JPH0211836B2 - - Google Patents

Description

Detailed Description of the Invention The present invention provides a heat exchanger tube for air conditioning that can improve the utilization efficiency of underground temperature and improve the strength of the heat exchanger tube by providing fins that rise in a spiral shape around the heat exchanger tube. Regarding structure.

Conventionally, for example, Japanese Utility Model Publication No. 13-5228 discloses,
A cold air generator that has pile-shaped heat transfer tubes buried underground, or an underground heat storage method that uses the underground heat storage area by burying multiple pile-shaped heat transfer tubes as disclosed in Japanese Patent Publication No. 55-44850. Air conditioners that use underground are known, but the thermal conductivity of soil is usually around 1.1Kcal/mH℃ even when it is wet, and about 0.5Kcal/mH℃ when it is dry. Therefore, in conventional air conditioners that utilize underground, such as the cold air generator or underground heat storage method disclosed in each of the above publications, only the underground temperature of the soil near each heat transfer tube is cooled or It could not be used for heat storage and was inferior in efficiency.

The present invention provides an air conditioner that can solve the above problems by providing spiral fins around the heat exchanger tube to increase the contact area with the soil around the heat exchanger tube and improve the heat transfer efficiency between the soil and the heat exchanger tube. For the purpose of providing a heat exchanger tube structure for use in the present invention, an embodiment thereof will be described below based on the drawings.

In Figs. 1 and 2, the heat exchanger tube structure for air conditioning (hereinafter referred to as structure) of the present invention is one in which spiral fins 3 are provided around a heat exchanger tube 2 buried underground. is in the shape of a pile made of cylindrical steel pipe whose lower end is closed by a tapered cone, and the fins 3 surround the heat exchanger tube 2 and extend around the heat exchanger tube 2 from the lower end to the vicinity of the upper end with a relatively small pitch. The fins 3 are formed to have a relatively wide width, and the inner peripheral edges of the fins 3 are welded and fixed to the heat transfer tube 2. The heat exchanger tube 2 is made by drilling a hole in the ground using a boring machine such as an earth auger and having an inner diameter comparable to that of the heat exchanger tube 2, and then lowering the heat exchanger tube 2 while rotating to form the so-called hole. It is buried underground by screwing it into the ground. In the embodiment shown in FIG. 1, the heat exchanger tubes 2 are buried approximately vertically in advance before the building is erected, with the upper ends b remaining slightly under the floor near the foundation a of the building. A tube body 4 hangs down.

The tube body 4 is held concentrically within the heat exchanger tube 2 by a lid body 5 attached to its upper end b, and is formed slightly shorter than the heat exchanger tube 2 so that its lower end A communication portion 4a for fluid return is formed at c. In this embodiment, the pipe body 4 is made of a material with low thermal conductivity, and has a fluid passage 6a and a fluid passage 6b which are insulated inside and outside. The lid 5 has a flat cap shape, and its lower surface fixes the upper end of the tube 4, and the upper surface is connected to a conduit 7 that communicates with the tube 4 and hence the fluid flow path 6b. The conduit 7 passes through, for example, the cloth foundation a, the wall d, etc., and opens toward the room R at the outlet 9 of the wall d.
Further, the lid body 5 is further connected with a conduit 9 that communicates with the fluid flow path 6a, and the conduit 9 is connected to a discharge port 10a of an electric fan 10 such as a centrifugal blower to which a filter device 11 is connected on the inflow side. do.

