JPH11108466A - Solar heat hot water device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a solar heat collector from being broken even if the drainage of the solar heat collector is neglected to freeze it in the cold season, to simplify a structure and lower cost by providing a float with an upper surface opened which is vertically movable in an inner casing. SOLUTION: A float 5 is housed in an inner casing 3. The float 5 is formed in the shape of a box with an upper surface opened. On the float 5, two or more solar heat collecting fins 6 composed of protruding members are erected or provided upright in inclined positions. On the lower surface of the float, two or more radiating fins protruding downward are provided. The solar heat collecting fins 6 are provided in order to increase a heat collecting area for absorbing more solar energy. The radiating fins are provided in order to quickly transfer solar heat absorbed by the float 5 including the solar heat collecting fins 6 to water in a bottom. The float 5 is housed in the inner casing 3 by holding a small space between the side surfaces of the float 5 and the inner peripheral side surfaces of the inner casing 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solar water heater, and more particularly to a structure of a heat collector of a solar water heater.

[0002]

2. Description of the Related Art Conventionally, there are a solar water heater of a pumping type, a natural circulation type, a heat pipe type and the like, and a heat collector of these solar water heaters has the following configuration. That is, in the pumping type, water is supplied to several black plastic pipes made of polyethylene or the like, and the plastic pipes are irradiated with sunlight to heat the pumping water. It was set according to the number of units.
In the natural circulation type, a heat collector made of a stainless steel plate or the like coated with a black paint or a black chemical conversion treatment film is irradiated with sunlight to heat water in contact with the heat collector. In the heat pipe type, the heat collector is composed of a heat pipe, and the heat energy absorbed here is transferred to the hot water storage section through the heat pipe.

[0003]

2. Description of the Related Art In the above-mentioned solar water heaters, in both the pumping type and the natural circulation type, freezing of the heat collector during the cold season becomes a problem. That is, it is inevitable to drain the water and empty the heat collector before sunset. Failure to do so will cause damage to the heat collector. The heat pipe type eliminates the problem of freezing of the heat collector during the cold season and does not require drainage. However, in this heat pipe type, the heat pipe used for heat transfer is not inexpensive, so the price of the solar water heater itself is inevitably expensive, and the heat conversion efficiency of the heat pipe in the hot water storage tank is not sufficient. However, there is a problem that the area of the heat collector has to be enlarged in order to compensate for it.

[0004]

SUMMARY OF THE INVENTION The present invention aims at solving the problems of the conventional solar water heater, that is, even if the collector is not frozen during the cold season and the drain is frozen, damage to the collector is prevented. It is an object of the present invention to provide a solar water heater that does not bring about it, has a simple structure, and reduces the price without using expensive members.

[0005]

The means and the like will be described below with reference to FIGS. 1 and 2. The solar water heater 1 according to the present invention includes an inner surface of an outer enclosure 2 having an open top and an inner enclosure 3 having an open top.
A structure in which the outer casing 2 and the inner casing 3 are integrated by interposing a spacer 4 between the outer casing and the outer face including the bottom face, and a float 5 which is vertically movable inside the inner casing 3 and has an open top surface is arranged. At least two heat-collecting fins 6 each of which is a projecting member having the float 5 erected or erected on the upper surface thereof, and two or more heat-radiating fins 7 are disposed on the lower surface thereof by projecting downward. And a configuration in which a lid 8 is provided on the upper surface of the envelope 2.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a solar water heater 1 of the present invention, an envelope 2 is made of a glass plate or a synthetic resin having transparency such as acrylic or polycarbonate, and is a so-called box-shaped one having an open upper surface. Here, the condition that transparency is provided is to enable the transmission of sunlight.

