JPS5932166Y2 - closed switchboard - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a closed power distribution board that prevents condensation on electrical equipment housed in a housing.

Conventionally, there has been a closed switchboard as shown in FIG.

In Figure 1, 1 is the housing of the closed switchboard, 2.3 is the ventilation hole provided at the bottom and top of the housing 1, 4 is the heater provided inside the housing 1, and 5 is the heater housed inside the housing 1. It is an electrical device.

In the closed switchboard configured as described above, the heater 4 constantly generates heat, and the outside air that enters the housing 1 through the vent 2 at the bottom is transferred to the upper part by natural convection generated around the heater 4 as shown by the arrow. and is discharged to the outside of the housing 1 from the upper ventilation port 3.

As a result, the air inside the housing 1 is constantly ventilated, and the air temperature inside the housing 1 follows the temperature change of the outside air with almost no time delay. Since it is constantly heated, the temperature is always about 5 degrees higher than the outside temperature.

The temperature of the electrical equipment 5 inside the casing 1 also changes approximately according to changes in the air temperature inside the casing 1, and the temperature of the electrical equipment 5 is either equal to the air temperature inside the casing 1, or in the case of an electrical equipment that generates heat. The temperature is higher than the air temperature inside the housing 1.

For example, if the daily average outside temperature is 20°C, it will drop to around 12°C at night, and the relative humidity will be 75°C at night.
If the temperature is excellent, the dew point will be 15°C.

In this case, if the temperature of the electrical equipment 5 inside the housing 1 is 15 degrees Celsius or lower, condensation will occur, but as mentioned above, the air inside the housing 1 is about 5 degrees higher than the outside air. Therefore, the temperature is approximately 17°C, and electrical equipment 5 is located in case 1.
Since the temperature is often higher than the air inside, there is no condensation.

However, in the conventional closed switchboard as mentioned above, the heater needs to be constantly energized, which requires energy from electricity, and the position of the vents causes air to stagnate inside the housing. There is often a problem that the air heated by the heater does not flow through these areas and the temperature is low, resulting in dew condensation.

This idea was made to solve the above-mentioned problems, and by equipping the housing with a heat exchanger that uses heat storage material, it is possible to save energy and provide a highly reliable closed switchboard. The purpose is then.

Examples of this invention will be described below with reference to the drawings.

In FIG. 2 showing an embodiment of this invention, 1 is a housing of a closed distribution board, 2 and 3 are vents, and 5 is electrical equipment, which are substantially similar to those shown in FIG. 1 described above. It is.

Reference numeral 6 denotes a heat exchanger housed in the housing 1, and the heat exchanger 6 includes a heat pipe 8 equipped with a fin 7 and a heat storage container 10 containing a heat storage material 9. One side part 8a is inserted into the heat storage material 9, and the other side part 8b is piped along the side wall of the housing 1, and is installed in the lower part of the housing 1 facing the vent 2.

Note that the heat storage material 9 is made of water, paraffin, etc.
Further, the heat pipe 8 has an inner wall lined with a material having a capillary action such as sintered metal or wire mesh, and after the inside is evacuated, an operating body such as fluorocarbon or water is sealed.

In the closed switchboard configured as described above, when the outside air temperature during the day is higher than the temperature of the heat storage material 9 of the heat exchanger 6, the outside air entering the housing 1 through the vent 2 at the bottom of the housing 1 is heated through the fins. 7
The liquid working body in the side part 8b outside the heat storage material 9 of the heat pipe 8 is heated and evaporated through the heat pipe 8, and this vapor flows to the side part 8a inserted into the heat storage material 9 of the heat pipe 8,
It is cooled and condensed by the low-temperature heat storage material 9, and at the same time releases the heat of condensation to the heat storage material 9.

The condensed and liquefied working body is returned to the side 8b outside the heat storage material 9 by the capillary action of the material having capillary action.

