that the gap between the fibers becomes small and disappears. Under the condition that the liquid reaches the liquid intrusion prevention device such as the rise of the liquid level, the swelling of the fibers causes the gap between the fibers to disappear, that is, the clogging occurs, and the infiltration of the liquid and gas is stopped. On the other hand, under high humidity, the fibers do not swell to such an extent that the gaps between the fibers disappear, so that the fibers do not become clogged.

Therefore, although the liquid injection is not stopped before the liquid is filled in the container together with the high-humidity gas, it is immediately clogged with the contact with the droplet such as the rise of the liquid level. By stopping the invasion of the liquid and the gas, the liquid is prevented from invading the downstream piping, the suction pump and the like.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an embodiment of the structure of the liquid intrusion prevention device of the present invention. In FIG. 1, a fiber (hereinafter referred to as a water-absorbent fiber) 24 that swells when absorbing water is enclosed in a space formed by casings 21 and 22 (hereinafter referred to as an enclosure 23) in a compressed state. In FIG. 1, 25 and 26 are
The ribs are integrally formed with the casings 21 and 22 so that the water-absorbent fibers 24 do not overflow into the passage due to suction or the like.

The water absorbing fibers 24 are composed of a fiber body and a polymer substance attached to the fiber body. The attachment mode is not particularly limited, and examples thereof include the case of being adhered to the surface of the fiber body, the case of being impregnated into the inside of the fiber body, or the case where a polymer substance forms a coating film of the fiber body.

As the fiber body, synthetic fibers such as acrylic fiber, nylon fiber, polyester fiber, polyethylene fiber, polypropylene fiber, polyvinyl chloride fiber and polyvinyl acetate are used. The size is appropriately selected depending on the use location of the liquid intrusion prevention device, the purpose, etc., but the length is preferably about 10 mm or more and the thickness is preferably about 2.6 to 10 denier. As the polymer substance attached to the fiber body, a polymer substance that absorbs water and swells (hereinafter referred to as a water-absorbing polymer) is used. Examples of the water-absorbing polymer include sodium polyacrylate, a graft copolymer of starch and polyacrylic acid, a saponification product of a copolymer of vinyl acetate and methyl acrylate, and a copolymer of vinyl acetate and maleic anhydride. Examples thereof include saponified products of polymers and saponified products of copolymers of isobutylene and maleic anhydride.

The water-absorbent fiber having the above structure is
It changes as shown in FIG. 5 due to the contact with the liquid in the sealed portion 23. FIG. 5A shows a state before liquid absorption, and FIG. 5B shows a state after liquid absorption. As a result of the water-absorbent fibers 24 (particularly the water-absorbent polymer 31 attached to the fiber main body 30) absorbing water and swelling, the gaps between the water-absorbing fibers 24 become smaller and disappear.

The amount and the density of the water-absorbent fibers 24 enclosed in the enclosing portion 23 are not so large that the gap between the fibers is reduced even if it swells under high humidity, causing clogging, but it does not come into contact with liquid or bubbles. An amount and a density that prevent the invasion of a gas-dispersed liquid, such as, are preferable. The swelling degree or the swelling speed of the water absorbent fibers 24 varies depending on the type, the amount of the water absorbent fibers 24, the density, etc. of the water absorbent fibers 24. The pressure of the liquid that can be stopped depends on the water retention pressure of each water-absorbing polymer and the strength of the casing.

When the liquid intrusion prevention device having such a structure is attached to the suction port 17 of the liquid collection container as shown in FIG. 4 and the liquid is injected, the water absorbing fibers 24 in the device rises due to the liquid injection. The surface 19 and generated bubbles and the like absorb water and swell, and the gaps between the water-absorbent fibers 24 disappear to create a clogged state, so that suction is stopped. Further, in the liquid intrusion prevention device of the present embodiment, by changing the amount of the water-absorbent fibers 24 enclosed and adjusting the size of the gap between the fibers, a gas mixed with contaminants such as dust and bacteria is passed. In some cases, a function of filtering contaminants can be added.

Further, in the liquid intrusion prevention device having the above structure, the water absorbent fiber 24 is compressed and sealed in the casing 22 forming the recess of the enclosing portion 23, and then the casing 21 forming the lid portion of the enclosing portion 23 is joined. Since it can be manufactured by such a method, it is easier to manufacture than a structure in which a polymer material is sandwiched between porous supports. In the present invention embodiment, using a water-absorbing polymer as the polymer material, but the liquid has been described for the case of water, the liquid intrusion preventing device having the onset bright configuration, type of fiber, or the fiber body It can be applied to various liquids by appropriately selecting the type of polymer substance to be attached.

Further, in the present embodiment, the fiber having the structure described in claim 2 was used as the fiber to be enclosed, but the present invention is not limited to this, and is made of a polymer substance which absorbs a liquid and swells. A fiber (corresponding to claim 3) or a fiber made of a polymer substance that absorbs a liquid and swells.
A combination with the fiber described in (corresponding to claim 4)
May be used. Furthermore, the fibers may be enclosed in the form of a cloth such as a non-woven fabric or a woven fabric.

