JP2000005067A - Electric water heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve heat insulating property by sealing a space between heat- resistant laminate films arranged with core material to be vacuum and providing an aluminum vapor-deposited layer at the heat-resistant laminate films to form a vacuum heat insulating material provided in the periphery of a water reserving container. SOLUTION: Concerning a water reserving container for reserving hot water inside, the vacuum heat insulating material is wound on its side surface to suppress the escape of the heat of the container from the side surface of the main body of the electric water heater. Concerning this vacuum heat insulating material, the core material 22 and a gas capturing agent 35 are housed in an inner bag 23 and the bag 23 is housed in the bag of heat-resistant laminate 24 under vacuum. The laminate 24 consists of a seal layer 25, a gas barrier layer 26 and a protecting layer 29, which is formed with a polyester layer 27 and a nylon layer 28. Then, the layer 26 is formed by vapor-depositing aluminum or a compound to absorb slightly entering gas with the agent 35 to keep the degree of vacuum.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric water heater for supplying hot water for drinking at home or office.

[0002]

2. Description of the Related Art Electric water heaters can be heated for a variety of purposes, such as tea and coffee, as well as hot water for milk for infants, because water can be heated and kept at a constant temperature when water is connected to the power supply. It is used.

In addition, various heat insulating materials have been used because it is necessary to keep hot water warm for a long time. Examples thereof include an organic heat insulating material such as urethane, an inorganic heat insulating material such as glass wool and ceramic wool, a material using a metal reflection plate, and a material in which a vacuum is applied between a glass and metal double container.

[0004]

However, since the temperature of an electric water heater rises to about 100 ° C. for an organic heat insulating material such as urethane, the heat insulating material is deteriorated and the heat insulating property is extremely deteriorated. there were. In addition, there is a problem that it is very difficult to reuse because of performing injection molding firing, and that the environmental load is large. Further, although the inorganic heat insulating material has excellent durability performance, there are problems that the heat insulating performance is low, and fine fibers and the like are generated from the surface, and the hand is stiff and difficult to handle. If the heat insulating property is low, the amount of heat retention power of the electric water heater becomes large, and there is a problem that much energy is used. The double container made of glass or metal has a problem that it must be strong enough to withstand a vacuum, so that it becomes very heavy, and the shape can only be a circle or a sphere.

[0005]

SUMMARY OF THE INVENTION The present invention is to solve such a problem, and uses a vacuum heat insulating material in which a core material is arranged and a space between heat-resistant laminated films is sealed in a vacuum. This makes it possible to realize an electric water heater that can be easily handled in various shapes and maintain high heat insulation without deterioration.

According to the invention, the space between the heat-resistant laminate films on which the core material is disposed is sealed in a vacuum. Since the inside of the heat insulating material is kept in a vacuum, the heat insulating performance is very excellent. Since the heat-resistant laminate film has heat resistance, it does not deteriorate over time. Note that at least aluminum vapor deposition or compound vapor deposition is used for the gas barrier layer of the heat-resistant laminate film. These have lower heat conduction and are more excellent in heat insulation than the case where a metal sheet is used as a gas barrier material. Further, since the core material is covered with the heat-resistant laminate film, the core material does not come into direct contact with the hand, and the work is very easy. Further, since the shape of a flat plate or the like is possible, it can be used in various portions of the electric water heater. Since an electric water heater keeps hot water at a high temperature, a heat insulating material having high heat insulating performance is very effective. In addition, since it can be easily disassembled and separated, reuse and environmental load can be extremely reduced.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS To solve the above-mentioned problems, the present invention provides a water storage container, a heater for heating water in the water storage container, a hot water supply path for discharging water to the outside, A vacuum heat insulating material is provided around the container, and the vacuum heat insulating material is
The space between the heat-resistant laminate films on which the core material is arranged is sealed in a vacuum, and the heat-resistant laminate film is an electric water heater having an aluminum vapor-deposited layer.

[0008] The vacuum heat insulating material has high heat insulating performance, is light in weight, and has good handleability. Therefore, the heat insulating power is smaller than that of an organic heat insulating material such as urethane or an inorganic heat insulating material such as glass wool. An electric kettle that is lighter than the one can be realized. Furthermore, since the laminated layer uses an aluminum vapor-deposited layer, the heat conduction on the surface is small and the heat insulation performance is high, so that an electric water heater having a smaller heat retaining power can be realized.

