JPH0361096B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a humidifier that uses a natural evaporation method using hot air or the like, but has significantly improved humidification ability.

[Conventional technology]

From the perspective of energy conservation, modern living spaces are becoming more insulated and airtight, and more advanced air conditioning is required. Air conditioning elements include temperature control, humidity control, and control of harmful air components. Regarding temperature control, various heating and cooling methods have been put into practical use and are in a satisfactory state. However, there is still nothing completely satisfactory in terms of temperature control and control of harmful air components.

Regarding humidifiers, natural evaporation method, electric heating method,
There are water spray methods and ultrasonic methods, but the natural evaporation method has a small humidifying capacity, the electric heating method has high running costs, and the water spray method has low humidification efficiency and is bulky. Further, the ultrasonic method has drawbacks such as high initial cost and short life.

Therefore, we have repeatedly investigated ways to greatly improve the humidification capacity of a natural evaporation type humidifier, which has the lowest initial cost and running cost and is the most practical.

In the natural evaporation method, in order to maximize the area for water evaporation, efforts are made to use a bucket-shaped container with a large opening or to soak the bottom end of a woven hydrophilic fiber in water to increase the surface area of water using capillary force. are doing. If water were to be sliced into slices several millimeters thick and arranged in multiple layers vertically, the area for water evaporation could be greatly increased. As a result of repeated research on how to hold sliced water vertically several millimeters thick, we created a hollow structure with an internal thickness of several millimeters using a porous sheet made of hydrophobic polymer. However, it was previously discovered that by storing the sliced water in this hollow part, water can be held in any space, and moreover, the water can freely evaporate. (Specification of Japanese Patent Application No. 59-026741) As mentioned above, we have discovered a humidifier that uses natural evaporation but has a large humidifying capacity (Japanese Patent Application No. 59-026741).
-026741 specification), for example, in order to downsize,
Furthermore, a high-performance product with significantly improved humidification capacity was required.

Therefore, a natural evaporation type humidifier (hereinafter abbreviated as a moisture permeable membrane humidifier) uses a porous sheet of hydrophobic polymer (hereinafter abbreviated as a moisture permeable membrane) that prevents the passage of water and allows water vapor to pass through. ) In order to improve the performance of the moisture permeable membrane, we measured the material resistance (hereinafter abbreviated as moisture permeation resistance) that the moisture permeable membrane exhibits against the permeation of water vapor, and also investigated the complex-shaped pore structure of the moisture permeable membrane. was modeled as a set of bent capillaries, and the relationship between the humidifying capacity of a permeable membrane type humidifier and the permeation resistance and pore structure of the permeable membrane was clarified. We found the wet film first. (Tokugansho
60-026824 specification) [Problems to be solved by the invention] The moisture permeable membrane that can improve the performance of the moisture permeable membrane type humidifier described above has a low moisture permeation resistance, and its pore structure is composed of pores. The problem was that the mechanical strength was poor because the pores were densely distributed throughout the membrane. Another problem was that when the film thickness was increased to improve mechanical strength, the moisture permeation resistance increased in proportion to the film thickness.

This invention was made to solve the above problems, and it has a low moisture permeation resistance and a porous structure to achieve the low moisture permeation resistance, and also has excellent mechanical strength. The purpose of the present invention is to discover a moisture-permeable membrane and provide a high-performance moisture-permeable membrane type humidifier with greatly improved humidification capacity.

[Means for solving problems]

The humidifier of the present invention supplies water to a hollow part of a hollow structure through which water vapor can pass, and humidifies the air blown into the hollow structure by impregnating the water vapor that has passed through the hollow structure. As the material for the hollow structure, we used a composite porous sheet in which a porous sheet of hydrophobic polymer that prevents water from passing through and allows water vapor to pass through, and a breathable cloth that allows water and vapor to pass through. It is something.

[Effect]

In this invention, the breathable fabric that allows water and water vapor to pass through is responsible for the mechanical strength of the composite porous sheet, so the porous sheet of hydrophobic polymer has water repellency that prevents water from passing through, and moisture permeability that allows water vapor to pass through. 2
Therefore, even if the porous sheet has a high porosity and pores are distributed in a high density, the film thickness can be made thinner, so the moisture permeation resistance of the composite porous sheet can be reduced. . As a result, a high-performance humidifier with improved humidification capacity can be obtained.