Specific Examples Example 1 As the water absorbent fiber, Lansil-F (trade name) manufactured by Toyobo Co., Ltd. having a size of 5 denier and a fiber length of 51 mm was used. This water-absorbent fiber is a fiber whose main body is acrylic fiber and whose main body is coated with sodium polyacrylate which is a water-absorbing polymer. This fiber is 4% in an atmosphere of 20 ° C and 85% relative humidity.
Even if left for 8 hours, the weight increases by about 50% (swells about 1.2 times as the fiber diameter) (see Fig. 6), but instantaneously (about 1 second) under the condition of being in direct contact with water. Then, 13 ml of water is absorbed per 1 g of the fiber (swelling about 3.7 times as the fiber diameter) (see FIG. 7).

Such a water-absorbent fiber is used as a sealing portion (diameter 15 mm, height 15) of a liquid intrusion prevention device as shown in FIG.
(mm cylindrical shape), the minimum amount of water that can be stopped is 0.038 g / cm ³ as a density and a porosity of 9
This corresponds to 6.8%. In addition, the maximum amount of filling that does not cause pressure loss that may cause trouble even when used under high humidity is:
This corresponds to a density of 0.227 g / cm ³ and a porosity of 80.6%. In addition, these filling amounts are such that the porosities after injecting water at 40 ° C. for 30 minutes are 94.2% and 78.8, respectively.
% Is the amount.

A water-absorbent fiber having the above characteristics was prepared with a basis weight of 2000 g / m ² , a density of 0.139 g / cm ² ,
It was enclosed so that the porosity was 88.7%. This enclosed amount is such that the weight becomes about 14 times after 1 second of water absorption and the gap between the fibers disappears. As a liquid intrusion prevention device, positive pressure or negative pressure of 600 mmHg (81
Immediately absorbed by water of 60 mmH ₂ O), it swelled and showed a water-stopping effect.

Next, this liquid intrusion preventing device, suction pressure - 400mmHg, - 600mmHg, - 760m
The pressure loss when suctioned at mHg was measured. Table 1 shows the pressure loss at each suction pressure and the pressure loss of the liquid collection container itself. The pressure loss when the liquid intrusion prevention device is not attached is also shown in Table 1 as a blank. Also, attached to the liquid collection container showing a liquid intrusion preventing device in Figure 4, suction pressure - at 400 mmHg, a 40 ° C. water was injected 30 minutes, by measuring the change in the meantime in the pressure loss, examined the effect to water vapor It was The change in pressure loss is shown in FIG. The porosity (%) at the initial stage and after pouring for 30 minutes is also shown in FIG.

Comparative Example 1; In the conventional liquid intrusion prevention apparatus shown in FIG. 2, a polypropylene non-woven fabric having a thickness of 0.1 mm was used as the porous support 12 on the inflow side (the side connected to the container lid), and the outflow side. As the porous support 13 (on the side connected to the suction pump), urethane foam having a thickness of 4.0 mm was used. The polymer substance 11 has a particle size of 150 to 10
00 μm sodium polyacrylate was used. This water-absorbent polymer increased about 80% in weight (swelled about 1.2 times in particle size) when left in an atmosphere of 85% relative humidity at 20 ° C. for 48 hours, under the condition of being in direct contact with water. In that case, it swells due to water absorption and swells about 4 times as the particle size.

[0025] Such liquid intrusion prevention devices, - 600
Immediately absorbed by water of mmHg (8160 mmH ₂ O), it swelled and showed a water stopping effect. Next, this liquid intrusion preventing device, in the same manner as in Example 1, the suction pressure - 40
0mmHg, - 600mmHg, - the pressure loss when sucked by 760 mmHg, and to determine the effect against water vapor. The results are shown in Table 1 and FIG.

Comparative Example 2; Liquid having the same structure as Comparative Example 1 except that a non-woven fabric made of nylon 6,6 having a thickness of 0.6 mm and subjected to a hydrophobic treatment was used as the porous support 12 on the inflow side. Created an intrusion prevention device. Liquid intrusion preventing device is created, as in Comparative Example 1, - 600 mm Hg (81
Immediately absorbed by water of 60 mmH ₂ O), it swelled and showed a water-stopping effect.

Using this liquid intrusion prevention device, Example 1
In the same manner as the suction pressure - 400 mmHg, - 600 mm
Hg, - the pressure loss when sucked by 760 mmHg, and to determine the effect against water vapor. The results are shown in Table 1 and FIG.