[0009] Further, in the heat-resistant laminate film, a vacuum heat-insulating material composed of a heat-resistant laminate film having an aluminum vapor-deposited layer and a heat-resistant laminate film having an aluminum foil layer provides a long-term heat insulation performance. In order to maintain the electric power, an electric water heater that can maintain a small heat retention power for a long time can be realized.

In addition, a water storage container, a heater for heating water in the water storage container, and a hot water supply path for discharging water to the outside are provided, and a vacuum is applied between the heat-resistant laminated film in which the core material is disposed. By using a compound vapor deposition layer for sealing and laminating, heat conduction through the surface is further reduced,
Further, since the heat insulation performance is high, an electric water heater that requires less heat retention power can be realized.

Further, by using a vacuum heat insulating material having a silica vapor-deposited layer as a compound vapor-deposited layer in a heat-resistant laminate film, an electric water heater having a small heat-retaining power can be realized.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

Embodiment 1 Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. In FIG. 1, reference numeral 1 denotes a main body (hereinafter simply referred to as a main body) of an electric water heater, and a water storage container 2 having an inner diameter of 184 mm and a depth of 250 mm for storing hot water therein.
(Hereinafter simply referred to as container 2). 3 is container 2
It is an inner plug attached so as to seal the mouth. Reference numeral 4 denotes an upper cover that covers the upper portion of the main body 1 so as to be opened and closed. Reference numeral 5 denotes a vapor passage provided in the upper lid, one end of which passes through the inner plug 3 and communicates with the inside of the container 2, and the other end communicates with the atmosphere.
Reference numeral 6 denotes a water leakage prevention valve, which is arranged in the steam passage 5, and shuts off the steam passage 5 when the vehicle falls down.

Here, the steam passage 5 is complicatedly bent. As a result, when the pressure inside the container 2 becomes higher than that in the atmosphere, such as when the water in the container 2 boils, steam is discharged out of the main body through the steam passage 5. The air (hereinafter referred to as inside air) between the upper lid 4 and the upper lid 4 is not mixed.

Reference numeral 7 denotes a motor provided at the bottom between the main body 1 and the container 2, and reference numeral 8 denotes a pump driven by the motor 7, and its suction port 9 communicates with the bottom of the container 2. Reference numeral 10 denotes a discharge port of the pump 8, which communicates with 11 tapping pipes constituting a part of the tapping path. Reference numeral 12 denotes a tap hole from which the tap water flows out of the electric water heater. Reference numeral 13 denotes a heater for heating, which is attached to the lower part of the container 2 with a central portion missing like a donut. Reference numeral 14 denotes a temperature detector, which is attached to the lower part of the container 2 and the center of the heater 13. Reference numeral 15 denotes a start switch for driving the motor 7, which has a variable resistor.
Works through. Reference numeral 18 denotes a compression spring, which always urges the rod 17 upward. Reference numeral 19 denotes a control device which receives a signal from the temperature detector 14 and controls the heater 13 and the like. 20 is a vacuum heat insulating material wound on the side of the container 2,
It plays a role in suppressing the heat of the container 2 from escaping from the side surface of the main body 1.

The vacuum heat insulating material 20 and the vacuum heat insulating material 21 used here will be described with reference to the drawings. FIG. 2 shows a sectional view of the vacuum heat insulating material 20. 22 is a core material of the vacuum heat insulating material, and 35 is a gas trapping agent. The core material 22 and the gas capturing agent 35 are
3 is stored. The inner bag 23 containing the core material 22 is further housed in a heat-resistant laminate 24 bag in a vacuum state. The laminate 24 includes a seal layer 25, a gas barrier layer 26, and a protective layer 29. The protective layer 29 includes a 27 polyester layer and a 29 nylon layer. The core material 22 has a low thermal conductivity, and the holes and gaps need to communicate with the outside. As the gas trap 35, 20 g of zirconium, iron, vanadium and a mixture of these compounds were used. As the core material 22, an organic or inorganic material can be used, but when used at a high temperature such as an electric water heater, a material that does not generate gas is required. Examples of materials that do not generate gas include pearlite and shirasu balloon, and in this embodiment, synthetic silica was used as the core material 22. Since the particles of synthetic silica are very fine, the thermal conductivity of the particles is very low. Furthermore, if the pressure is 10 torr or less, the material exhibits a very small thermal conductivity regardless of the pressure. Therefore, it is a very suitable material under the condition that the molecular motion of air is high at a high temperature. Furthermore, since it is a component that is naturally present in a large amount, the burden on the environment is very small and the treatment after use is very simple.