〔Example〕

Hereinafter, this invention will be explained based on the drawings. 1st
The figure is a partially cutaway perspective view of an embodiment of the hollow structure according to the present invention. In the figure, 1 is a composite porous sheet (transparent (wet film), 2 is a spacer, 3 is a water supply port, 4 is a water discharge port, 5 is a porous structure, arrow A indicates the water supply direction, and arrow B indicates the water discharge direction.

Examples of the hydrophobic polymer porous sheet material used in this invention include polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polycarbonate, polyester, and fluorine resin, which prevent water from passing through,
It allows water vapor to pass through.

The breathable fabric according to the present invention may be any fabric as long as it allows water and steam to pass through freely, and woven or nonwoven fabrics such as vegetable fibers, chemical fibers, and metal fibers are used. The thickness is desirably 200 μm or more from the viewpoint of providing mechanical strength for reinforcing the porous sheet, and 500 μm or less is practically appropriate. From the viewpoint of processability, for example, a chemically woven fabric such as polyester is easily used.

The composite porous sheet is made by overlapping the above-mentioned porous sheet and cloth by partially point-joining them. If the entire surface is bonded, the holes will be closed, so to prevent moisture permeation resistance from decreasing, point bonding is done in spots at intervals of, for example, 5 mm or 10 mm.

In this embodiment, a coarse cloth (woven fabric or non-woven fabric) with a thickness of several mm is used as a spacer 2, both sides of this cloth are covered with a composite porous sheet 1, and a water supply port 3 and a water discharge port 4 are used. The hollow structure 5 was constructed by gluing or heat-sealing the ends except for the ends.
Note that the inside of the hollow structure 5 is the composite porous sheet 1.
When configured to be a breathable fabric, this fabric acts as a spacer and facilitates water supply.
Substitute for spacer.

It is appropriate for the composite porous sheet according to the present invention to have a moisture permeation resistance of 4 h.cmHg/Kg or less, as this greatly increases the amount of humidification as will be described later.
A range of cmHg/Kg or less is more desirable.

The moisture-permeable cup method specified in JIS-Z0208 is a method for evaluating the water vapor permeability of a non-porous polymer membrane. The moisture permeability resistance of the air layer in contact with both surfaces of the porous sheet is greater than the moisture permeation resistance of the sheet, and the above-mentioned moisture permeation cup method cannot accurately measure the moisture permeation resistance. Therefore, the inventors previously proposed a method for measuring the moisture permeation resistance of a porous sheet. [Reference: Takahashi,
etc.; Chemical Engineering Papers Vol.3No.5P.510-513 (1977)]
We also proposed a method for quantifying the pore structure by modeling the complex-shaped pore structure of a porous sheet as a collection of bent capillaries as shown in Figure 2. [Reference: Takahashi, et al.; Chemical Engineering Papers Vol. 5 No.
4P.391-396 (1979)] By the above method, the average pore size (c) and average curvature (≡c/l) of various moisture permeable membranes were determined.
In addition to measuring the number of pores per unit area (nc), using these moisture permeable membranes, the membrane area as described below was calculated.
We prototyped a 1.0m ² humidifier and measured the amount of humidification.
We examined these correlations in detail. As a result, it was revealed that there is a clear correlation between the amount of humidification and the moisture permeation resistance as shown in the characteristic diagram of FIG. However, the amount of humidification by a humidifier depends on the wind speed, temperature, and humidity of the blown air. The measured values in Figure 3 are wind speed
2 m/s, temperature of approximately 40°C, and relative humidity of approximately 20%. This value assumes warm air coming out of the heater when used as a humidifier, and the vertical axis represents the amount of humidification ( cc/h), and the horizontal axis is the moisture permeability resistance (h・cm
Hg/Kg). Note that the characteristic curve showing the relationship between the amount of humidification and moisture permeation resistance shifts upward because the amount of humidification increases when the wind speed or temperature increases, and shifts downward because the amount of humidification decreases when the relative humidity increases. As can be seen from the figure, the moisture permeation resistance
It is preferable that the amount of humidification is 4 h·cmHg/Kg or less because the amount of humidification increases significantly. The hollow structure of a moisture-permeable membrane humidifier is proportional to the membrane area. Therefore, this value is suitable, for example, for a humidifier with a membrane area of about 1.0 ^m2 in order to make it thin and compact, and is preferably 500 c.c./h or more as a humidification amount for a standard room of 6 to 8 tatami mats. can be secured.