The inner envelope 3 has a so-called box-like shape with an open top, like the outer envelope 2, and has a size such that the inner envelope 3 can be stored in the outer envelope 2 with a small space therebetween. Size. In the present invention, the envelope 3 uses a core material made of a plate material of aluminum or aluminum alloy having excellent ductility and a clad material made of an aluminum alloy plate. Here, at least 3% by weight of silicon is contained in the clad material, and the surface of the clad material is an infrared radiator having a black oxide film (alumite film) formed by anodizing treatment to have a natural color. This utilizes the fact that the infrared radiator has an extremely high endothermic effect. Here, in order to further enhance the heat absorbing effect of the inner container 3, it is desirable to provide grooves, irregularities or projections on the outer surface of the inner container 3 for increasing the specific surface area.

The inner casing 3 is accommodated in the outer casing 2 while maintaining a small interval between the inner casing 3 and the outer casing 2. That is, the spacer 4 is interposed between the outer surface including the bottom surface of the inner envelope 3 and the inner surface of the outer envelope 2 to maintain a narrow interval corresponding to the thickness of the spacer 4 and to allow the spacer 4 and the outer envelope 2 to be separated from each other. The inner surface and the outer surface including the spacer 4 and the bottom surface of the inner container 3 are fixed to each other using an adhesive, a double-sided tape, or the like, thereby integrating the outer container 2 and the inner container 3. Here, in the integration, the open upper surface of the outer envelope 2 and the open upper surface of the inner envelope 3 are flush with each other.

The reason why the spacer 4 is interposed between the outer casing 2 and the inner casing 3 to maintain a small interval is to suppress heat radiation from the inner casing 3 to the outside. In other words, the infrared radiator painted black absorbs solar energy well,
On the other hand, the heat radiation is also large, so that the water temperature cannot be raised higher as a solar water heater unless the heat radiation is suppressed. Therefore, in the present invention, as a measure for suppressing the heat radiation, the outer surface of the inner enclosure 3 is covered with air having extremely low thermal conductivity. Specifically, the outer circumference of the inner envelope 3 is covered with the outer envelope 2 with the spacer 4 interposed therebetween. This not only suppresses heat radiation from the enclosure 3 to the outside, but also
The effects of wind and direct contact with cooler outside air can be cut off. Here, the spacer 4
It is desirable to use a member having low thermal conductivity for the purpose of interposition, and synthetic resin, ceramic, and the like are preferable members.

A float 5 is accommodated in the inner enclosure 3. The float 5 has a box shape with an open top surface, and has two or more projecting members on the top surface thereof, each of which is a plate-like, net-like, rod-like, cylindrical, or honeycomb-like projecting member that is erected or erected. The heat collecting fin 6 has two or more heat radiating fins 7 projecting downward from the lower surface thereof. Here, the heat collecting fins 6 are provided to increase the heat collecting area to absorb more solar energy, and the heat radiating fins 7 absorb the solar heat absorbed by the float 5 including the heat collecting fins 6. It is installed to quickly transfer heat to the water at the bottom.

[0011] The float 5 comprises a side surface of the float 5 and the inner enclosure 3.
Are stored in the inner enclosure 3 with a small space between the inner peripheral surface and the inner peripheral side surface. The reason why the narrow interval is maintained here is to make it possible to float the float 5 upward by buoyancy when water is supplied from the outside into the inner enclosure 3 through the water supply / drain pipe 9. That is, the float 5 is connected to the inner container 3.
This is because the water can be moved up and down by the water level 10 in the inside. In response to this, as long as a predetermined amount of water is present in the inner container 3, the float 5 is always in contact with the water, thereby enabling heat transfer to the water.

The float 5 has at least the float 5 main body and the heat collecting fins 6 made of the same material as the inner casing 3. This is for enabling more heat absorption as in the case of the envelope 3.

On the upper surface of the envelope 2, a glass plate or a flat cover made of a synthetic resin such as acrylic or polycarbonate having transparency is provided. The reason is to allow the inner enclosure 3 and the float 5 to irradiate sunlight, while suppressing heat radiation from the inner enclosure 3 and the float 5 to the outside and preventing dust from entering from the outside.

The water supply / drainage pipe 9 is a pipe for supplying water into the inner enclosure 3 and discharging the obtained hot water. Here, the water supply / drainage pipe 9 may be provided separately for water supply and discharge. In this case, the water supply pipe is connected to a water supply source, and the discharge pipe is connected to a hot water tank, a bathtub, and the like.

