JPH04350463A - Solar energy collector - Google Patents

Abstract

PURPOSE:To provide a solar energy collector using header pipes which do not break even if it is freezed, whose production cost is low, in which possibility of water leakage is very little and which is free from blue water problem. CONSTITUTION:Header pipes 6 and 7 are made of a glass fiber reinforced resin obtained by blow-molding nylon 66 mized with 20wt.% of E glass fibers so that their tensile extension is 7%.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solar heat collector comprising a plurality of vacuum solar heat collectors connected by header pipes.

0002

[Prior art] Conventionally, vacuum type solar collectors have been
Some have a structure in which a thin heat transfer pipe with a heat collecting plate is placed inside a long transparent glass container that is kept in a vacuum, and others have a structure in which a large volume of water is pumped up and stored to collect solar heat. There is a structure with a structure in which

[0003] Such vacuum type solar heat collectors are usually arranged in parallel on the roof of a building, etc., and one or both ends of each collector are connected to a header pipe, so that the heat medium of each collector is Water is supplied to the pipes and inside the water storage tank, and hot water is extracted to the outside of the heat collector.

0004

[Problems to be Solved by the Invention] However, in the header pipe of the vacuum type solar heat collector as described above, water flows inside the header pipe at a maximum flow rate of 10 l/min or more, and moreover, in a system directly connected to the water supply, , 0.8 Kg/cm2 pressure is applied, so it is required to have the strength to withstand it.

[0005] For this reason, metals such as copper, which have high pressure resistance, have traditionally been used as materials for header pipes, but such metal header pipes can be damaged if the water inside them freezes in the winter. The problem is that it is easy to do.

[0006] That is, the coefficient of volumetric expansion when water freezes is
It is about 9%, whereas that of metals such as copper is 9%.
%, and even if the water inside the header tube expands due to freezing, the header tube itself expands to a smaller degree than the water, making it more likely to be damaged.

[0007] In addition to the above-mentioned problems, it is difficult to manufacture metal header pipes by integral molding, and usually each part is molded once and then welded or brazed together. As a result, manufacturing costs increase, and
Furthermore, there is a risk that water may leak from the joints during use. Furthermore, when a header tube made of copper is used, the metal element of copper is eluted into the water while water is stored inside the header tube, causing the so-called blue problem.

An object of the present invention is to provide a solar heat collector using header pipes that will not be damaged even when frozen, has low manufacturing costs, has little risk of water leakage, and will not cause green water problems. be.

[0009]

[Means for Solving the Problem] The present inventor uses a glass fiber reinforced resin that contains a predetermined amount of glass fiber and is integrally molded so that the tensile elongation is 3% or more as a material for the header pipe. The inventors have found that the above object can be achieved and propose the present invention.

That is, the solar heat collector of the present invention is a solar heat collector in which a plurality of vacuum type solar collectors each having a heat collector disposed inside a transparent long glass container are connected by a header tube. The header tube is characterized in that it is made of a glass fiber reinforced resin containing 10 to 30% by weight of glass fiber and integrally molded so as to have a tensile elongation of 3% or more.

[0011]

[Function] The glass fiber reinforced resin used in the present invention contains 10% by weight or more of glass fibers, so it has the desired strength, that is, a strength that can withstand pressure of 0.8 kg/cm2 or more, and has low tensile elongation. Since it is 3% or more, it has a volume expansion coefficient of about 9% or more. In other words, the volumetric expansion coefficient is equivalent to the cube of the tensile elongation, and if the tensile elongation is 3% or more, the volumetric expansion coefficient is 9.27% or more. Therefore, even if the water inside the header pipe expands, , the header tube will not expand further and be damaged.

However, if the glass fiber content exceeds 30% by weight, the moldability of the resin will deteriorate and the tensile elongation will decrease, which is not preferable.

As the glass fiber of the present invention, ordinary E-glass can be used, and as the resin, for example, nylon-based, polyphenylene sulfite (PPS)-based, and polyacetal (POM)-based resins are suitable.

When connecting the header pipe of the present invention to a vacuum type solar collector, rubber hoses, couplings, screws, etc. can be used. Further, as a manufacturing method for the header pipe, ordinary blow molding and injection molding are suitable, and by adopting these molding methods, integral molding becomes possible.

[0015]

EXAMPLES The present invention will be explained in detail below based on examples.

FIG. 1 is a plan view of a solar heat collector according to the present invention, and FIG. 2 is a perspective view of the main parts thereof.

In the drawing, the vacuum solar collector 1 is
It mainly consists of a transparent long glass container 2 with both ends open, and a copper water storage tank 3 coaxially arranged inside the container. Both ends of the water storage tank 3 are open, and the outer surface thereof is coated with a selective absorption membrane. A gap exists between the glass container 2 and the water storage tank 3, and the gap has a predetermined degree of vacuum [for example, 10-4 Torr].
] is maintained.

One end of a copper connecting pipe 4 is welded to the opening of the water storage tank 3 of each vacuum solar collector 1, and the other end of the connecting pipe 4 is connected to the upper header pipe by a copper coupling 5. 6 and the lower header pipe 7. One end of a sealing fitting 8 is sealed to the opening of each glass container 2, and the other end of the sealing fitting 8 is welded to the connecting pipe 4.

Each header tube 6, 7 is made of nylon 66,
Made from blow-molded glass fiber reinforced resin containing 20% by weight of E-glass fibers, its tensile elongation is 7%.
It is.

The solar heat collecting device described above is installed on the roof of a building or the like at a predetermined angle, and when the water supply valve is opened, the water supplied from the upper header pipe 6 flows through the upper connecting pipe 4. The hot water flows into the interior of the water storage tank 3 through the water storage tank 3, is kept there until it warms up for a certain period of time, and is then taken out as hot water from the lower header pipe 7 via the lower connecting pipe 4 by opening the hot water tap in the bathroom or kitchen. Thereafter, the same amount of water as the hot water taken out is supplied from the upper header pipe 6 to the inside of the water storage tank 3 via the upper connecting pipe 4.

[0021] The above tensile elongation value is based on ASTM
It was determined based on the measurement method of D-638.

[0022]

As described above, in the solar heat collecting device of the present invention, the header tube contains glass fibers in an integrated manner so as to contain 10 to 30% by weight of glass fibers and have a tensile elongation of 3% or more. Since it is made of reinforced resin, it will not be damaged even if the water inside it freezes, and the manufacturing cost is low, there is little risk of water leakage, and there is no need to worry about green water problems.

[Brief explanation of drawings]

FIG. 1 is a plan view of a solar heat collector according to the present invention.

FIG. 2 is a perspective view of the main part of FIG. 1;

[Explanation of symbols]

1 Vacuum type solar collector 2 Glass container 3 Water storage tank 6 Upper header pipe 7 Lower header pipe

Claims (1)

[Claims] 1. A solar heat collecting device in which a plurality of vacuum solar heat collectors each having a heat collector disposed inside a transparent long glass container are connected by a header pipe, wherein the header pipe is made of glass. A solar heat collecting device characterized in that it is made of a glass fiber reinforced resin containing 10 to 30% by weight of fibers and integrally molded so as to have a tensile elongation of 3% or more.