JPS5924344B2 - Heat pipe type solar collector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a solar heat collector (hereinafter simply referred to as a collector) surrounding a heat pipe, and particularly relates to a collector in which a heat pipe and a solar heat collector are integrally molded.

A heat pipe type collector generally has a configuration as shown in FIG.

In the figure, reference numeral 1 denotes a cylindrical glass tube with a bottom, into which a copper heat pipe 2 whose outer envelope is made of a metal material and whose surface is coated with a selective absorption film 7 is inserted. , glass tube 1 and heat pipe 2 are sealed (
It's true.

Glass tube 1 has an exhaust pipe (as shown) connected to the other end.
・The inside 5 is kept in a vacuum state by being evacuated from the inside (not shown) and then tipped off.

4 in the figure indicates a tip-off portion.

Note that the support spring 6 is attached to the outside of the heat pipe 2 in order to reduce the moment in the sealing part 3 and the internal stress inside the glass tube in this part (
It's true.

The heat pipe 2 is attached to the header 8 by providing a hole on the side of the header 8 for good heat exchange.
As shown in the figure, the hole is usually made to pass through the heating part 9 of the heat pipe 2 and come into contact with the heated fluid 10 flowing through the belly button 8.

The collector as described above transmits received solar heat to the heated fluid 10 extremely efficiently due to the good heat transfer coefficient of the heat pipe 2 and the vacuum state inside the glass tube 1. The disadvantage is that the diameter of the heat pipe 2 serving as the heat receiving section is smaller than that of the glass tube 1, and the effective light receiving area is smaller than the light receiving surface of the glass tube 1.

Therefore, recently, as shown in Fig. 2, a flat heat collecting plate 11 having a width approximately the same as the inner diameter of the limb tube 1 is provided inside the glass tube 1, and the heat pipe 2 is caulked into the concave groove 12 of this plate 11. A collector was proposed in which the effective light-receiving area was increased by crimping.

However, in such a collector, the sunlight is absorbed by the heat collecting plate 1.
If the sunlight is incident perpendicularly to the glass tube 1, most of the sunlight passing through the glass tube 1 will be captured by the heat collecting plate 11, but if the sunlight is incident obliquely to the heat collecting plate 11, the glass Since only a portion of the sunlight passing through the tube 1 can be captured by the heat collecting plate 11, there is a drawback that - the sunlight whose altitude changes during the day cannot be effectively captured at all times.

Moreover, such a collector has a heat collecting plate 11 and a heat pipe 2.
Not only is there a loss in heat conduction because they are separate parts, but also the heat collecting plate 11 and the heat pipe 2 must be crimped one by one during manufacturing, which complicates the manufacturing process and increases costs. Then, there were some drawbacks.

The present invention has been made to eliminate all the drawbacks of the collectors mentioned above, and one embodiment of the present invention will be described in detail below with reference to the drawings.

Note that parts that are the same as those in the prior art are designated by the same reference numerals.

In FIGS. 3 and 4, reference numeral 2 denotes an aluminum heat pipe whose heat receiving portion 2a is inserted into the glass tube 1. In FIG.

Reference numeral 13 denotes a hollow cylindrical solar heat collector formed along the axial direction so as to surround the outer periphery of the heat receiving part 2a, and is integrally molded with the heat pipe 2 by aluminum extrusion molding at the same time as shown in FIG.・Ru.

As described above, since the heat pipe 2 including the solar heat collector 13 is integrally molded by extrusion molding of aluminum, it can be easily obtained even if the cross-sectional shapes of the heat collector 13 and the heat pipe 2 are slightly complicated.

In addition, since both ends 14 and 14 of the heat pipe section 2 remain open in the extrusion-molded state, it seems that the heat pipe section 2 in this state can be used as it is as a water pipe for heat collection rather than as a heat pipe. However, when water passes through it, corrosion and electrolytic corrosion occur on the inner surface of the pipe, so it cannot normally be used as a water pipe.

However, when used as a heat pipe, aluminum should not be corroded or caused other disadvantages (e.g. generation of non-condensable gas) as a working fluid (for example, if fluorocarbons, ethanol, ammonia, etc. are used, corrosion, There is no problem of electrolytic corrosion, and the working fluid is simply injected through the opening 14 and the opening 14 is sealed (.), so manufacturing is also simple.

In addition, as shown in FIG. 3, the heat pipe portion on the left side from E may be made of aluminum extrusion, and the heat pipe portion on the right side from E may be made of a copper pipe, and both may be welded.

In this way, the weather resistance and heat resistance of the heating section 9 are improved, and the sealing with the glass tube 1 becomes easy.

Reference numeral 15 denotes a reflecting portion formed in the lower half of the inner circumferential surface of the glass tube 1, and in FIG. It is what you do.

This reflective part 15 may be made using vacuum processing technology such as aluminum vapor deposition, or may be made of a thin metal plate adhered to the inner surface of the glass tube, but if the reflectance is high, the heat collector with a heat pipe can be used. It is necessary for the body 13 to have the function of a reflecting mirror.