Here, the moisture permeability resistance per unit area (R _H20 ) is defined as the value obtained by dividing the thickness (l) of the moisture permeable membrane by the moisture permeability coefficient (P _H20 ) as shown in the following equation.

P _H20 ≡l/P _H20 (1) The moisture permeability coefficient (P _H20 ) is determined by the pore structure of the porous membrane, so for porous membranes with the same pore structure, the moisture permeation resistance (P _H20 ) is proportional to the membrane thickness. .

For example, in order to commercialize a moisture-permeable membrane type humidifier, reliability of the moisture-permeable membrane is important, and in order to obtain the minimum necessary mechanical strength, a membrane thickness of 200 μm or more is required. Moisture permeability resistance of 4h・cm when film thickness is 200μm or more
To reduce the moisture permeability to Hg/Kg or less, set the moisture permeability coefficient to 5×10 ^-5
Must be at least Kg/mhcmHg.

The moisture permeability coefficient of porous sheets of hydrophobic polymers is generally in the range of 10 ^-6 to 10 ^-6 Kg/mhcmHg, and there are some sheets that satisfy the above value, but such porous sheets have a high porosity. The mechanical strength is poor because the pores are densely distributed throughout the membrane.

On the other hand, the moisture permeability resistance per unit area of a composite porous sheet in which a porous sheet with a membrane thickness of I ₁ and a moisture permeability coefficient of P _H20 (1) and a porous sheet with a membrane thickness of I ₂ and a moisture permeability coefficient of P _H20 are superimposed. P _H20 is given by the following formula.

P _H20 = I ₁ /P _H20 (1) + I ₂ /P _H20 (2) (2) For example, the former is a porous sheet that can prevent water from passing through but allow water vapor to pass (combined with water repellency and moisture permeability). , considering the latter as a breathable cloth that allows water and steam to pass through, P _H20 (1) is 10 ^-6 ~ 10 ^-4 Kg/mhcmHg
P _H20 (2) is in the range of 10 ^-4 to 10 ^-3 Kg/mhcmHg
within the range of Therefore, it is possible to reduce the overall moisture permeation resistance P _H20 by imparting mechanical strength to a fabric with a large P _H20 and by reducing I ₁ of a porous sheet with a small P _H20 . As a result, as shown in FIG. 3, the reliability of the moisture permeable membrane can be improved while greatly increasing the number of humidifiers. The thinner the I ₁ of the porous sheet, the more preferable it is, and in order to achieve this effect, it is preferably 100 μm or less.
Therefore, the thickness of the porous sheet is practically 10 μm or more, and desirably 100 μm or less in order to improve humidification performance and reduce moisture permeation resistance.

FIG. 4 is a configuration diagram showing a plate type humidifier which is an embodiment of the present invention, and in the figure, 6 is a hollow structure 5.
The water tank is located higher up and supplies evaporated water. Arrow C indicates the direction in which air is introduced, and arrow D indicates the direction in which air is discharged. In this embodiment, the moisture permeability resistance of the moisture permeable membrane is set to 4 h·cmHg/Kg or less, and the amount of humidification is greatly increased. It is folded and laminated in multiple layers to form a rectangular parallelepiped shape, which greatly increases the water evaporation area despite its small volume.
Humidification ability has improved dramatically. Although not shown in the figure, in order to maintain the shape of the hollow structure 5, a corrugated spacer, for example made of plastic, is inserted into the space of the stacked hollow structures to reinforce it.

Note that when the outside of the hollow structure 5 is configured to be the breathable cloth of the composite porous sheet 1, this cloth protects and reinforces the surface of the hollow structure 5, and thus serves as a spacing material.

During humidification operation, the water discharge port 4 is closed, and water is supplied from the water tank 6 to the hollow part of the hollow structure 5 through the water supply port 3 and held therein. By blowing dry air into the space of the hollow structure 5 from the direction C, water vapor passes through the composite porous sheet (moisture permeable membrane) and is contained in the air, and the humidified air exits in the two directions. go. Evaporated water is replenished from the tank 6 as needed. The water outlet 4 is used to drain water by opening it when not in use for a long period of time, or to remove limescale by circulating water.