[0015]

The water supplied into the inner container 3 through the water supply / drain pipe 9 contacts the inner surface of the inner container 3 and the bottom surface (including the radiation fins 7) and the side surface of the float 5. Here, when the inner container 3 and the float 5 (including the heat collecting fins 6) are radiated from the outside through the outer container 2 and the lid 8, the inner container 3 formed of an infrared radiator is used.
And the float 5 absorbs solar energy with high efficiency and converts it into heat energy. Next, the heat energy is converted into infrared light having a wavelength range of 3 to 200 μm, radiated into water, absorbed by water, and causes a rise in water temperature.
Infrared light in the above wavelength range is absorbed by water to generate frictional energy, and utilizes the fact that it effectively acts on heating of water.

A feature of the structure of the present invention is that the float 5 made of an infrared radiator always floats on the surface of the water, and the solar rays are directly irradiated with sunlight. This is because, as a result of the experiment, the infrared radiator used in the present invention has a lower water temperature rise in the case of absorption of sunlight through water than in the case of direct sunlight. Therefore, in the present invention, the float 5 which always floats on the water surface in order to enlarge the direct solar radiation area
Direct sunlight from the sun.

[0017]

The first effect of the present invention is that drainage is not necessarily required even in a cold season. This is because even if there is volume expansion due to freezing of water, the volume expansion can be absorbed by the vertical movement of the float 5. Even if water is not drained, no damage to the water heater is caused.

A second effect of the present invention is that hot water having a temperature of 50 ° C. or more in summer and 35 ° C. or more in winter can be obtained despite its simple structure. The hot water is a water temperature that can be sufficiently used for a bath except winter, and is a water temperature that can be used as it is for a kitchen only slightly heated in a bath in winter. . With this second effect, it is possible to reduce fossil fuels such as oil, gas and electric power.

A third advantage of the present invention is that the manufacturing cost of the water heater can be reduced because of its simple structure. Specifically, in the case where the amount of water held in the inner container 3 is 250 liters, it can be suppressed to within 50,000 yen, and the performance is inexpensive. The fourth effect of the present invention is that even if scale is adhered to the enclosure 3 and the float 5 due to long-term use, the scale can be easily removed, and slight scale adhesion hardly affects the rise in water temperature. That is. This is due to the fact that heat is absorbed from sunlight without passing through water.

[Brief description of the drawings]

FIG. 1 is a plan view of a solar water heater according to the present invention.

FIG. 2 is a vertical sectional front view of the solar water heater according to the present invention.

[Explanation of symbols]

 1. Solar water heater 2. Enclosure 3. Enclosure 4. Spacer 5. Float 6. Heat collecting fins 7. Radiation fins 8. Lid 9. Supply / discharge pipe 10. Water level

Claims (4)

[Claims] A structure in which a spacer is interposed between an inner surface of an open-top envelope and an outer surface including a bottom surface of the open-top envelope to integrate the outer package and the inner package. A structure in which a float whose upper surface is open so as to be able to move up and down in the vessel and at least two heat collecting fins made of a projecting member having the float set upright or inclined upright on its upper surface is protruded downward from its lower surface. A solar water heater comprising a configuration in which two or more radiating fins are respectively disposed and a configuration in which a lid is disposed on the upper surface of the envelope. 2. A float including an envelope and a heat collecting fin is made of aluminum or an aluminum alloy plate as a core material.
2. The solar water heater according to claim 1, wherein an aluminum alloy plate is used as a clad material, and the surface of the clad material is formed of an infrared radiator having a black oxide film which is naturally colored by anodizing treatment. 3. The solar hot water as claimed in claim 1, wherein the heat collecting fins which are arranged upright or inclined on the float are formed by any one of plate-like, net-like, rod-like, cylindrical and honeycomb-like projecting members. vessel. 4. The solar hot water as claimed in claim 2, wherein the heat collecting fins which are disposed upright or inclined on the float are formed by any one of plate-like, net-like, rod-like, cylindrical, and honeycomb-like projecting members. vessel.