Further, a spring 6 is welded to the heat collector 13 with a heat pipe and supports the heat collector 13 with a heat pipe so that the sealed portion is not forced.

As shown in FIG. 4, the cylindrical heat collector 13 has its center offset above the center of the glass tube 1 so that it can efficiently receive the reflected light from the reflecting section 15.

Note that the heat collector 13 may be provided with a slight vertical gap 16 in its axial direction as shown in FIG. , because it always captures sunlight with a width corresponding to its diameter, - the daily light collection efficiency is greatly improved compared to the one shown in Figure 2.

Furthermore, since the reflective portion 15 is provided, the light beam passing through the side of the heat collector 13 can also be made to enter the heat collector 13,
The heat collection efficiency can be further improved.

In this case, since the heat collector 13 is cylindrical, the rate of capturing reflected light is much higher than that of a flat plate, which helps improve the heat collection efficiency.

In addition, the solar heat concentrator 13 is not subjected to selective absorption film treatment (・
It serves to recapture the radiant heat from the lower surface 17 of the heat pipe 2 and prevent heat loss, thereby further improving the light collection efficiency.

Furthermore, since the solar heat collector 13 is integrated with the heat pipe 2, the thermal contact is better and manufacturing is easier than when the solar heat collector 13 is a separate body as shown in FIG.

Another effect is that when the selective absorption film I is coated on the surface of the heat collector with heat pipe 130, the coat may be easily and uniformly formed.

In other words, the above-mentioned coating work is done by the chemical conversion treatment method or the spunter method, but in that case, it is easier to form a coating on a cylindrical shape than on a plate shape because the electric field is distributed more uniformly, and the coating is also uniform. It grows on the vine.

As shown above, in the above embodiment, in the solar heat collector, at least the heat receiving part of the heat pipe located in the vacuum container is made of aluminum, and the aluminum solar heat collecting part extends along the axial direction on the outer periphery of the heat receiving part. It is characterized by its body being integrally molded.

Generally, there is a heat collecting pipe (through which water passes) in the collector (a copper pipe is used for the heat pipe due to its weather resistance and corrosion resistance, but as in the present invention, it is located inside a vacuum container). When at least the heat-receiving part of a heat pipe is made of aluminum, the weather resistance of the heat-receiving part is sufficient because it is located inside a vacuum container, even though aluminum is inferior to copper in terms of weather resistance under normal conditions. If the hydraulic fluid to be sealed is made non-corrosive, it will have sufficient corrosion resistance without any special processing and can be put to practical use.

In other words, aluminum can be used as a forming material for the heat propagation means connecting the light receiving part and the heated part in the collector only when the light receiving part is located in a vacuum container as in the present invention, such as a heat pipe. be.

Further, since aluminum is used, it is easy to process, and the solar heat collector can be integrally molded by extrusion molding, and its manufacture is extremely simple compared to the one shown in FIG.

According to the present invention, it is possible to obtain a collector which has extremely high heat collection efficiency and is easy to manufacture.

[Brief explanation of the drawing]

The first figure is a vertical cross-sectional view of a conventional heat pipe type collector, the second figure is a cross-sectional view of a heat pipe type collector, the third figure is a vertical cross-sectional view of a rotor collector according to the present invention, and the fourth figure is a third figure. FIG. 5 is a cross-sectional view of main parts of another embodiment. 1 glass tube, 2: heat pipe, 2a: heat receiving part, 1
3: Solar heat collector.

Claims (1)

[Scope of Claims] 1. A heat pipe type solar collector in which a heat receiving part of a heat quiz is inserted into a heat insulating container and a heating part of the heat pipe is provided in a heated part, which comprises the heat pipe,
A heat pipe type solar heat collector that is made by integrally molding a solar heat collector that extends in the axial direction on the heat receiving part of the heat pipe. 2. The heat pipe type solar heat collector according to claim 1, wherein the heat receiving part of the heat pipe including the solar heat collector is made of aluminum. 3. The heat pipe type solar collector according to claim 2, wherein the heat receiving part of the heat pipe including the solar heat collector is integrally molded by extrusion molding of aluminum. The heat pipe type solar heat collector according to claim 2 or 3, wherein the working fluid is fluorocarbons. 5. The solar heat collector has a cylindrical shape so as to surround the heat receiving part of the heat pipe. A heat pipe type solar heat collector according to claim 1, 2, 3, or 4, characterized in that the solar heat collector is formed in a cylindrical shape. A heat pipe type solar collector according to claim 5. 7. Claims 1, 2, 3, and 4, wherein the heat insulating container is a cylindrical transparent body.
The heat pipe type solar collector according to item 5 or 6. 8. Claims 1, 2, 3, 4, 5, 6, 7, or 8, characterized in that the heat-insulating container is a transparent vacuum container. The described heat pipe type solar collector.