JPS5852140B2 - Solar heat collector tubes and solar heat collectors - Google Patents

Description

[Detailed Description of the Invention] Solar heat collecting devices using vacuum glass tube type heat collectors, that is, vacuum double heat collecting pipes, can be roughly divided into two types depending on how they are used. There are two types: a pass-through type that takes out the hot water that comes out, a natural circulation type that circulates using the thermosiphon phenomenon, where water becomes lighter and rises as it warms, and a circulation pump that uses a forced circulation pump. It can be divided into forced circulation type.

The vacuum double collector tube used for the former is easy to drain the water to be heated and does not stagnate inside, so there is less risk of freezing and damage, whereas the heat collector tube used for the latter is bottomed. Since it is a pipe, it is necessary to take measures such as installing some kind of anti-freezing method and using it in an inverted position (with the bottom side facing up), but the heat collection effect is significantly superior to that of a through-type pipe. Circulating heat collectors using bottomed heat collecting tubes tend to be more widely adopted, so a simple measure to prevent freeze damage has been desired for circulating heat collectors.

Additionally, vacuum glass tube heat collectors have the disadvantage of being easily broken, so if they break, the broken tube must be replaced, but with conventional heat collectors, in such a case, the entire device must stop functioning. For example, there is an inconvenience in that replacement work cannot be performed, and a countermeasure for this problem has been desired.

The present invention has been developed based on the fact that a heat collecting device using a vacuum glass tube type heat collector is more expensive than a model with a plastic heat collecting part or a closed pump type heat collecting device, and has an excellent heat collecting effect. In addition to making it possible to apply simple antifreeze measures to the bottomed vacuum glass tube type heat collector, and even in the unlikely event of damage, it will be possible to continue using it without stopping all functions. The present invention relates to a solar heat collecting tube and a solar heat collecting device that are intended to facilitate maintenance when the heat collecting pipe is damaged or replaced, and one embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a partially omitted plan view of one unit of the heat collecting device of the present invention, with a medium passage 1 provided with an inlet passage for the medium to be heated and a discharge passage for the heated medium placed in the center. The solar heat collecting tubes 2 are arranged horizontally and parallel to each other, with 12 solar heat collecting tubes 2 on each side on both the left and right sides.First, the solar heat collecting tubes 2 will be explained as shown in Fig. 2. , so-called bottomed transparent glass tubes 3, 4 of different diameters with the other end open.
are stacked concentrically, and at the open ends of both the inner and outer pipes 3 and 4,
A glass lid 1 in which two holes 5 and 6 are formed with a required distance apart is hermetically fused and the ends thereof are closed to seal the mutual space 8 between the inner and outer tubes 3 and 4. , the pressure in the space is reduced to form a vacuum double main pipe.

Reference numeral 9 denotes a selective absorption film formed on the surface of the inner glass tube 3, which is a thin film having the characteristics of high absorption rate for light waves with relatively short wavelengths and low emissivity for heat rays.

One of the two holes 5, 6 is for the inlet of the medium, and the other 6 is for the outlet, but in the embodiment, both the holes 5, 6 are on the line passing through the center of the lid The holes were drilled at maximum intervals.

However, the holes 5 and 6 depend on how the two tubes are stacked, such as whether the inner and outer tubes 3 and 4 are stacked concentrically as described above, or eccentrically stacked based on the installation specifications of the solar heat collection tube. Accordingly, they are formed on a line that passes through the center of the closure lid 1, or on a line that does not pass through the center, and their position is not specified.

In FIG. 5, γ' is a protrusion formed around the medium inlet hole 5 and outlet hole 6 of the lid T for opening and closing the elastic valves 15 and 16 described later.

Reference numeral 10 indicates small protrusions formed by bulging out in the centripetal direction at multiple locations near the bottom of the outer glass tube 4 in order to maintain a gap between the inner glass tube 3 and the outer glass tube 4. The inner glass tube 3 may be formed by bulging outward at a proper position, or a similar effect may be achieved by using a suitable gap maintaining member such as a spring.