The above-listed core materials are very difficult to handle, for example, when powder or short fiber is used to handle the powder, the powder soars up or gives a tingling stimulus to the hands. However, since the vacuum heat insulating material described in the present embodiment is covered with the laminate bag, the powder does not fly up and does not irritate the hand, and is extremely excellent in handling. The sealing layer 25 has a role of bonding the heat-resistant laminate 24 and maintaining a vacuum inside. It is necessary that the seal layer can be easily heat-sealed, but since the temperature of the electric water heater is about 100 ° C., it is necessary that the temperature does not deteriorate at 100 ° C. Therefore, in this embodiment, unstretched polypropylene is used as the seal layer 25, and heat sealing is performed at the position 30.
Since this polypropylene needs heat resistance, the degree of crystallinity is increased with a homopolymer. Gas barrier layer 2
As No. 6, aluminum deposition was used.

The gas barrier layer has a function of blocking gas that passes through the resin of the heat-resistant laminate film. The thicker the gas permeation barrier, the higher the reliability. However, when used as a gas barrier layer of a vacuum heat insulating material, the thinner the heat conduction, the lower the heat conductivity, and thus the better the heat insulating performance. Therefore, in this embodiment, the vapor deposition of aluminum is used as the gas barrier layer 26, and the gas entering slightly is adsorbed by the gas capturing agent 35 to maintain the degree of vacuum. The protective layer 29 has a role of protecting the seal layer 25 and the gas barrier layer 26. The polyester layer 27 was disposed at a position of the protective layer 29 directly in contact with the gas barrier layer.

In this embodiment, polyethylene terephthalate (hereinafter referred to as PET) is used for the polyester layer 27. Since PET has excellent heat resistance, it is very suitable as a protective layer of an electric water heater. Further, the protective layer 29
The nylon layer 28 is arranged as the outermost layer. Nylon is hygroscopic and is not normally placed on the outermost layer. This is because the laminated film is deformed by the moisture absorption of nylon. However, an electric water heater usually has little contact with water or steam. The electric water heater has a high possibility of being in contact with other parts and the like at the time of attachment and detachment, and is likely to be damaged. However, nylon has high sliding performance,
Less scratches. In addition, by arranging slippery nylon on the outermost layer, mounting can be performed smoothly and assembly performance is improved. Nylon also has high tensile strength. Therefore, even when pierced by protrusions, it has the ability to stretch and make it difficult to make holes, so it is not possible to arrange nylon as the outermost layer as a heat-resistant laminate film of vacuum insulation material used for electric water heaters Very important.

FIG. 3 shows the flat shape of the vacuum heat insulating material 20. Numeral 32 is a portion containing the core material 22 and having a heat insulating property as a vacuum heat insulating material. Reference numeral 32 denotes a heat seal portion, which has a portion 30 to which the seal layer 25 is welded, and is a portion not containing a core material. Vacuum insulation 2
1 has a rectangular shape. When wound around the container 2, the heat-sealed portion is folded. At this time, it is wound around the container 2 so that the heat-sealed portion comes outside the cylindrical shape as shown in FIG. In this way, the heat-sealed portion 32 of the heat-resistant laminate does not come into direct contact with the container 2 containing hot water, so that deterioration in durability can be further reduced.

Hereinafter, the operation of this embodiment will be described. Container 2
When water is supplied after water is supplied to the container, the water temperature in the container 2 is measured by the temperature detector 14, a signal thereof is sent to the controller 19, and the controller starts to energize the heater 13.
When the water in the container 2 boils, the energization of the heater 13 ends. Then, upon receiving a signal from the temperature detector 14,
The control device 19 controls the heater 13 so that the temperature of the container 2 becomes constant. Push the push button 16 when tapping. The motor 7 is operated, and the water in the container 2 is discharged by the pump 8 from the tap hole 12 to the outside of the electric water heater through the tap hole 11 and used. An experimental example will be described below.