FIG. 5 is a block diagram showing a spiral type humidifier according to another embodiment of the present invention. In the figure, 7 represents a wavy spacer, for example, one made of plastic, and the hollow structure 5 is formed of a wavy spacer. It is wound into a honeycomb-like columnar shape through the spacing material 7, and in addition to increasing the humidifying capacity of the composite porous sheet as shown in Fig. 4, the evaporation area of water is greatly increased despite its small volume. The humidifying ability has improved dramatically. Humidified air is obtained by blowing dry air while supplying water from the water tank 6.
The hollow structure 5 and the spacer 7 may be bonded together, but they do not need to be bonded together. Although not shown in the figure, a water outlet can be provided by passing a pipe through the center.

Example 1 Film thickness is 100μm, moisture permeability coefficient is 5×10 ^-5 Kg/mhcm
Hg polyethylene porous sheet and film thickness
Polyethylene nonwoven fabrics of 200 μm and a moisture permeability coefficient of 4×10 ^-4 Kg/mhcmHg were overlapped and point-fused at 1 cm intervals. The moisture permeability resistance of the resulting composite porous sheet was measured to be 2.8h.cmHg/Kg. This composite porous sheet is used as a moisture permeable membrane with a width of 22 mm.
It was cut into strips with a length of 5.1 m.

Next, cut a piece of nonwoven fabric with a thickness of 4 mm, width of 10 cm, and length of 5.0 m, cover it with the above porous membrane as a spacer, and heat seal the side where the two porous membranes overlap using a heat sealer. did. Next, 6mm in diameter on both ends,
A polyethylene tube with a length of 5 cm was inserted and the porous membrane was heat-sealed to produce a hollow structure as shown in FIG. 1. In order to prevent water leakage from the interface between the polyethylene tube and the porous sheet, adhesive was used to seal as necessary.

Next, a wavy spacer made of polyethylene was used to create a fourth
A plate-type humidifier as shown in the figure was created. In order to reduce pressure loss during ventilation, the wave height of the wavy spacing material was set to 6 mm, and the pitch was set to 9 mm. The membrane area of the humidifier was approximately 1.0 m ² .

Next, attach the above humidifier to the front of the heat exchanger of the fan coil unit, which has 50℃ hot water flowing through it.
The temperature of ℃ was blown. The amount of humidification depends on the wind speed.
The humidification amount at 1 m/s is 560 c.c./h, and the
When the speed was increased to 2 m/s, the humidification amount increased to 650 c.c./h.

Example 2 Film thickness is 50μm, moisture permeability coefficient is 5×10 ^-5 Kg/mhcm
Hg polyethylene porous sheet and film thickness
Polyethylene nonwoven fabrics of 200 μm and a moisture permeability coefficient of 4×10 ^-4 Kg/mhcmHg were overlapped and point-fused at 1 cm intervals. The moisture permeation resistance of the resulting composite porous sheet was measured to be 1.8h.cmHg/Kg. This composite porous sheet is used as a moisture permeable membrane with a width of 22 mm.
It was cut into strips with a length of 5.1 m.

A hollow structure was produced in the same manner as in Example 1.

Next, a wavy spacer made of polyethylene was used to create a fourth
A plate-type humidifier as shown in the figure was created. The membrane area of the humidifier was approximately 1.0 m ² .

Next, attach the above humidifier to the front of the heat exchanger of the fan coil unit, which has 50℃ hot water flowing through it.
The temperature of ℃ was blown. The amount of humidification is 710 at a wind speed of 1m/s
cc/h, 2m/s was 820c.c./h.

Example 3 A hollow structure was prepared in the same manner as in Example 1 by using the same composite porous sheet moisture permeable membrane as in Example 2 and cutting it into a strip having a width of 12 cm and a length of 10.1 m.

Next, a spiral type humidifier as shown in Fig. 5 was made using polyethylene wavy spacing material with a wave height of 6 mm and a pitch of 9 mm.

The membrane area of the humidifier is approximately 1.0m ² .

Next, attach the above humidifier to the front of the heat exchanger of the fan coil unit, which has hot water of 50℃ flowing, and
The temperature of the air was blown. Humidification amount is 720 at wind speed 1m/s
cc/h, 2m/s was 830c.c./h. When the membrane area was the same, the humidification amount of the plate type humidifier and the spiral type humidifier was almost the same.

