JPS621194B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a refrigerator equipped with a freezer compartment, and more particularly to a refrigerator in which frost formation in the freezer compartment is concentrated in one place.

Recently, refrigerators equipped with a freezer compartment have become popular.
Among such refrigerators, in particular, so-called direct cooling type refrigerators, in which the cooler is formed into a substantially rectangular box shape and the inside thereof is used as a freezing chamber, generally The interior surface of the room is cooled almost uniformly over almost the entire area.

However, in the case configured as described above, frost forms on almost the entire inner surface of the freezer compartment during operation, and not only does the refrigeration efficiency decrease due to the adiabatic effect of this frost, but also the There were also problems such as frost formation on the surface.

Therefore, in order to solve this problem, we have recently developed a partition wall that divides the freezer compartment into a frozen storage area and a non-accommodation area, an air flow path that communicates the frozen storage area and the non-accommodation area, and a a first cooler that cools the frozen object by contacting the frozen object housed in the storage section; a second cooler that is provided in the non-accommodated section and is maintained at a lower temperature than the first cooler; Refrigerators have appeared that are equipped with a fan that forcibly circulates air in a frozen object storage section and air in a non-accommodation section through the air flow path. In other words, this refrigerator
By making the temperature of the second cooler sufficiently lower than that of the first cooler, the frost adhering to the surface of the first cooler and the surface of the frozen object is sublimated and vaporized, and this steam is With the help of a fan, the frost is guided to the surface of a second cooler disposed in the non-accommodating part, and is deposited as frost on this surface. Therefore, in the refrigerator configured in this manner, it is possible to prevent thick frost from adhering to the wall surface of the frozen object storage section or the surface of the frozen object, and thus it is possible to prevent a decrease in refrigeration efficiency.

However, even with the refrigerator configured as described above, the following problems occurred. That is,
In order to remove the frost adhering to the surface of the second cooler, when the fan operation is stopped and the surface of the second cooler is heated with a heater, the frost on the surface of the second cooler is melted and the second cooler is not housed. The temperature inside the room increases and the humidity also increases. At this time, since the inside of the frozen object accommodating section is still in a low temperature state, the temperature difference between the frozen object accommodating section and the non-accommodating section causes convection through the air flow path described above. The air flowing from the non-accommodating section into the frozen material accommodating section has high humidity as described above. When humid air flows into the low-temperature frozen storage area, ice buildup occurs on the boundary between the non-accommodating area and the frozen storage area and on the walls of the frozen storage area, eventually resulting in complete ice formation. There were problems in that defrosting could not be carried out and cooling performance was inhibited by the ice layer.

The present invention was made in view of the above circumstances, and its purpose is to efficiently concentrate frost in one place without adversely affecting other parts of the freezing room, and to improve refrigeration efficiency. To provide a refrigerator equipped with a freezing compartment which can be further improved, can completely accomplish defrosting within a short time, and can improve cooling performance during defrosting.

The invention will now be explained by detailed illustrated embodiments.

FIG. 1 is a longitudinally cut view of a refrigerator according to the present invention.

In the figure, 1 in the figure is the refrigerator main body,
This refrigerator main body 1 includes a casing 2 with one side open and a vertically long insulation function, and a casing 2 that has a heat insulation function.
and a heat insulating door body 3 that can be opened and closed to selectively close the open surface of the door body. A partition wall 4 having a heat insulating function is provided inside the refrigerator main body 1 to partition the inside into two vertically. 5
In addition, the room formed on the upper side is used as a freezing chamber 6. The door body 3 includes a lower door 7 that selectively closes one side of the refrigerator compartment 5 and an upper door 8 that selectively closes one side of the freezer compartment 6.