As shown in Fig. 5, the medium passage 1 is formed by dividing an inlet passage 11 for the medium to be heated and an outlet passage 12 for the heated medium into two stages, upper and lower, with 12 passages on each side of the medium. The openings 13 and 14 of the closing lid γ close the open ends of both the inner and outer tubes 3 and 4 constituting the solar heat collecting tube 2, respectively.
6 is laterally opposed to the openings 13 and 14, but when connecting the solar heat collecting pipe 2 to the medium passage 1,
A lid IT made of rubber with excellent weather resistance and heat resistance and a spring plate 18 equipped with elastic valves 15 and 16 for opening and closing the hole 5°6 between the inlet passage 11, the discharge passage 12, and the lid γ. Hold and touch.

Note that the elastic valve 15α6) is normally closed in one position as shown in FIG. 6, but when pressed from the left direction in the same figure at the position indicated by the arrow, it opens as shown in FIG. The inside of the medium passage 1, that is, the inlet passage 11 and the discharge passage 12, can be communicated individually, and the spring plate 18 prevents the tube from breaking when the pressing force on the solar heat collecting tube 2 is released, especially when the tube is damaged. In order to actively remove the remains of the heat collecting tube 2 from the medium passage 1, the elastic force pushes the remains of the heat collecting tube 2 in the left direction (opposite direction to the arrow) in FIG. It is possible to instantly release the pressing force on the valve 15α6), for example,
When the outer glass tube 4 of the solar heat collecting tube 2 is broken, the above-mentioned pressing force on the elastic valve 15α6) is actively released by the spring plate 18, and at this time, the elastic valve 15 (16) is closed together. It is something that performs an action.

19 is a water conduit pipe for guiding the medium to be heated toward the bottom of the inner glass tube 3 from the side of the open elastic valve 15; 20 is a heat insulating material covering the periphery of the medium passage 1;

The medium passage 1 and the solar heat collecting pipe 2 formed as described above...
are arranged in an orderly manner as shown in Fig. 1 by a rectangular construction frame 21, but the bottom portions of the solar heat collecting pipes 2, which are connected to the medium passage 1 as described above, are arranged as follows. It is supported by an erection frame 21.

Reference numeral 22 denotes a holder fixed to the left and right sides of the construction frame 21, and the upper surface near the bottom of the solar heat collecting tube 2 is supported by a semicircular arc portion 23 formed on the upper part, and the bottom part of the solar heat collecting pipe 2 is attached to the end of the holder 22. The tip of the screw 24 screwed in the direction is screwed onto the supporter 26 of the conical holder 25 that supports the bottom of the tube from the second fixed (right) direction, and by turning the screw 24, the conical shape is formed. The holder 25 is made horizontally movable, so that the solar heat collecting tubes 2 are sandwiched and supported between the medium passage 1 and the holder 25, and the first
With the horizontal arrangement as shown in the figure, solar heat collector tubes 2...
- are supported in parallel on the construction frame 21.

Note that instead of using the tightening force of the screws 24, it is also possible to use the pressing force of a spring to press the bottoms of the solar heat collecting pipes 2.

Between the solar heat collecting tubes 2 in which curved plates 2T shown in Fig. 3 are arranged in horizontal rows, sunlight reflection that commonly covers the front lower surface and rear lower surface of the adjacent heat collecting tubes 2゜2. The curved surface of the board is set taking into account the angle of incidence of sunlight in summer and the angle of incidence of sunlight in winter, but in order to prevent rainwater from accumulating on the same board surface, adjoining solar reflectors are installed. A gap 28 is provided between 2γ and 27.

Figures 7 and 8 are a side view and a plan view showing the outline of the device of the present invention installed on the roof. The units A, A, etc. adjacent to each other are connected to the medium inlet pipes 291 and 292 and the medium discharge pipes 301 and 302 provided above and below the medium passage 1 of each unit t-A with appropriate pipe joints (
(not shown), and the respective ends of the downward water supply pipe 292 and the discharge pipe 302 of the lowest unit A are closed, and the pipes are arranged so that the medium enters from above and flows upward again.