<Experimental Example 1> The above-described electric water heater (referred to as a vapor-deposited heat insulating material in this experimental example) and the above-described electric water heater with the vacuum heat insulating material 20 removed (referred to as no heat insulating material in this experimental example), What uses urethane foam (referred to as urethane heat insulator in this experimental example) instead of the vacuum heat insulating material 20, uses glass wool (referred to as glass wool heat insulator in this experimental example), and vacuums the above electric water heater A laminate using aluminum as the laminate of the heat insulating material 20 (referred to as an aluminum heat insulating material in this experimental example) was prepared.

Water was placed in these electric kettles, and the heat retention power was measured at the initial stage and after the endurance (after 3500 use). Note that the temperature of the heat retaining water is 97 ° C. and the ambient temperature is 20 ° C. The measurement was performed after a sufficient equilibrium state was reached. The thermal conductivity and the heat retention power of the heat insulating material at this time are shown in (Table 1).

[0024]

[Table 1]

As described above, in the case where the vacuum heat insulating material using the aluminum laminated film is used, the heat retention power can be kept low. By using a vacuum heat insulating material using an aluminum vapor-deposited laminated film as described above, an electric water heater with low heat retention power can be realized.

(Embodiment 2) FIG. 1 shows an arrangement in which a vacuum heat insulating material is arranged on the upper lid of an electric water heater. 1 to 20 are the same as in the first embodiment. FIG. 5 is a sectional view of the vacuum heat insulating material 20. 22 to 35 are the same as in the first embodiment. 26 is 6 μm
Of aluminum foil. FIG. 3 shows the vacuum insulation material 20.
Represents the shape of a flat plate. The gas barrier layer on one side is vapor-deposited aluminum, and the gas barrier layer on the other side is aluminum foil. As shown in FIG. 4, the container is wound around the container 2 such that the heat-sealed portion comes outside the cylindrical shape. here,
The aluminum foil is inside the cylinder and the deposited aluminum is outside. Since the inside of the cylinder is in direct contact with the container 2, the temperature becomes high and durability is required. Therefore, a highly reliable aluminum foil is placed inside. The heat transmitted on the surface of the heat insulating material is slightly increased by using aluminum foil on one side as compared with the surface aluminum vapor deposition product. However, since the gas intrusion is reduced, the amount of the gas trapping agent 35 is small and the same reliability can be obtained. In this embodiment, the amount of the gas capturing agent 35 is 1 g.

<Experimental Example 2> In the above-described electric water heater (referred to as a single-sided aluminum foil product in this experimental example) and the electric water heater, the laminated film 2 of the vacuum heat insulating material 21 was used.
The gas barrier layers 26 and 36 of No. 4 were prepared by vapor deposition of aluminum (deposited in this experimental example).

Water was placed in these electric kettles, and the heat retention power was measured at the initial stage and after the endurance (after 3500 use). Note that the temperature of the heat retaining water is 97 ° C. and the ambient temperature is 20 ° C. The measurement was performed after a sufficient equilibrium state was reached. Results (Table 2)
Shown in

[0029]

[Table 2]

As described above, in the case where the aluminum foil is used only on the side directly in contact with the container 2 which is a high-temperature portion, the heat insulating performance can be maintained for a long time with a small amount of gas scavenger. Therefore, by using aluminum vapor deposition and a laminated film of aluminum foil, an electric water heater that maintains low power consumption for a long time can be realized.

(Embodiment 3) FIG. 1 shows an arrangement in which a vacuum heat insulating material is arranged on the upper lid of an electric water heater. 1 to 20 are the same as in the first embodiment. FIG. 2 is a sectional view of the vacuum heat insulating material 20. 22 to 25 and 27 to 35 are the same as in the first embodiment.
Reference numeral 26 denotes an aluminum foil having a thickness of 6 μm. FIG. 3 shows the flat shape of the vacuum heat insulating material 20. As shown in FIG. 4, the container is wound around the container 2 such that the heat-sealed portion comes outside the cylindrical shape. Here, when a metal is used for the gas barrier layer, the gas barrier property is improved, but the heat transmitted through the surface of the heat insulating material is increased when the metal is used. Therefore, in the present embodiment, vapor deposition of a compound was used. As the compound, diboron trioxide or magnesium difluoride can be used, but silica was used in this example. Silica can easily form a vapor-deposited layer, so that it can have reliable gas barrier performance. In this embodiment, 25 g of the gas capturing agent 35 was used.