In the refrigerator compartment 5, there are a plurality of shelves 9 on which stored items such as food are placed, and a cooler (=evaporator) 10 is arranged in an inclined state near the inner surface of the upper wall thereof. It is provided. A condensation tray 11 is provided on the lower side of the cooler 10 to cover this lower portion, and the water droplets collected on this tray 11 are transferred to a pipe 12 provided through the wall of the housing 2. The liquid is guided into a pipe 13 provided along the outer surface of the casing 2 through the pipe 13, and flows down the pipe 13. Note that the water droplets flowing down inside the pipe 13 are guided into an evaporation tray 14 provided below the housing 2, and evaporate from this tray 14 into the atmosphere.

On the other hand, a first cooler (first evaporator) 15 is attached to the upper, lower, and side walls of the wall forming the freezer compartment 6 so as to be in close contact with these walls.
In addition, a partition wall 16 is provided in the freezer compartment 6 to divide the interior of the freezer compartment 6 into front and back sections when viewed from the door side, and the space on the door side divided by the partition wall 16 is used for food storage. The space on the opposite side is defined as a non-accommodating area 18. Note that the volume of the non-accommodating part 18 is several tenths of that of the accommodating part 17.
is set to . Inside the non-accommodating portion 18, there is a second wall spaced apart from the wall forming the non-accommodating portion 18.
A cooler (second evaporator) 19 is provided in an inclined state. The second cooler 19 is formed by meandering a pipe, and a sheathed heater 21 is attached along the pipe 20, as shown in FIG. Further, on the lower side of the second cooler 19, a dew pan 22 is provided to wrap around this lower position.
The water droplets collected on the dew pan 22 are guided to the pipe 13 through a pipe 23 provided through the wall of the housing 2.

The upper and lower parts of the partition wall 16 are provided with storage portions 1.
7 and the non-accommodating part 18, an air flow path 24,
25, and a damper device 26 for selectively closing the flow path 24 is provided near the flow path 24. The damper device 26 is specifically constructed as shown in FIG. That is, freezer compartment 1
A damper plate 28 made of a magnetic material is suspended from the inner surface of the upper wall of 7 via a flexible member 27 to a position reaching below the lower end of the flow path 24, and an iron core 29 is placed opposite the damper plate 28. A coil 30 is attached to this iron core. Also,
In the non-accommodating part 18 and in the vicinity of the damper device 26, air in the non-accommodating part 18 and the accommodating part 17 are
A fan 31 is provided for forcibly circulating the air inside through the channels 24 and 25.
In addition, in FIG. 1, 32 indicates a condenser attached to the back of the housing 2, and 33 indicates a compressor.

The compressor 33, condenser 32, first and second coolers 15, 19, and cooler 10 are connected as shown in FIG. 3 to form a refrigeration circuit. That is, Freon is used as a refrigerant, this Freon is compressed by a compressor 33, and the compressed Freon is transferred from a condenser 32 to a first capillary tube 34 to a cooler 10 to a first cooler 15 to a second cooler.
It flows through the route from the capillary tube 35 to the second cooler 19, and is compressed again by the compressor 33. Then, the operation of the compressor 33, the sheathed heater 21, and the coil 3 of the damper device 26 are performed.
0. The fan 31 is energized by the following control circuit. That is, as shown in FIG. 3, a temperature detector 41 such as a thermistor is provided in the refrigerator compartment 5 cooled by the cooler 10, and the temperature inside the refrigerator compartment 5 is determined based on the output of this temperature detector 41. When the temperature of the compressor 33 is higher than a predetermined value, the motor control circuit 42 is activated to operate the compressor 33. Further, a frost amount detector 43 such as a thermistor is provided near the second cooler 19, and a switch circuit 44 is activated based on the output of this detector 43 when the amount of frost exceeds a predetermined value. Then, the sheathed heater 21 and the coil 30 are energized for a certain period of time, and the driving of the fan 31 is stopped only during the above period.

Next, the operation of the refrigerator of the present invention constructed as described above will be explained.