Note that a storage tank (not shown) for the heated medium is provided on the roof or on the ground within easy reach, and is connected to the inlet pipe 291 and the discharge pipe 3.
Connect to 01.

Next, the effect in the case of natural circulation will be explained based on the above embodiment.

When the present invention is used as a hot water device, tap water is placed in advance into a storage tank provided at the top of the roof.

Water that exits the tank and enters the inlet passage 11 from the water pipe 291 passes through the open elastic valve 15, is guided to the water guide pipe 19, and enters the inner glass tube 3 of the solar heat collecting pipe 2.

The water that entered the inner glass tube 3 flows through both the inner and outer glass tubes 3,
It will be warmed by the action of solar heat passing through 4,
The conduction and convection of solar heat received by the inner glass tube 3 of the solar heat collector tube 2 is caused by the selective absorption film 8 formed on the surfaces of both tubes 3 being sealed in the vacuum space between the inner and outer tubes 3 and 4. Due to the selective absorption film's high absorption in the solar radiation spectrum (visible range) and low emissivity in the thermal radiation spectrum (infrared range), it absorbs more than 90% of sunlight without escaping heat. , heats the water in the inner glass tube 3.

When the water changes to a certain amount of hot water, it becomes lighter and the discharge passage 12
The hot water is discharged from the hot water and rises toward the storage tank, and the water in the tank descends and enters the inner glass tube 3 through the inlet passage 11, and this process is repeated to circulate the hot water within the heat collecting device. .

In this way, the water (hot water) in the inner glass tube 3 enters the discharge passage 12 through the open elastic valve 16 through the hole formed in the lid 61 of the solar heat collecting tube 2, and is stored from the discharge passage 12. The water (hot water) in the storage tank flows toward the tank and enters each heat collection pipe 2 from the same water supply channel 11 through the elastic valve 15 side, and is circulated every time the water temperature in the heat collection pipe 2 rises. The temperature of the hot water in the system rises uniformly in each part, and eventually reaches 80-100℃.
You can get hot water as high as 1.

The hot water obtained in this way can be used directly for hot water supply, but it can also be temporarily stored in a storage tank for later use.

Next, a case will be described in which one or more of the solar heat collecting tubes 2 should be damaged.

In the heat collecting device of the present invention, all the heat collecting pipes 2 have elastic valves 15.1
6 to the medium passage 1, the elastic valve 1
5.16 opens when the solar heat collecting tube 2 is pressed from the left direction (right direction for the right side tube) in FIGS. 2 and 5,
It closes when the pressure on both tubes 2 is removed, so when only the outer tube 4 of the solar heat collecting tube 2 breaks, or when the inner tube 3
If both the inner and outer tubes break at the same time, the elastic valves 15 and 16 of the protrusions γ' and γ' formed around the medium inlet hole 5 and the outlet hole 6 of the lid 1 which are fused to the open ends of both the inner and outer tubes 3 and 4. There is no pressing force on the

That is, when the outer glass tube 4 breaks, the lid 1 moves toward the holder 25 due to the elastic force of the spring plate 1B, and the elastic valve 15
．． Release the force that causes 16 to open.

Therefore, at this time, the elastic valves 15 and 16 are momentarily closed,
Since the water (hot water) in the medium passage 1 will not flow in, all the circulation systems connecting the normal solar heat collection pipes 2 will continue to function as they are, regardless of some damage. You can get hot water by twitching.

Next, when replacing the broken solar heat collector tube 2 with a new one, loosen the screw 24 at the part that supports the broken tube, move the holder 25 backward, and reduce the distance between the holder 25 and the medium passage 1. , expand the new tube 2 until it can be inserted easily,
In this state, install the new pipe 2 and tighten the screw 24 again.

In this way, with the holder 25, the new solar heat collecting pipe 2
When supported, the lid T presses the elastic valves 15 and 16 again to open the volume valves, so that water (hot water) flows into the new pipe.

Furthermore, if there is a risk of freezing in the winter, the water in all the heat collecting devices can be easily drained by opening the discharge pipe 302 of the lowest unit t-A.

