JPH10292966A - Electronic refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the heat radiating efficiency of an electronic refrigerator by concentrating heat radiating holes to the upper edge and the lower edge of a back surface plate for forming natural convection between the back surface plate and a thermally insulated box body without forming holes at the middle part of the back surface plate. SOLUTION: A thermally insulated box body 2 is filled with thermally insulating material 4 between an outer box 3 and an inner box in an electronic refrigerator 1. Heat radiating holes 22 of the sizes narrower than those of fingers are formed on the back surface upper part of the outer box 3 not to interrupt the ascending convection caused by the heat radiation from a cooling system 10. A back surface plate 20 is for preventing the contact of heat radiating fins 9 to a high temperature part and provided with heat radiating holes 23 on the upper edge, heat radiating holes 24 on the lower edge and no holes at the medium part between them. The heat radiating holes 23 and 24 are formed with slits narrower than those of fingers and the total of the opening area of the heat radiating holes is not less than the drafting area of a duct formed by the back surface of the thermally insulated box body and a back surface plate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic refrigerator using a natural convection to cool an inside of a refrigerator by an electronic cooling system using a Peltier element for cooling.

[0002]

2. Description of the Related Art As a characteristic of an electronic refrigerator, a Peltier element is used as a cooling means, and there is no mechanical noise and vibration as compared with a compressor type. Have been.

However, in recent years, the destruction of the ozone layer of specific CFCs has become a problem, and switching to alternative CFCs has also been performed at a rapid pace in refrigerators. Against this background, electronic refrigerators using a Peltier element as cooling means are being reviewed because they have nothing to do with ozone depletion. Demand is gradually increasing even in ordinary households, and a second refrigerator is required to have a larger capacity and a freezer.

A conventional example is disclosed in, for example, Japanese Patent Application Laid-Open No. 64-84084. However, the present invention is directed to an electronic refrigerator that employs a heat radiation system by natural convection without using an electric fan for cost reduction.

Hereinafter, the above-described conventional electronic refrigerator will be described with reference to the drawings. FIG. 4 is a rear perspective view of a conventional electronic refrigerator.

[0006] 1 is an electronic refrigerator, 2 is an insulated box,
The space between the outer box 3 and the inner box (not shown) is filled with a heat insulating material 4. On the back side of the heat insulating material 4, a hole 5 communicating with the inside of the storage
Are provided, a heat absorbing plate 6, a Peltier element 7, a heat radiating plate 8,
A cooling system 10 including a radiation fin 9 and the like is arranged. A heat absorbing plate 6 made of an aluminum material or the like having good heat conductivity is arranged on the inside of the storage corresponding to the hole 5.
Is adiabatically sealed.

A Peltier element 7 is placed on the outside air side of the heat absorbing plate 6, that is, at a position corresponding to the inside of the hole 5, in a heat conductive manner.
On the surface of the Peltier element 7 opposite to the surface on which the heat absorbing plate 6 is mounted, a heat radiating plate 8 made of a material having good heat conductivity such as aluminum is heat conductively mounted. The heat radiating plate 8 has a heat radiating fin 9 for radiating heat, and the heat radiating fin 9 is configured to be located on the back surface of the heat insulating box 2.

Next, the operation of the cooling system 10 will be described. When a direct current is applied to the Peltier element 7, the Peltier element 7 is previously set to absorb heat from the heat absorbing plate 6 side and dissipate heat to the radiating plate 8 side, so that heat is absorbed from the heat absorbing plate 6 side. Dissipates heat to the heat sink 8 side. Therefore, the heat in the refrigerator is transferred to the heat absorbing plate 6, the Peltier element 7, and the radiating plate 8 in this order, and further radiated to the atmosphere through the radiating fins 9.

Reference numeral 20 denotes a back plate for preventing the cooling system 10 from coming into contact with a high-temperature portion.
In order to allow heat to escape, a heat radiating hole 21 large enough to prevent human fingers from entering is provided on the entire back plate. Also,
A heat radiating hole 22 large enough to prevent a human finger from entering is provided in the upper rear part of the outer case 3 so as not to hinder the upward convection due to heat radiation from the cooling system 10.

[0010]

However, the above-mentioned conventional structure has the following problems since the heat radiation holes are provided on the entire back plate. FIG. 2 is a schematic view of a heat radiation path of the conventional electronic refrigerator. In the conventional structure, since the heat radiation holes 21 are provided on the entire surface of the back plate 20, heat is radiated by natural convection in an open space. In addition, there is a problem in that heat is circulated in a circulating manner such that hot air radiated from the lower stage of the heat radiating hole 21 is re-inhaled from the upper stage, and the wind speed is not obtained, so that the efficiency of heat radiation is low. This problem can be solved to some extent by forming a duct between the back surface of the heat-insulating box and the wall surface, depending on the distance (A) from the wall surface on the back side of the refrigerator at the time of installation, and obtaining a chimney effect. However, the effect depends on the distance (A) from the wall surface on the rear side of the refrigerator.

[0011]

SUMMARY OF THE INVENTION The present invention solves the conventional problems and provides an electronic refrigerator having high heat radiation efficiency. That is, as in claim 1, a cooling system,
In an electronic refrigerator of a heat dissipation system based on natural convection composed of a back plate and a heat insulating box, the heat dissipation holes of the back plate are concentrated at the upper end and the lower end of the back plate, and the middle is closed.

Further, as in claim 2, the number of holes is small enough to prevent human fingers from entering the middle of the back plate and not more than 10% of the area closed so as not to hinder the chimney effect. Is arranged.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to an embodiment shown in the drawings. The same components as those in the related art are denoted by the same reference numerals, and detailed description thereof will be omitted.