Example 4 Film thickness is 50μm, moisture permeability coefficient is 8×10 ^-5 Kg/mhcm
Hg polyvinyl chloride porous sheet and film thickness
Polyethylene woven fabrics of 150 μm and a moisture permeability coefficient of 5×10 ⁻⁴ Kg/mhcmHg were overlapped and bonded at 1 cm intervals using an adhesive. The moisture permeation resistance of the resulting composite porous sheet was measured to be 1.0h.cmHg/Kg. This composite porous sheet was used as a moisture permeable membrane and cut into strips with a width of 12 cm and a length of 10.1 m to produce a hollow structure in the same manner as in Example 1.

Next, a spiral humidifier was produced in the same manner as in Example 3.

The membrane area of the humidifier was approximately 1.0 m ² .

Next, attach the above humidifier to the front of the heat exchanger of the fan coil unit, which has 50℃ hot water flowing through it.
The temperature of ℃ was blown. The amount of humidification is 1000 at a wind speed of 1ms.
cc/h, 2m/s was 1200c.c./h. When the pore characteristics and moisture permeability characteristics of porous membranes were the same, the humidification amount was almost the same even if the membrane materials were different.

The moisture permeable membrane used in the above examples was lined with a woven or nonwoven fabric, so it had excellent mechanical strength and improved workability.

In addition, the humidifier according to the present invention has the structure shown in Fig. 4 or 5 and is housed in a casing and is used by being attached to the dry air outlet of an air conditioner or heater, but when used independently as a humidifier. It can also be used in combination with a blower such as a fan or blower.

〔Effect of the invention〕

As described above, according to the present invention, water is supplied to the hollow part of a hollow structure through which water vapor can pass, and the air blown to the hollow structure is humidified by being impregnated with the water vapor that has passed through the hollow structure. In things,
As a material for the hollow structure, a composite porous sheet is used, which is a composite porous sheet made by laminating a hydrophobic polymer porous sheet that prevents water from passing through and allows water vapor to pass through, and a breathable cloth that allows water and water vapor to pass through. As a result, the composite porous sheet can be made to have excellent mechanical strength and low moisture permeation resistance, resulting in the effect of obtaining a high-performance humidifier with greatly improved humidification capacity.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway perspective view of an embodiment of a hollow structure according to the present invention, FIG. 2 is an explanatory diagram showing a model of the shape of pores in a porous sheet according to the present invention, and FIG. A characteristic diagram showing the correlation between the moisture permeation resistance and the amount of humidification of the porous sheet according to the present invention, FIG. 4 shows the structure of a humidity sensor according to one embodiment of the present invention, and FIG. 5 shows the structure of a humidity sensor according to another embodiment. It is a diagram. In the figure, 1 is a composite porous sheet (moisture permeable membrane) made by laminating a porous sheet of hydrophobic polymer and a breathable cloth, 2 is a spacer, 3 is a water supply port, 4 is a water discharge port, and 5 6 is a hollow structure, 6 is a water tank, 7 is a wave spacing member, A is a water supply direction, B is a water discharge direction, C is an air introduction direction, and D is an air discharge direction. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Scope of Claims] 1. A humidifier that supplies water to a hollow part of a hollow structure through which water vapor can pass, and humidifies the air blown into the hollow structure by impregnating the water vapor that passed through the hollow structure, As the material for the hollow structure mentioned above,
A humidifier characterized by using a composite porous sheet made by laminating a hydrophobic polymer porous sheet that prevents water from passing through and allows water vapor to pass through, and a breathable cloth that allows water and water vapor to pass through. 2. The humidifier according to claim 1, wherein the composite porous sheet is a porous sheet and a breathable cloth partially bonded and overlapped at points. 3. The humidifier according to claim 1 or 2, wherein the porous sheet has a thickness of 10 to 100 μm. 4. The humidifier according to any one of claims 1 to 3, wherein the inside of the hollow structure is made of a porous sheet and the outside is made of breathable cloth. 5. The humidifier according to any one of claims 1 to 3, wherein the inside of the hollow structure is made of breathable cloth and the outside is made of a porous sheet. 6. Claim No. 6, characterized in that the hydrophobic polymer of the material of the porous sheet is any one of polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polycarbonate, polyester, and fluororesin. The humidifier according to any one of items 1 to 5.