The present invention has been described above based on the examples, but the solar heat collecting tube of the present invention has a selective absorption film 9 on the surface having characteristics of large heat absorption in the solar radiation spectral range and low emissivity in the thermal radiation spectral range. This is a vacuum double-front type solar heat collecting tube in which an inner glass tube 3 with a broken bottom and a transparent outer glass tube 4 are stacked concentrically or nearly concentrically with a necessary vacuum space interposed between them. In this step, the open ends of the inner and outer glass tubes 3 and 4 are closed and sealed with a glass lid 1 to connect the two tubes, and the iron lid γ is provided with an inflow hole and a discharge hole for the medium at a required distance apart, Since the protrusions 7' for opening the valve body provided on the medium passage 1 side are provided around both holes, the holes 5 and 6 formed in the lid 7 clearly define the medium inlet and outlet. The perforated lid 7 can provide the same effect as a pipe using a U-shaped pipe, but when a U-shaped pipe is used, depending on the direction of the pipe, the water inside may be naturally drained. However, according to the heat collecting tube of the present invention, even if the plurality of holes 5 and 6 are not installed vertically in line, if there is even a slight difference in height between the two holes 5 and 6, the solar heat collecting tube can be fixed. It has the effect of being able to perform its functions as well as facilitating natural discharge.

Moreover, since the opening end of the tube is closed with the lid 1 having the plurality of holes 5 and 6, the heat collecting tube of the present invention can be used even if the installation location of the device is not inclined or has an angle of inclination. A lid 7 that closes the open end of the heat collecting pipe even if it is loose
Since it is possible to create a height difference between the medium inflow hole 5 and the discharge hole 6 by rotating the heat collecting tube, the medium can be adjusted by assuming the direction of the virtual line connecting the inflow hole 5 and the discharge hole 6 Once the position of the opening on the passage 1 side is determined, the heat collecting pipe of the present invention can be used not only in a forced circulation type heat collecting device but also in an overflow type heat collecting device in a place where there is no slope or only a slight slope. It has the advantage that it can be easily adopted as a heating device.

Next, the solar heat collecting device of the present invention includes a bottomed inner glass tube 3 whose surface is covered with a selective absorption film having characteristics of large heat absorption in the solar radiation spectral range and low emissivity in the thermal radiation spectral range, and a transparent inner glass tube 3 with a bottom. The outer glass tubes 4 are stacked concentrically or nearly concentrically with a necessary vacuum space between them, and the open ends of the inner and outer glass tubes are closed and sealed with lids, and a medium inflow hole is provided in the iron lid. 5 and a discharge hole 6 are provided at a required distance, and a solar heat collecting pipe 2 is provided with a protrusion γ' for opening a valve body around both holes, a medium inlet passage 11 and a discharge passage 12. A valve body that opens when pressed by the protrusion 1' of the solar heat collecting pipe 2 is provided in the connecting portion 13° 14 of the solar heat collecting pipe which is opened in a direction perpendicular to the medium inlet/outlet path 11.12. 15,
16, and the inflow hole 5 and the discharge hole 6 of the intermediate pipe 2 are connected to the connection part of the solar heat collecting pipe of the medium path 1.
are removably and individually attachable, and on the side facing the medium passage 1, there is a solar heat collecting tube in the direction in which the valve bodies 15 and 16 are suppressed to open when the solar heat collecting tube 2 is attached to the medium passage 1. Since a support device 25 for the bottom of the solar heat collecting pipe 2 is provided to press the bottom of the solar heat collection pipe 2, if any of the solar heat collection pipes 2 breaks, the valve 15 provided between the inlet pipe 11 and the discharge pipe side 12 The valve 16 provided between the heat collecting pipe 2 and the valve 16 is released from the pressing force of the heat collecting pipe 2 and closes instantaneously.
Since the openings 13 and 14 at the still positions can be blocked and the medium flowing in the medium passage 1 can be immediately prevented from flowing out, the heat collecting action by the other heat collecting pipes 2 . . . will not be interrupted until the repair is completed. Even if the solar heat collection tube 2 is missing in a part of the device, it can be used continuously, if a slight decrease in heat collection ability is ignored.

