JPS6012992Y2 - solar heat collector - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a solar heat collection device used in a solar heat utilization system.

Recently, the use of solar heat has attracted attention as a part of energy saving measures, and various heat collection devices are being developed and developed.

Among these solar heat collectors, vacuum type solar heat collectors are heat collectors with copper heat collector pipes inside a glass airtight container (
This device is equipped with heat collecting fins, and the inside of this glass container is evacuated to create a high vacuum, which heats the heat medium flowing into the heat collecting pipe. There are plates that absorb mainly infrared rays from sunlight and conduct this heat to the heat medium in the heat collecting pipe, and the vacuum space inside the glass container acts as a heat insulating layer to prevent heat dissipation from the heat collecting plate. What to do? J) et al. - For example, when the heat medium is water, the heat collecting performance is so excellent that it can be heated up to 80 to 90°C.

This has the advantage that it can be used not only for indoor heating and hot water supply for baths and kitchens, but also for cooling when combined with an absorption refrigerator.

However, in addition to the heat collecting plate and the heat collecting pipe, the glass container houses a heat collecting plate support that supports the heat collecting plate and the heat collecting pipe between the inner wall of the glass container. This has a great negative impact on the efficiency of solar heat collectors.

That is, the support is made of a wire made of phosphor bronze or the like, and its central part is fixed to the heat collecting pipe with silver brazing, and its five ends are elastically applied along the inner wall of the glass container. being touched.

Therefore, part of the heat in the heat medium heated in the heat collection pipe is dissipated to the outside air through the heat collection pipe, the support and the glass container, and the heat medium in the heat collection pipe is There was a problem that increased heat loss.

Furthermore, since the support is fixed to the heat collecting pipe by silver soldering, the silver soldering releases impurities during long-term use.

In particular, when heated to high temperatures, more impurities are released, so the degree of vacuum inside the glass container gradually decreases during long-term use, resulting in a decrease in the insulation function; There were also problems that led to a decrease in heat collection efficiency.

This idea was devised based on these circumstances, and its purpose is to prevent heat loss of the heat medium in the heat collection pipe and decrease in heat collection efficiency caused by the above-mentioned heat collection plate support. Our purpose is to provide thermal equipment.

An embodiment of this invention will be described below with reference to FIGS. 1 to 4.

1 in the figure is a glass airtight container, and this glass:
- The container 1 is constituted by, for example, a glass tube 2 made of borosilicate glass whose both ends are hermetically closed with metal end caps 3a, 3b.

This glass container 1 has, for example, an outer diameter of 50 to 100 m4 and a total length of 2000 to 260 mm.A heat collecting pipe 4 is inserted into the glass container 1 and positioned approximately on the tube axis.

The heat collecting pipe 4 constitutes a passage for a heat medium, and is made of a copper pipe or the like having excellent heat conduction.

The heat collecting pipe 4 passes through the end cap 3av3b in an airtight manner, and is airtightly connected to one end cap 3a via an exhaust pipe 5, as shown in FIG. ing.

The exhaust pipe 5 has a concentric double pipe structure so as to constitute the heat collecting pipe 4 and the exhaust space 6. One end is hermetically joined to the end cap 3a, and the other end is connected to the end cap 3a. It is hermetically joined to the outer surface of the heat collecting pipe 4.

An exhaust pipe 7 is connected to this exhaust pipe 5.

The exhaust pipe 7 is connected to a vacuum pump when evacuating the inside of the container 1, and is sealed when a predetermined exhaustion is completed.

A bellows 8 is integrally formed on the exhaust pipe 5 so that the thermal expansion and contraction of the heat collecting pipe 4 is absorbed by the bellows 8.

: A heat collecting plate 9 is housed in the container 1.

The heat collecting plate 9 is formed of a plate having excellent thermal conductivity such as aluminum, and the heat collecting pipe 4 is connected to the central part of the plate.
It is closely bonded to the outer surface of the

Note that the heat collecting pipe 4 and the heat collecting plate 9 are joined by caulking or the like.

The heat collecting plate 9 has a surface facing the sun, and a selective absorption film (not shown) is provided on this surface.

) This selective absorption film absorbs well in the wavelength region of sunlight, but has a property of emitting only a small amount in the infrared wavelength region.

The heat collecting plate 9 integrally joined to the heat collecting pipe 4 as described above is supported by heat collecting plate supports 10 at multiple locations along the tube axis direction of the container 1. There is.

Each heat collector plate support 10 is made of a thin plate made of phosphor bronze or the like, and one end thereof is attached to the end of the heat collector plate 9 with a fixing device, such as a bolt/nut 11, and the other end is a glass tube. It is elastically abutted against the inner surface of 2.

Further, the length from each heat collecting plate support 70% heat collecting plate 9 to the point where it comes into contact with the inner surface of the glass tube 2, ie, 1 shown in FIG. 4, is set to be at least 10 m++ or more.

Therefore, these heat collecting plate supports 10 hold the heat collecting pipe 4 on the tube axis of the container 1.

Note that 12... is each heat collecting plate support 10 and heat collecting plate 9.
It is a heat insulating member inserted between the heat sink and the heat sink, and is made of, for example, a mica plate or ceramics that has low thermal conductivity.

In this way, the mica plate 12 and bolts are attached to the heat collecting plate 9.
The operation of the heat collecting device attached via the nut 11 will be explained.