Through such circulation of the operating body, the heat storage material 9 is heated by the outside air and stored therein, and the air inside the housing 1 is cooled by removing heat.

When the outside temperature drops at night, heat is released from the heat storage material 9 to the air inside the housing 1 via the heat pipe 8 due to the operation of the heat pipe 8 in the opposite manner to that described above, and this air heated.

Due to the above-described operation, the heat storage material 9 has the effect of making the temperature change of the air inside the casing 1 smaller than the temperature change of the outside air, and even when the outside air temperature is low and condensation is likely to occur, the temperature of the air inside the casing 1 remains constant. Since the temperature is high, no condensation occurs on the electrical equipment 5 inside the housing 1.

Further, since the side portion 8b of the heat pipe 8 outside the heat storage material 9 can be made to have an arbitrary length, uneven ventilation within the housing 1 can be reduced and reliability can be increased.

FIG. 3 shows another embodiment of this invention. In this embodiment, the fins 7 are arranged on the inside of the casing 1 of the heat exchanger 6, that is, on the side 8b of the heat pipe 8 outside the heat storage material 9. A blower fan 11 is installed so as to

In this way, the air inside the housing 1 is forcibly moved by the drive of the blower fan 11, so that the unevenness of ventilation inside the housing 1 is reduced. Since the heat transfer at 8b is improved, the heat exchange efficiency between the heat storage material 9 and the air inside the housing 1 is improved.

FIG. 4 shows still another embodiment of this invention, in which a second heat pipe 12 is provided to exchange heat between the outside air and the heat storage material 9 of the heat exchanger 6. If the portion 12b of this heat pipe 12 that is in contact with the outside air is located below the portion 12a that is inserted into the heat storage material 9, the second heat pipe 120 will be more affected by capillary action due to the action of gravity. Due to the small force, the liquid working body in the heat pipe 12 will cause the portion 1 in the heat storage material 9 to
2a is refluxed to the part 12b that contacts the outside air,
It stops flowing in the opposite direction, that is, the heat storage material 9 is removed from the outside air.
Since heat is carried to the casing 1 but difficult to be carried in the opposite direction, more heat can be stored in the heat storage material 9, and the heat storage material 9
It is possible to increase the amount of heating of the air inside and improve the dew condensation prevention effect.

In FIGS. 3 and 4, the same reference numerals as in FIG. 2 indicate the same or corresponding parts.

As explained above, this invention is equipped with a heat exchanger that uses heat storage material, so it is possible to save energy, and it is also possible to reliably prevent condensation on electrical equipment inside the housing, making it reliable. This has the effect of providing a sealed power distribution board with high performance.

[Brief explanation of drawings]

Figure 1 is a side sectional view showing an example of a conventional closed switchboard;
The figures are side sectional views showing one embodiment of this invention, Figures 3 and 4.
The figures are side sectional views showing different embodiments of this invention. 1... Housing, 2, 3... Vent, 5.
...Electrical equipment, 6...Heat exchanger, 8...
... Heat pipe, 9 ... Heat storage material, 10.
...Heat storage container, 11 ...Blower fan, 1
2...Second heat pipe. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Scope of claim for utility model registration] l In a closed switchboard containing electrical equipment in a housing,
A closed power distribution board characterized in that the housing is equipped with a heat exchanger that exchanges heat between the air in the housing and the heat storage material in the heat storage container. 2. The closed switchboard according to claim 1, wherein the heat exchanger is configured to exchange heat between air and a heat storage material via a heat pipe. 3. The heat exchanger is a heat exchanger provided with a blower fan in the heat exchange part inside the casing of the heat pipe.
Closed switchboard as described in section. 4 The heat exchanger has a second heat pipe for exchanging heat between the outside air and the heat storage material, and the part of the heat pipe that is in contact with the outside air is located below the part in the heat storage material. A closed switchboard according to claim 2 of the utility model registration claim.