FIG. 1 is a rear perspective view of an electronic refrigerator according to an embodiment of the present invention. 1 is an electronic refrigerator, 2 is a heat insulating box, and a heat insulating material 4 is provided between an outer box 3 and an inner box (not shown).
Is filled. A heat radiating hole 22 large enough to prevent a human finger from entering is provided in the upper rear part of the outer case 3 so as not to hinder the upward convection due to heat radiation from the cooling system 10. Reference numeral 20 denotes a back plate for preventing contact with a high-temperature portion such as the radiation fin 9. The back plate 2
0 is provided with a heat radiation hole 23 at the upper end and a heat radiation hole 24 at the lower end,
It has a configuration that blocks the middle.

The heat radiating hole 23 is formed by a slit having such a size that a human finger cannot enter. The total opening area of the heat radiating hole is equal to the ventilation area of the duct formed by the back of the heat insulating box and the back plate. Shall be equal to or greater than The heat radiating hole 24 is also formed by a slit having a size that does not allow human fingers to enter, and the total opening area of the heat radiating hole is equal to the ventilation area of the duct formed by the back of the heat insulating box and the back plate. Above.

The effect of the above configuration will be described with reference to FIG.

FIG. 3 is a schematic view of a heat radiation path as viewed from the side of the box of the electronic refrigerator of the present invention. Since the heat radiation holes are concentrated at the upper and lower ends of the back plate 20 and the middle is closed,
A duct is formed by the back of the heat insulating box and the back plate. Therefore, convection occurs between the two planes parallel to the vertical direction, and the hot air radiated from the radiation fins 9 rises between the two wall surfaces as shown by the arrow in the figure. Due to the chimney effect, the cool air is reliably supplied from the heat radiating holes 24 in the lower rear plate, and the heat radiating holes 2 in the upper rear plate are formed.
The heat radiation holes 3 and the heat radiation holes 22 are exclusively used for heat radiation, so that heat radiation circulation is smoothly performed. In addition, since the wind speed increases, the radiation fins 9
The heat radiation efficiency increases.

Further, by setting the distance (B) between the back surface of the heat-insulating box and the back plate so as to optimize the ventilation area of the duct formed by the back surface of the heat-insulating box and the back plate, the rear surface of the refrigerator A high heat radiation effect can always be maintained irrespective of the distance (A) from the side wall surface.

FIG. 5 is a rear perspective view of an electronic refrigerator according to another embodiment using the present invention. At least one work hole 25 is provided in the middle portion of the back plate 20 so that a human finger cannot enter. If the total opening area of the working holes 25 is 10% or less of the area covering the heat radiation hole in the middle part of the back plate, the chimney effect according to the present invention is not lost, and a high heat radiation effect can be maintained. Thereby, work such as attaching the screw 11 to the inside through the work hole 25 can be performed so that the screw does not protrude from the rear surface.

[0020]

As described above, the present invention relates to an electronic cooling system using a Peltier device, a back plate, and an electronic refrigerator of a heat dissipation system by natural convection composed of a heat insulating box body. Is concentrated on the upper and lower edges of the back plate, and the middle is closed.Therefore, there is no waste of heat circulation such that heat is radiated from the lower heat radiating hole and the hot air is re-inhaled from the upper heat radiating hole. No heat generation occurs, and the heat dissipation efficiency can be increased by increasing the ventilation speed by the chimney effect. The distance between the back of the heat-insulating box and the back plate (B)
Is optimized, it is possible to always maintain a high heat radiation effect irrespective of the distance (A) from the wall surface on the rear side of the refrigerator.

Further, as in the second aspect, holes are provided in the middle of the back plate so as not to allow a finger of a person to enter, and the total opening area is 10% or less of the closed area. With the structure provided, the chimney effect of the present invention is not lost,
High heat dissipation effect can be maintained. Thereby, work such as attaching the screw 11 to the inside through the work hole 25 can be performed so that the screw does not protrude from the rear surface.

[Brief description of the drawings]

FIG. 1 is a rear perspective view of an electronic refrigerator according to an embodiment of the present invention.

FIG. 2 is a schematic diagram of a heat radiation path of a conventional electronic refrigerator.

FIG. 3 is a schematic diagram of a heat radiation path of the electronic refrigerator of the present invention.

FIG. 4 is a rear perspective view of a conventional electronic refrigerator.

FIG. 5 is a rear perspective view of an electronic refrigerator according to another embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Electronic refrigerator, 2 ... Insulated box, 3 ... Outer box, 4 ... Insulation material, 5 ... Hole, 6 ... Heat absorption plate, 7 ... Peltier element, 8 ...
Radiator plate, 9 radiator fin, 10 cooling system, 11…
Screws, 12 tools, 20 back plate, 21, 22, 23,
24: heat dissipation hole, 25: working hole.

Claims (2)

[Claims] 1. A heat insulating box, a cooling system attached to a rear side of the heat insulating box, and a back plate covering a rear surface of the heat insulating box to prevent contact of the cooling system with a high-temperature portion. An electronic refrigerator of a natural convection type heat radiator having a structure in which heat radiating holes of the rear plate are concentrated at upper and lower ends of the rear plate and a middle portion thereof is closed. 2. The method according to claim 1, further comprising a hole in the middle of the back plate, the number of holes being small enough to prevent human fingers from entering and not more than 10% of the area covered so as not to hinder the chimney effect. The electronic refrigerator according to claim 1.