JPH033153B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a so-called direct cooling type refrigerator in which the wall surface of the freezing chamber is constituted by a cooler. Regarding the refrigerator that looks like this.

[Technical background of the invention]

Recently, in so-called direct cooling type refrigerators in which the wall surface of the freezer compartment is constructed of a box-shaped freezer cooler, the lower wall is constructed of the first cooler, and the upper wall has almost no contact with stored items. The wall is configured with a second cooler set to exhibit a lower cooling temperature than the first cooler, so that frost formation is concentrated on the second cooler, and as a result, defrosting is also performed. This second cooler can be used in one place to prevent the heat of the defrosting heater and the defrosting water from having an adverse effect on the stored items as much as possible. A defrosting heater coated with a heat-fusible film is installed on the back surface of the second cooler, which has evaporation pipes arranged in a meandering manner on the back surface of the cooling sheet. It was placed between the pipes and bonded by thermocompression bonding.

[Problems with background technology]

By the way, in general, in a cooler, since a low-temperature refrigerant exists in the evaporation pipe, the rate of defrost in the evaporation pipe in the cooler tends to be delayed during defrosting. Since the defrost heater is placed between the evaporation pipes,
The frost on the inner surface of the second cooler melts well in the area along the defrosting heater, but it does not melt easily in the area along the evaporation pipe, leaving the defrosting area mottled, making it easy for defrost water to fall. As the temperature rises, the area that has been defrosted first may start to heat up, which may have a negative effect on the stored items.Furthermore, it takes a long time to defrost the entire area. The outside is usually filled with a heat insulating material, but there is a risk that the heat insulating material may get into the area around the defrost heater located on the back of the second cooler, and the transmission between the defrost heater and the second cooler is affected. There is also a problem that thermal properties are impaired, and
Generally, a hydrophilic treatment layer is formed on the inner surface of the second cooler to prevent defrost water from falling. However, when attaching the defrost heater to the second cooler, it is necessary to attach it by thermocompression bonding as described above. Therefore, there was a risk that the hydrophilic treatment layer on the inner surface of the second cooler would melt due to the heat.

[Purpose of the invention]

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a refrigerator that can defrost the entire body uniformly and improve heat transfer from the defrost heater to the second cooler. It is on offer.

[Summary of the invention]

In the present invention, the lower wall of the freezer compartment is constituted by a first cooler, and the upper wall is constituted by a second cooler having evaporation pipes arranged in a meandering manner on the back side of a cooling sheet. The second cooler is set to have a lower cooling temperature than the first cooler, and a heat transfer sheet having linear defrost heaters attached in a meandering manner is attached to the second cooler. It is characterized in that the evaporation pipe line is covered on the back side of the cooling sheet of the container, and the defrosting heater is installed so as to intersect with the evaporation pipe line.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. First, Fig. 1 shows the upper part of the refrigerator. In the same figure, 1 is the refrigerator main body, and this is a heat insulating material between the outer box 2 and the freezer compartment cooler 3 and inner box 4 housed therein. A freezer compartment 6 is formed by the freezer compartment cooler 3, and a refrigerator compartment 8 is formed inside the inner box 4, which is cooled by a refrigerator cooler 7. There is. Now, the details of the freezer compartment cooler 3 will be explained with reference to FIG. 1 and FIG. The evaporation pipe 10 is arranged in a meandering manner on the lower surface of the sheet 9a, for example, in a pipe-on-sheet manner. Reference numeral 11 denotes a second cooler, which forms the upper wall and back wall of the freezing compartment 6, and has an evaporation pipe line 13 arranged in a meandering manner on the back side of the cooling sheet 12, also in a pipe-on-sheet method. It consists of The ceiling surface of the cooling sheet 12 of the second cooler 11 is gently sloped downward to the rear, and the back surface hangs down from the rear edge of the ceiling surface. It is formed in a V shape. Reference numeral 14 denotes a linear defrosting heater, which is pasted in advance on a heat transfer sheet 15 made of aluminum foil (on the inner side in FIG. 2) in a meandering manner. And this heat transfer sheet 15
The evaporation pipe line 13 is covered with the back surface of the cooling sheet 12 in the second cooler 11, and the defrosting heater 14 intersects with the evaporation pipe line 13, and is fixed with tape or glued with an adhesive. It is installed by Here, the meandering pitch P of the defrosting heater 14 is
It is set to 10mm or less. Note that the second cooler 11
A hydrophilic treatment layer is formed on the inner surface by applying a hydrophilic coating. Reference numeral 16 denotes a plastic gutter member, and a drain port 17 is formed approximately in the center of the gutter member. Numerals 18 and 19 are plastic left and right plates forming the left and right walls of the freezer compartment 6, respectively. Therefore, these first coolers 9
The freezer compartment cooler 3 is configured in a box shape by combining the second cooler 11, the gutter member 16, and the left and right side plates 18, 19.
In this case, the second cooler 11 is set to have a cooling temperature lower than that of the first cooler 9 by, for example, 5° C. or more, so that frost is concentrated on the second cooler 11. ing. Here, as shown in FIGS. 1 and 3, the outer surface of the freezer compartment cooler 3 is filled with the above-mentioned heat insulating material 5.
When filling the second cooler 11 , the defrosting heater 14 is pressed by the heat insulating material 5 through the heat transfer sheet 15 .
closely followed. In this case, since the defrosting heater 14 is covered with the heat transfer sheet 15, the heat insulating material 5 does not enter around the entire circumference of the defrosting heater 14.