Example 2; A gas containing dust was added to the liquid intrusion prevention device prepared in Example 1 at 4 l / min, 1.5-
The dust removal capability of the liquid intrusion prevention device was examined by allowing the liquid to pass through at a rate of 2.5 kgf / cm ² and measuring the rate of dust in the gas after passing. The dust removal rate is shown in Table 2 in correspondence with the particle size of the dust.

Example 3 The dust removing ability was examined in the same manner as in Example 2 except that the water absorbing fiber was changed to Lanseal-F having 2.6 denier and a fiber length of 38 mm. The results are shown in Table 2.

[Evaluation result]

[0031]

[Table 1]

As can be seen from Table 1, the liquid intrusion prevention device of Example 1 is comparative example 1 at any suction pressure.
Also, the pressure loss was smaller than that of the liquid intrusion prevention device of Comparative Example 2. Further, as can be seen from FIG. 1, in the liquid intrusion prevention device of the example, the pressure loss hardly changed even when water at 40 ° C. was continuously injected for 30 minutes, and the influence of water vapor on the water blocking effect of the device was recognized. There wasn't.

On the other hand, although the water-absorbent polymer substance alone has the same water-absorption swelling behavior when directly contacted with moisture and water, it is used as a liquid intrusion prevention device (Comparative Example 1 and Comparative Example 1). In Example 2), the pressure loss increased due to clogging not only with the rise of the liquid level but also with moisture (see FIG. 3). Even if the porous support on the inflow side was subjected to the hydrophobic treatment (Comparative Example 2), there was no great difference compared to the case where it was not treated (Comparative Example 1).

[0034]

[Table 2] As can be seen from Table 2, 90% or more of particles of 0.3 μm or more could be removed by any of the liquid intrusion prevention devices of Examples 2 and 3.

[0035]

As described above, the liquid intrusion prevention device of the present invention has a small loss of suction pressure for injecting liquid, and
Under high humidity, the swelling of the fibers enclosed in the device does not cause clogging and increase in pressure loss. Therefore, even when it is used in high humidity such as the rainy season, or when vapor or humidity is sucked in, it does not become clogged, and when the container is fully filled with liquid, that is, the liquid level becomes a liquid intrusion prevention device. When it arrives, it stops the liquid injection and exerts a water blocking effect.

Further, according to the structure of the liquid intrusion prevention device of the present invention, both ends of the enclosing portion are fixed without fixing the water absorbing fiber to the enclosing portion by the sandwiching structure by the porous support unlike the conventional case. Since it suffices to provide ribs on the substrate, the manufacturing is easy and the manufacturing cost is low. further,
In the liquid intrusion prevention device of the present invention, the function of capturing contaminants such as dust and bacteria can be imparted by adjusting the amount of fibers enclosed.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a configuration of a liquid intrusion prevention device according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing a configuration of a liquid intrusion prevention device of a comparative example.

FIG. 3 is a graph showing the influence of water vapor on the liquid intrusion prevention device of a specific example.

FIG. 4 is a diagram showing a specific usage example of the liquid intrusion prevention device.

FIG. 5 is a diagram for explaining the behavior of the fiber encapsulated in the present invention with respect to a liquid.

FIG. 6 is a graph showing changes in moisture-absorbing fibers used in specific examples with respect to humidity.

FIG. 7 is a graph showing changes when the water-absorbent fiber used in a specific example comes into contact with a liquid.

FIG. 8 is a diagram showing a configuration of a float type water shutoff valve which is an example of a conventional liquid intrusion prevention device.

9 is a diagram showing a configuration of a liquid collection container to which the float type water shutoff valve shown in FIG. 8 is attached.

[Explanation of Codes] 21 Casing 22 Casing 23 Enclosing Part 24 Water-Absorbing Fiber 30 Fiber Body 31 Polymeric Material 32 Gap between Fibers

Claims (7)

[Claims] 1. A liquid intrusion prevention device for automatically closing a passage to prevent a liquid from entering the passage of a gas, wherein fibers swelling when absorbing the liquid are enclosed in the passage. Liquid intrusion prevention device. 2. The liquid intrusion prevention device according to claim 1, wherein the fibers are composed of a fiber body and a polymer substance attached to the fiber body, and the polymer substance swells when absorbing a liquid. 3. The liquid intrusion prevention device according to claim 1, wherein the fiber is made of a polymer substance that swells when absorbing a liquid. 4. The liquid intrusion prevention device according to claim 1, wherein the fiber is a combination of the fiber according to claim 2 and the fiber according to claim 3. 5. The fibers are encapsulated in such an amount that the gap between the fibers does not disappear under high humidity, but disappears by contact with a liquid passing through the passage. 5. The liquid intrusion prevention device according to any one of 4 to 4. 6. The fiber according to any one of claims 1 to 5, wherein the amount of the encapsulated fibers is an amount that traps contaminants in the gas and prevents the contaminants from entering the passage. The liquid intrusion prevention device as described in 1. 7. The liquid intrusion prevention device according to claim 1, wherein the fiber is cloth-shaped and enclosed.