JPS61259090A - Heat pipe - Google Patents

Abstract

PURPOSE:To provide a heat pipe adapted to be used for preventing corrosion of heat due to air, water soil or the like, drawing up geothermal heat and collecting solar heat by providing a plastic corrosion preventive layer on the outer circumference of a container made of an aluminum pipe. CONSTITUTION:A container consists of an aluminum pipe 1 sealing therein a working liquid 2 such as flon or the like and having both ends hermetically closed. On the whole outer periphery, the container is provided with a plastic corrosion preventive layer 3 formed by extrusion of polyvinyl chloride, polyethylene or the like. Further, as a modification of the heat pipe is used a type in which a heat insulating layer 4 is provided on the outer periphery of a central pipe except a heat absorbing evaporating portion and a heat discharging condensing portion on both ends of the heat pipe, and a corrosion preventive plastic layer 3 is formed on said heat insulating layer 4 or another type in which the heat insulating layer 4 is formed on the corrosion preventive layer 3 and further a protective layer 5 made of a plastic material similar to the corrosion preventive layer 3 is further provided on the outer periphery of the heat pipe. Thus, the heat insulating layer 4 is protected from the water content under the ground and in the atmosphere, and the lowering of the heat insulating effect due to heat absorption is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a heat pipe using an aluminum pipe as a container.

(Prior art and problems to be solved) Pumping up geothermal heat in winter to melt snow on roads and roofs of houses, prevent freezing of railway points, prevent utility pole stays from breaking due to ice and snow, etc. without using energy. Moreover, heat pipes are effective in always requiring no maintenance, and heat pipes are also useful as collectors of solar heat.

Steel pipes with galvanized outer surfaces are used as containers for such heat pipes in consideration of economic efficiency and robustness, but steel pipes are generally of a fixed length and have a length that can be transported by truck. The length of pipes is up to 5.5 m, and longer pipes require special means of transport and are straight pipes, making them difficult to handle.

In addition, since steel pipes are made to a fixed length, it is not possible to manufacture long pipes and cut them to the required length for use.Container materials must be made one by one, and furthermore, they must be bent on site. For example, it was difficult to match the shape of the stay of a utility pole.

On the other hand, aluminum pipes are suitable for use as containers for heat pipes because they are compatible with fluorocarbon-based hydraulic fluids and have appropriate flexibility and robustness. It was difficult to use due to the problem that it was easy to use.

(Means for solving the problems) The present invention solves the above problems of aluminum pipes,
It provides a heat pipe suitable for geothermal pumping and solar heat collector, and its feature is that it has a plastic anti-corrosion layer on the outer periphery of the container made of aluminum pipe.

(Embodiment) FIGS. 1 to 5 all show longitudinal cross-sectional views of embodiments of the heat pipe of the present invention, and the same symbols represent the same parts.

Figure 1 shows the basic structure of the present invention, in which a plastic material such as polyvinyl chloride or polyethylene is extruded over the entire outer circumference of an aluminum pipe (1) container with a working fluid such as fluorocarbons sealed inside and sealed at both ends. A plastic anti-corrosion layer (3) is provided.

As the aluminum pipe (2), an extruded aluminum pipe or a corrugated aluminum pipe obtained by applying corrugation processing to this pipe is used.

Figure 2 shows the first modification of the heat pipe of the present invention, in which a heat insulating layer is placed on the outer periphery of the aluminum pipe (1) in the central heat insulating part excluding the heat absorption evaporation part and the heat dissipation condensation part at both ends of the heat pipe. (4), and a plastic anti-corrosion layer (
3). Also, Fig. 3 shows a second modified structure, in which the plastic corrosion protection Im(3) of the heat pipe shown in Fig. 1 is used.
A heat insulating layer (2) is provided in the central heat insulating part on top of the heat insulating layer (2), and a protective layer made of the same plastic material as the plastic anti-corrosion layer (3) is provided on the outer periphery of the heat insulating layer (2). ! FfA■ is provided. The material for this heat insulating layer (2) is not particularly limited, but foamed plastic material is preferred from the viewpoint of heat insulating and cushioning properties. In addition, a heat insulating layer (4) is provided inside the plastic anti-corrosion layer (Fig. 2), or a third
Plastic corrosion protection as shown! If it is provided outside II of (3), by further providing a protective layer ■ of plastic material on top of it, heat insulation J! ! (Protects Φ from moisture in the ground and the atmosphere, and prevents the insulation effect from decreasing due to heat absorption.

Figure 4 shows the third modified structure of the heat pipe of the present invention, in which the heat pipe has a plastic anti-corrosion NA (3
), a plastic anti-corrosion layer (3') is locally provided on top of it to form a double structure and serve as a heat insulating layer.

The heat pipes shown in FIGS. 1 to 4 described above have a plastic anti-corrosion layer (2) on the entire outer periphery of the aluminum pipe (1), so both the endothermic evaporation section and the heat dissipation/condensation section at both ends are insulated. It is suitable for applications that do not require a relatively large amount of heat to be pumped, such as preventing snow from sticking to utility pole stays, and in fact it is better not to pump too much heat at once.

Figure 5 shows a fourth modified structure of the heat pipe of the present invention, in which the plastic anti-corrosion layer (3) is applied only to the central insulation part, and the heat absorption evaporation part and the heat radiation condensation part at both ends are made of aluminum pipes. (1) Corrosion-resistant treatment IjM■ such as Teflon treatment, alumite treatment, epoxy resin coating, or enamel coating is provided on the surface. In this case, the plastic anti-corrosion layer (3) and anti-corrosion treatment! Wrap anti-corrosion tape or apply anti-corrosion paint to the boundary of J■ to make it watertight.

(Effects of the Invention) According to the heat pipe of the present invention, since a plastic anti-corrosion layer is provided on the aluminum pipe, the problem of corrosion due to external conditions, which was the only drawback of aluminum pipe containers, is improved, and the heat pipe has a long lifespan. It is possible to easily manufacture a heat pipe that is flexible in length by continuous extrusion, and a heat pipe that is highly economical can be obtained.

Furthermore, when a plastic anti-corrosion layer is provided over the entire circumference of the aluminum pipe, it is possible to reduce the amount of heat absorbed and released, allowing for the slow pumping of geothermal heat over a long period of time.

[Brief explanation of the drawing]

1 to 5 each show a longitudinal sectional view of an embodiment of the heat pipe of the present invention. DESCRIPTION OF SYMBOLS 1... Aluminum pipe, 3;... Plastic anti-corrosion layer, 4... Heat insulation layer, 5... Protective layer, 6... Corrosion-resistant treatment layer.

Claims (5)

[Claims] (1) A heat pipe characterized by having a plastic anti-corrosion layer on the outer periphery of a container made of an aluminum pipe with a working fluid sealed inside. (2) The heat pipe according to claim 1, wherein the aluminum pipe is corrugated. (3) The heat pipe according to claim 1 or 2, wherein the working fluid is fluorocarbon. (4) The heat pipe according to any one of claims 1 to 3, characterized in that a heat insulating layer is provided in the heat insulating section at the center of the heat pipe. (5) A plastic anti-corrosion layer is provided only in the central insulation part of the heat pipe, and corrosion-resistant treatment is applied to the outer surfaces of the aluminum pipe in the heat absorption evaporation part and heat dissipation condensation part at both ends. The heat pipe according to items 1 to 4.