Then, the electric fan 10 is operated and the filter device 1
The liquid air filtered from 1 is sent through conduit 9 to fluid flow path 6a. The air is transferred to heat transfer tube 2
The inner surface of the pipe body 4 is lowered to perform heat exchange with the underground temperature of, for example, 15°C, and is folded back at the communication part 4a to return to the pipe body 4.
It ascends through the internal fluid flow path 6b. The tube body 4 is made of a heat insulating material, so that the heat-exchanged air is discharged into the room R through the conduit 7 while being thermally insulated. Further, the heat exchanger tube 2 is provided with fins 3 surrounding it in a spiral manner,
Therefore, it is possible to improve the thermal conductivity between the heat transfer tubes 2 and the surrounding soil, and as a result, even when operating for a long period of time, the underground heat transfer can be made more efficient, and the geothermal heat of a wide range of soil can be utilized. It enables heat exchange with the air, and when the outside temperature is high, such as in summer, for example, the underground temperature is used to cool the air, making it possible to cool the room R. Also, as in the above embodiment, the filter device 1 is installed under the floor.
When air is taken in from 1, underfloor air whose temperature is several degrees lower than the outside air temperature can be used, further improving air conditioning efficiency.

In addition, 15 in the figure is attached to the lid body 5 and is for discharging the dew condensation water e stored in the lower end part a of the heat exchanger tube 2.
Drain pipe 16 leading from the outside to the lower end c of the heat transfer tube 2
This is a drainage pump that is installed in the system, and is activated at any time to prevent condensed water from stagnating.

3 to 5 show other embodiments of the present invention;
What is shown in the figure is to fill a heat exchanger tube 2 with a refrigerant w, lower a tube body 4 spirally rotating into the refrigerant w, and connect a conduit 9 that opens under the floor to the tube body 4 and a chamber R. By providing a conduit 7 that communicates with the conduit 7, and by providing an electric fan 10 at the tip of the conduit 7, it is possible to discharge air cooled, for example, into the room by the refrigerant w that exchanges heat with the underground temperature. , the heat capacity of the heat exchanger tubes 2 can be increased by the refrigerant w.
In addition, FIG. 4 shows that the refrigerant w is pumped into the chamber R by a pump P.
The refrigerant w is circulated between the refrigerant w
A spirally rotating tube body 4 is installed inside the tube body, and the fluid flowing inside the tube body 4 can be circulated and distributed by a pump P to a heat exchanger 17 installed indoors, and each heat transfer tube A fin 3 is eventually provided around the fin 2 .

As described above, the structure of the present invention involves burying a heat transfer tube in the ground, air-conditioning the room by means of a fluid that passes through the inside and turns around at the bottom, and at the same time, the heat transfer tube is provided with fins that surround the heat transfer tube and rise in a spiral shape. Because they are integrally installed, the heat exchanger tube increases the contact area with the soil, increases heat conduction with the soil, and improves the heat exchange efficiency between the underground temperature and the heat exchanger tube. Improve air conditioning efficiency. Furthermore, the heat exchanger tube is reinforced by the fins, making it easier to bury it underground and reducing the wall thickness of the heat exchanger tube, further improving the heat exchange efficiency between the fluid inside the heat exchanger tube and the soil. Furthermore, the heat exchanger tube can be screwed in using the fins, which helps simplify the embedding work.

In addition, in the structure of the present invention, the fins may be provided over the entire length of the heat transfer tube, or may be provided around a part of the heat transfer tube such as the lower end thereof, which is divided into a plurality of pieces. In addition, the device of the present invention can be used as a cold air extraction device for extracting cold air in the summer, and can also be used as a heating device in the winter by making use of the underground temperature, which is higher than the outside air temperature, and by using a subheater device.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing one embodiment of the present invention, and FIG.
The figure is a partially cutaway perspective view illustrating a heat exchanger tube, and FIGS. 3 to 5 are diagrams showing other embodiments. 2...Heat transfer tube, 3...Fin.

Claims (1)

[Claims] 1. A pile-shaped heat exchanger tube that is buried underground and can be used to air-condition a room by means of a fluid that passes through the inside and turns back at the lower end, and is cylindrical in shape and closed at the lower end with a tapered cone section, surrounding the pile-shaped heat transfer tube. A heat exchanger tube structure for air conditioning, in which a helically rising fin is provided integrally around the heat exchanger tube in advance, and a lid body is attached to the upper end of the heat exchanger tube to which a tube body through which fluid flows is attached.