<Experimental Example 3> The above-described electric water heater (referred to as a silica-deposited product in the present experimental example) and the above-described electric water heater in which the gas barrier layer 26 of the laminated film 24 of the vacuum heat insulating material 21 was subjected to aluminum vapor deposition (this experimental example) Then, an aluminum vapor-deposited product) was prepared.

Water was placed in these electric kettles, and the heat retention power was measured at the initial stage and after the endurance (after 3500 use). Note that the temperature of the heat retaining water is 97 ° C. and the ambient temperature is 20 ° C. The measurement was performed after a sufficient equilibrium state was reached. The results (Table 3)
Shown in

[0034]

[Table 3]

As described above, a vacuum heat insulating material comprising a laminated film having a compound vapor deposition, particularly a silica vapor deposition, using a gas trapping agent was able to have a very high heat insulating performance. Therefore, by using a vacuum insulating material made of a laminated film having compound deposition, particularly silica deposition, an electric water heater that can maintain very low power consumption for a long period of time can be realized.

[0036]

As apparent from the present embodiment, claim 1
According to the described invention, a water storage container, a heater for heating water in the water storage container, and a hot water supply path for discharging water to the outside are provided, and a space between the heat-resistant laminated film in which the core material is disposed is provided. It is sealed in vacuum and uses a vacuum insulation material with an aluminum deposition layer for lamination.It is very easy to handle, it can be used in various shapes, and it has excellent heat insulation performance, so it keeps heat An electric water heater with very little power can be obtained.

According to a second aspect of the present invention, there is provided a heat-resistant laminated film comprising a heat-resistant laminated film having an aluminum vapor-deposited layer and a vacuum heat-insulating material comprising a heat-resistant laminated film having an aluminum foil layer. It is possible to obtain an electric water heater having excellent heat insulation properties and using a heat insulating material having a long life, and having very little long-term heat retention power.

According to the third aspect of the present invention, a heat storage container, a heater for heating water in the water storage container, and a hot water supply path for discharging water to the outside are provided, and a core material is provided. By sealing the space between the laminated films in a vacuum and using a vacuum heat insulating material having a vapor deposition layer of the compound for the lamination, a heat insulating material having a higher heat insulating property can be used. You can get fewer electric kettles.

According to the fourth aspect of the present invention, since the compound vapor deposition layer is a silica vapor deposition layer, a more stable and highly heat-insulating heat insulating material can be used. You can get fewer electric kettles.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an electric water heater according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the vacuum heat insulating material of the electric water heater in the embodiment of the present invention.

FIG. 3 is a perspective view of a vacuum heat insulating material of the electric water heater in the embodiment of the present invention.

FIG. 4 is a diagram showing a state in which the vacuum heat insulating material of the electric water heater according to the embodiment of the present invention is cylindrical.

FIG. 5 is a sectional view of a vacuum heat insulating material of an electric water heater according to another embodiment of the present invention.

[Explanation of symbols]

 2 Water Storage Container 13 Heater 20 Vacuum Insulation Material 22 Core Material 23 Inner Bag 24 Heat Resistant Laminate Film 26 Gas Barrier Layer 35 Gas Capture Material

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kiyoyoshi Takada 1006 Kazuma Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. F term (reference) 4B055 AA34 BA23 BA28 CA01 CA09 CA71 CC43 CC52 CD61 DA02 DB02 FA03 FA06 FB02 FB13 FB24 FB33 FC09 FC11 FE01

Claims (4)

[Claims] 1. A water storage container, a heater for heating water in the water storage container, a hot water supply path for discharging water to the outside, and a vacuum heat insulating material provided around the water storage container, An electric water heater having a vacuum-sealed space between the heat-resistant laminate films on which the core material is arranged, and having the aluminum layer deposited on the heat-resistant laminate film. 2. The electric water heater according to claim 1, wherein the heat-resistant laminate film comprises a heat-resistant laminate film having an aluminum vapor-deposited layer and a heat-resistant laminate film having an aluminum foil layer. 3. A water storage container, a heater for heating water in the water storage container, a hot water supply path for discharging water to the outside, and a vacuum heat insulating material provided around the water storage container, wherein the vacuum heat insulating material is provided. An electric water heater characterized in that the material is sealed in a vacuum between heat-resistant laminated films on which a core material is arranged, and a vacuum heat insulating material having a compound vapor-deposited layer is used for lamination. 4. The electric water heater according to claim 3, wherein the compound vapor-deposited layer is a silica vapor-deposited layer.