JPS6050342A - solar water heater - Google Patents

Abstract

PURPOSE:To keep balance between repective heat collectors even when the inlet temperature of any of the heat collectors increases extraordinarily so as to enable collecting heat with high efficiency. CONSTITUTION:Both heat collectors 1A and 1B are communicated with each other at the lowermost parts on adjucent side surfaces by means of a communicating pipe 6. In a case where a difference occurs between the temperature at an inlet 3a of one heat collector 1A and the temperature at an inlet 3a at another heat collector 1B, for some reason or other, a difference in the specific gravity occurs, and a similar difference in specific gravity is produced at the lower parts of the heat collectors 1A and 1B. Thus, a water stream is produced through a communication pipe 6, and hence the water temperatures between both heat collectors 1A and 1B are average. For this reason, the degree of increase in the radiation loss is lowered, and the heat collection effeciency is improved.

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a natural circulation type solar water heater.1 [Background Art] Fig. 1 shows a conventional general natural circulation type solar water heater. In the figure, IA and IB are two heat collectors arranged side by side on an inclined roof surface, and a hot water storage tank 2 is installed above the roof in one direction. The two heat collectors IA and IB are connected to a hot water storage tank 2 through a cold water downpipe 3 and a hot water riser pipe 4, respectively.

The principle of natural circulation is that water warmed by solar heat in the heat collectors IA and IB becomes lighter in specific gravity and rises through the hot water upper and outer pipes 4, and cold water with a heavier specific gravity flows from the hot water storage tank 2 through the cold water downcomer pipe 3. It flows into the country. That is, it circulates by thermosiphon. Therefore, heat is collected! The circulation efficiency will be better if the temperature of the inlets 3B of IA and IB is kept low.

However, due to reasons described later, one of the heat collectors IA and I
A phenomenon in which the temperature at the inlet 31 of B increases abnormally, the circulation efficiency decreases, and the total heat extraction amount decreases is often observed. A high inlet temperature of the heat collectors IA and IB reduces circulation efficiency and increases heat radiation loss.

The cause of the increase in the inlet temperature of the heat collectors IA and IB is that, as shown in FIG. 2, for example, the shape of the hot water storage [2] is not symmetrical. In this case, the water iVA is borne by each of the heat collectors IA and IB.

1'B, and as a result, the inlet temperature of the heat collector IB, which has a smaller amount of water to bear, becomes higher than the inlet temperature of the other heat collector IA, resulting in the above-mentioned reduction in circulation efficiency.

In the case of the example shown in FIG. 3, a difference also occurs in the inlet temperature. This example uses heat collectors IA', IB' and hot water storage 112 on both sides of the roof.
The water sucked up by the water conduit 5 passes through the cold water downcomer pipe 3' and flows into the heat collectors IA and IBK. 4' is a hot water riser pipe.

The water guide pipe 5 may also have other functions, in which case the left and right water guide pipes 5 are provided with a difference in thickness.

For example, this may also serve as a water conduit pipe to the lower part of the hot water storage tank 2' for hot water supply.

When there is such a difference in thickness, a difference in circulation resistance (a difference in pressure loss) occurs, and the balance of circulation between the left and right S collectors IA and IB is lost. That is, a difference occurs in the inlet temperatures of the left and right heat collectors IA and 1B.

[Purpose of the invention]

An object of the present invention is to provide a solar water heater that improves heat collection efficiency by reducing variations in inlet temperature between a plurality of heat collectors installed in parallel.

[Disclosure of the invention]

The solar water heater of the present invention has a plurality of heat collectors connected through a communication path.

Embodiment An embodiment of the present invention is shown in FIG. That is, in this solar water heater, the image heat collectors IA and IB are communicated with each other through a communication pipe 6 at the lowermost portions of adjacent side surfaces. The rest of the configuration is the same as the example shown in FIG. 1, so the same parts are given the same reference numerals and the explanation thereof will be omitted.

Operation If for some reason a difference occurs between the temperature at the inlet 3B of one heat collector LA and the temperature at the inlet 38 of the auxiliary heat collector IB, a difference in specific gravity will occur, and the lower part of the heat collectors IA and IB will However, there are also differences in specific gravity. Here, the thin parallel lines indicate the high temperature area,
As shown by the thick parallel lines indicating the low temperature range, if the heat collector IA is at a lower temperature, a flow from the position P shown by the X mark to the position Q occurs through the communication pipe 6, and the heat collector IA, 1 r+
The water temperature is equalized between Therefore, the increase in heat radiation loss of the heat collector IB on the high temperature side is reduced, and the heat collection efficiency is improved.

In other words, the total amount of heat collected is increased by the image heat collectors IA and IB.

FIG. 5 shows another embodiment. In this example, the U-shaped communication pipe 6' collects heat from both sides! l! The lower part of IA, 113 is made to communicate. When configured in this way, the communication pipe 6
Water can be drained by removing the heat collector IA.

It is easy to drain water for cleaning the IB. Also, continuous W
6' is easy to install. The rest is the same as the first embodiment.

Note that the above embodiment includes the hot water storage tank 2 and the heat collector IA.

Although this invention has been applied to a type in which the heat collectors IA' and IB' are installed adjacent to each other, the present invention can also be applied to a type in which the heat collectors IA', IB' and the hot water storage tank 2' are installed separately, as in the example shown in Fig. 3. can do.

〔Effect of the invention〕

The solar water heater of this invention can maintain a balance between each collector and collect heat efficiently even when the inlet temperature of one of the multiple collectors installed in parallel increases abnormally. effective.

[Brief explanation of the drawing]

Fig. 1 is a plan view of a conventional example, Fig. 2 is an explanation of its operation, Fig. 3 is a perspective view of another conventional example, Fig. 4 is an explanatory diagram of the configuration of an embodiment of the present invention, and Fig. 5 is FIG. 7 is a plan view of another embodiment.

Claims (1)

[Claims] A hot water storage tank, a plurality of heat collectors installed below the hot water storage tank and each connected to the hot water tank by a cold water downpipe and a hot water riser pipe, and a communication path that connects these heat collectors with each other. Solar water heater with.