Further, if rubber or other elastic valves are used for the valve bodies 15 and 16, there is no need to provide a special seal member and there is no need for a seal between the solar heat collection pipe and the valve body.

Moreover, according to the invention, the medium channel 1 is arranged longitudinally,
The solar heat collecting pipes 2 are arranged horizontally in parallel to the mutually divided inlet passage 11 and discharge passage 12 of the passage, and storage tanks (not shown) are connected to the inlet passage 11 and the discharge passage. If it is provided above the upper end of the tank 12, the medium can be naturally circulated, or alternatively, the storage tank can be provided at a low place and the medium can be forcedly circulated by a circulation pump.

Moreover, since the inlet passage 11 and the discharge passage 12 are oriented in the vertical direction,
Opening these flow channels allows the medium inside the heat collecting device to flow out naturally, and has the effect of easily preventing freeze damage during extremely cold weather.

Furthermore, in the present invention, the bottom of the solar heat collector tube 2 is provided with a support device that serves both to support the open tube and to open the valve body provided in the medium passage 1, so that when the solar heat collector tube 2 is damaged or replaced. It has the advantage of easy maintenance.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 is a partially omitted plan view of the heat collecting device, and FIG. 2 is the same as FIG. 1.
- Partially longitudinal front view taken along line ■ Figure 3 is Figure 1 Figure 1
- Partial longitudinal side view taken along line 1, Figure 4 is Figure 1 I
A partially vertical side view cut along the line V-IV, Figure 5 is an enlarged vertical front view of the center of the medium passage, Figure 6 is a vertical side view of the elastic valve, and Figure 7 is a side view of the elastic valve installed on the roof. , FIG. 8 is a plan view as well. 1...Medium passage, 2...Solar heat collection tube, 3...Inner glass tube, 4...Outer glass tube, 5, 6... ... Hole, 7 ... Closing lid, 8 ... Selective absorption membrane, 11 ... Medium feed path, 12 ... Medium discharge path, 13. 14...
...Opening, 15, 16...Valve, 18...
...Spring plate, 19...Pipe, 21...Erection frame.

Claims (1)

[Scope of Claims] 1. An inner glass tube with a bottom and a transparent outer glass tube whose surface is treated with a selective absorption film having characteristics of high heat absorption in the solar radiation spectrum range and low emissivity in the thermal radiation spectrum range. In a vacuum double-front type solar collector tube, which is stacked concentrically or nearly concentrically with a required vacuum space between them, the open ends of the inner and outer glass tubes are closed and sealed with a glass lid. Both the inner and outer pipes are connected, and the iron lid has a medium inflow hole and a medium discharge hole separated by the required distance, and a protrusion around the circumference for opening the valve body on the medium passage side. Solar heat collector tube. 2. A bottomed inner glass tube whose surface is broken with a selective absorption film having characteristics of high heat absorption in the solar radiation spectral range and low emissivity in the thermal radiation spectral range and a transparent outer glass tube are placed between them. The inner and outer glass tubes are stacked concentrically or nearly concentrically with a vacuum space in between, the open ends of the inner and outer glass tubes are closed and sealed with a lid, and the iron lid is provided with an inlet and an outlet hole for the medium at a required distance apart, and a solar heat collection tube having a protrusion for opening a valve body around the circumference, and a solar heat collection pipe having a medium inlet and outlet path and opening in a direction perpendicular to the medium inlet and outlet path. A medium passage is provided in the connecting part with a valve body that opens when pressed by the protrusion of the solar heat collecting pipe, and the inflow hole and the discharge hole of the intermediate pipe are attached and detached to the solar heat collecting pipe connecting part of the medium passage. A bottom portion of the solar heat collecting tube is provided on the side facing the medium path and presses the bottom of the solar heat collecting tube in a direction that suppresses the valve body to open when the solar heat collecting tube is installed in the medium path. A solar heat collector equipped with a supporting device.