When sunlight passes through the glass container 1, it irradiates the heat collecting plate 9.

Since a selective absorption film is formed on the surface of the heat collecting plate 9, it can absorb the wavelength region of sunlight well and prevent the emission of infrared wavelengths.

Therefore, the temperature of the heat collecting plate 9 increases.

The heat of the heat collecting plate 9 is conducted to the heat collecting pipe 4, and therefore heats the heat medium flowing into the heat collecting pipe 4.

Further, during such a heat collecting action, the inside of the glass container 1 is maintained at a high degree of vacuum, so that heat dissipation from sunlight absorbed by the heat collecting plate 9 is prevented.

As a result, the heat absorbed by the heat collecting plate 9 is effectively conducted to the heat collecting pipe 4, so that the heat collecting efficiency is high.

Since each of the heat collecting plate supports 10 is attached to the heat collecting plate 9 instead of the heat collecting pipe 4, a part of the heat amount of the heat medium heated in the heat collecting pipe 4 is transferred to each heat collecting plate. It will not be released into the outside air via the support 10.

Therefore, heat loss of the heat medium in the heat collecting pipe 4 caused by each heat collecting plate support 10 can be prevented.

Note that by attaching each heat collecting plate support 10 to the heat collecting plate 9, it is possible that the heat of the heat collecting plate 9 is dissipated to the outside air via each heat collecting plate support 10. By setting the length 1 from the heat collecting plate 9 of 10 to the point where it comes into contact with the inner surface of the glass tube 2 to be at least 1- or more, each heat collecting plate support that comes into contact with the inner surface of the glass tube 2 is set. The temperature difference between the temperature at the end of the tool 10 and the temperature at the tube wall of the glass tube 2 can be made to be almost nonexistent, so that the heat collection efficiency of the heat collection plate 9 does not decrease.

As a trial, I used a heat collecting plate support with a thickness of 0.3 m, a width of 5 strips, and 1 = 2.
- When formed of phosphor bronze, the temperature at the end of each heat collecting plate support 10 on the heat collecting plate 9 side was approximately 1ω°C, but the end temperature of each heat collecting plate support 10 on the glass tube 2 side was temperature of about 30'
C, and the temperature difference between the end temperature on the glass tube 2 side and the temperature of the outside air can be made to be almost nonexistent.

In addition, since each heat collecting plate support 10 is attached to the heat collecting plate 9 with bolts and nuts 11, the bolts and nuts can remain inside the glass tube 2 even during long-term use, unlike the conventional case of fixing with silver solder. No impurities are released from Nut 11.

Therefore, since the degree of vacuum can be maintained within the glass tube 2 and its heat insulating function can be maintained over a long period of time, a decrease in the heat collection efficiency can be prevented.

Note that this invention is not limited to the one embodiment described above.

For example, the heat collector plate support is not necessarily made of a thin plate of phosphor bronze, but is instead made of a stainless steel wire 13 with low thermal conductivity, as shown in FIG. 9 may be disposed through the ends thereof, and the central portion thereof may be fixed with a fixing device, for example, a rubber body 14 having heat insulating and heat resistant properties.

Therefore, according to such a configuration, two heat collecting plate supports can be combined into one.

Furthermore, even when the heat collecting plate 9 is formed of a thin plate according to one embodiment, as shown in FIGS. 6 and 7, one end of the heat collecting plate 9 is supported by one heat collecting plate support 15, or Alternatively, by supporting the front side and the back side of the heat collecting plate 9 with one heat collecting plate support 16 respectively, two heat collecting plate supports can be combined into one.
can be made into

As explained above, according to this invention, since the heat collecting plate support is attached to the heat collecting plate insulated from the heat collecting plate, the heat of the heat collecting plate is not transferred to the heat collecting plate support. Heat loss dissipated to the outside air through the heat collecting plate support is reduced, and the heat medium in the heat collecting pipe can be effectively heated.

Furthermore, since the heat collecting plate support is attached via a fixture, impurities will not be released from the fixture even during long-term use.

Therefore, the heat insulating function of the glass airtight container can be maintained over a long period of time, so that a solar heat collecting device can be obtained which can prevent a decrease in its heat collecting efficiency, and the effect is great.

[Brief explanation of the drawing]

Figures 1 to 84 show one embodiment of this invention, with Figure 1 being a perspective view of the whole, Figure 2 being a cross-sectional view showing the structure of section 1 in Figure 1, and Figure 3 showing the main parts. FIG. 4 is a sectional view taken along the line IV--IV in FIG. 1, and FIGS. 5 to 7 are sectional views of main parts showing modified examples of the heat collecting plate support. 1... Glass airtight container, 4... Heat collection pipe, 9... Heat collection plate, 10... Heat collection plate support, 11... ...Bolts and nuts (fixing devices)
.

Claims (1)

[Scope of Claim for Utility Model Registration] A glass airtight container whose inside is evacuated, a heat collection plate that is housed in the glass airtight container and is equipped with a heat collection pipe that serves as a passage for a heat medium, and the heat collection plate. A heat collecting plate support is provided which is interposed between the inner wall of the glass airtight container and supports the heat collecting plate, and the heat collecting plate support is insulated from the heat collecting plate and attached by a fixing device. A solar heat collection device characterized by: □－