The refrigeration cycle configuration including the first cooler 9 and the second cooler 11 will be described based on FIG. The outlet 23b of the differential pressure valve 23 is connected to the inlet 25a of the solenoid valve 25 via the capillary tube 24.
and one outlet 25b of this solenoid valve 25.
to the intake port 2 of the compressor 20 via the refrigerator compartment cooler 7, the second cooler 11, and the check valve 26 in this order.
Connected to 0b. Also. The other outlet 25c of the solenoid valve 25 is connected to the inlet 28a of the bubble pump 28 via the capillary tube 27, and the one outlet 28b of the bubble pump 28 is connected to the second cooling via the capillary tube 29. The other outlet 28c is connected to the inlet side of the second cooler 11 via the capillary tube 30 and the first cooler 9, and
The other inlet 23c of the differential pressure valve 23 is connected between the inlet 20b of the compressor 20 and the check valve 26. Note that 31 is a thermosahoin for heat radiation of the compressor 20. In this refrigeration cycle, by controlling the electromagnetic valve 25 and the bubble pump 28, etc., three types of refrigerant flow forms are obtained in the basic body as shown by arrows A, B, and C. In the case of the distribution form shown in FIG.
In the case of the distribution form shown by arrow C, only the freezer compartment 6 is cooled by the second cooler 11, and in the case of the circulation form shown by arrow C, the first cooler 9 and the second cooler 11 are cooled. As a result, only the freezer compartment 6 is rapidly cooled.

Now, in the refrigerator configured as described above, when defrosting heater 14 is energized and generates heat, when defrosting, that is, defrosting the frost concentrated on the inner surface of second cooler 11, is performed, this second Cooler 11
Because the evaporation pipe line 13 and the defrosting heater 14 intersect with each other, the portion of the evaporation line 13 where frost is originally difficult to thaw is thawed at the same time as other parts, and in this case, the heat transfer sheet At step 15, the heat of the defrosting heater 14 is transferred to the entire surface of the second cooler 11, so that the entire surface of the second cooler 11 is uniformly defrosted. The defrosted water is then transferred to the second cooler 11.
The water flows backward along the slope of the ceiling surface, flows down the back surface along with the defrosted water generated on the back surface, and is guided to the drain port 17 of the gutter member 16.

According to this embodiment as described above, the second cooler 1
Since the evaporation pipe line 13 and the defrosting heater 14 are arranged to intersect with each other, it is possible to defrost the part of the evaporation pipe line 13, which is normally difficult to defrost, at the same time as other parts. is attached to the heat transfer sheet 15 and attached to the second cooler 11 together with the heat transfer sheet 15.
The heat can be transferred to the entire surface of the cooler 11, the defrosting will not become mottled as a whole, the defrosting water can be prevented from falling, the defrosting can be carried out in a short time, and there is no partial heating. Furthermore, since the defrosting heater 14 is covered with the heat transfer sheet 15, the heat insulating material 5 does not enter the entire circumference of the defrosting heater 14, and the heat insulating material 5 does not enter the entire circumference of the defrosting heater 14. The material 5 brings the defrost heater 14 into close contact with the second cooler 11 via the heat transfer sheet 15, thereby improving heat transfer from the defrost heater 14 to the second cooler 11. , the defrosting heater 14 can be attached to the second cooler 11 by taping or adhesive bonding without thermocompression bonding, and the second cooler 11
It is possible to eliminate the possibility that the hydrophilic treatment layer on the inner surface of the container will dissolve.

In particular, in this embodiment, since the meandering pitch P of the defrosting heater 14 is set to 10 mm or less, the second cooler 11 can be heated more uniformly and defrosting can be performed more efficiently.

In addition, the present invention is not limited to the embodiments described above and shown in the drawings, and may be implemented with appropriate modifications within the scope of the gist.

〔Effect of the invention〕

As explained above, the present invention can defrost the entire body substantially simultaneously and uniformly, prevent the defrosting water from falling, and eliminate the need for excessive heating of the second cooler.
This can prevent adverse effects on stored items, shorten the defrosting time, and improve thermal efficiency by improving the thermal conductivity of the defrosting heater to the second cooler. Moreover, the defrosting heater can be attached to the second cooler by taping or adhesive bonding instead of heat welding, and if a hydrophilic treatment layer is formed on the inner surface of the second cooler, This has excellent effects such as eliminating the risk of melting.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention,
FIG. 1 is a vertical sectional side view of the upper part of the refrigerator, FIG. 2 is an exploded perspective view of a freezer compartment cooler, FIG. 3 is an enlarged vertical sectional side view of the main parts, and FIG. 4 is a refrigeration cycle configuration diagram. In the figure, 6 is a freezer compartment, 9 is a first cooler, 10 is an evaporation line, 11 is a second cooler, 12 is a cooling sheet, 13 is an evaporation line, 14 is a defrosting heater, and 15 is a transmission line. It is a thermal sheet.

Claims (1)

[Claims] 1. The lower wall of the freezer compartment is constituted by a first cooler, and the upper wall is constituted by a second cooler formed by arranging evaporation pipes in a meandering manner on the back side of a cooling sheet. However, in the case where the second cooler is set to have a lower cooling temperature than the first cooler,
A heat transfer sheet to which a linear defrosting heater is attached in a meandering manner is placed on the back side of the cooling sheet of the second cooler to cover the evaporation pipe line, and the defrost heater intersects with the evaporation pipe line. A refrigerator characterized by being attached to. 2. The refrigerator according to claim 1, wherein the meandering pitch of the defrosting heater is set to 10 mm or less.