First, when the power is turned on, the temperature inside the refrigerator compartment 5 is high at this point, so the motor control circuit 4 immediately
2 operates, and as a result, the compressor 33 starts operating. Further, the fan 31 also starts rotating, and as a result, the air in the freezer compartment 6 is transferred from the storage section 17 to the flow path 2.
4 to the non-accommodating part 18 to the channel 25 to the accommodating part 17. When the compressor 33 is in operation, Freon, which is a refrigerant, such as Freon R-
12 is pressurized to, for example, about 10 kg/cm ² by the compressor 33, and then flows into the condenser 32, where it is liquefied. Liquefied Freon R-12
is reduced in pressure to, for example, about 1.2 kg/cm ² by the first capillary tube 34 and flows into the cooler 10 and the first cooler 15.
The heat in the refrigerator compartment 5 and the freezer compartment 6 is taken away through 0 and 15 to evaporate. Note that the surface temperature of each cooler 10, 15 at this time is, for example, about -25°C. Moreover, the cooling area of each cooler 10, 15 is set in advance so that the temperature in the refrigerator compartment 5 is about +3°C and the temperature in the freezer compartment 6 is about -20°C by this cooling. There is.

The remaining liquefied Freon R-12 that has passed through the first cooler 15 is further reduced in pressure to about 1.0 kg/cm ² in the second capillary tube 35 and flows into the second cooler 19. do. Since Freon has the property of evaporating at a lower temperature as the pressure is lower, the liquefied Freon R-12 flowing into the second cooler 19
is also evaporated here, and as a result, the second cooler 1
The surface temperature of the cooling device 9 is lower than that of the first cooler 15, for example, about -30°C. The refrigerant that has passed through the second cooler 19 is then returned to the compressor 33 and repeats the above-described series of cycles.

By the way, when operated in the above-described cycle, the inside of the refrigerator compartment 5 and the inside of the freezer compartment 6 are gradually cooled. In this case, when the temperature inside the freezer compartment 6 becomes 0° C. or lower, frost will adhere to the inner walls and the surfaces of the stored items. However, as mentioned above, since the surface temperature of the second cooler 19 is set to be lower than the surface temperature of the first cooler 15, frost that adheres to the inner wall and the surface of the stored items gradually sublimates and vaporizes, and this vapor moves from the flow path 24 to the non-accommodating part 18 by forced convection based on the action of the fan 31, and adheres as frost on the surface of the second cooler 19. . In this case, as mentioned above, forced convection is caused in the freezer compartment 6 by the fan 31, so this convection promotes sublimation of the frost adhering to the surfaces of the stored items, etc., and these frosts are quickly removed. 2. Then, it moves to the surface of the second cooler 19. Therefore, in a steady state, only the surface of the second cooler 19 is where frost forms in the freezer compartment 6 .

When the amount of frost on the surface of the second cooler 19 gradually increases and exceeds a predetermined value, the switch circuit 44 is activated by the output of the frost amount detector 43.
The sheathed heater 21 and the coil 30 are energized for a certain period of time, and the drive of the fan 31 is stopped for this period. When the sheathed heater 21 is energized, the second cooler 19 is heated, and this heating melts the frost adhering to the surface, which becomes water droplets and falls onto the dew pan 22. In other words, defrosting is performed. and,
The water collected in the dew pan 22 is discharged to the outside via a pipe 23. On the other hand, when the coil 30 is energized, the damper plate 28 is attracted to the iron core 29 as shown in FIG. Therefore, even if the humidity inside the non-accommodating part 18 increases due to the energization of the sheathed heater 21, this highly humid air flows into the accommodating part 17.
As a result, the storage part 1 can be stopped immediately.
Defrosting is carried out in a state where no icing occurs on the walls, etc. of 7. Then, after a certain period of time has passed, the energization of the sheathed heater 21 and the coil 30 is released, and the second
The cooler 19 is cooled to a lower temperature than the first cooler 15, and the operation of the fan 31 is restarted. Note that the compressor 33 is operated while the temperature inside the refrigerator compartment 5 is higher than a predetermined value.

In this way, the inside of the freezer compartment 6 is partitioned into the storage section 17 that directly stores frozen items such as food, and the non-accommodation section 18 that communicates with this, and the non-accommodation section 18 is cooled to a lower temperature than the other portions. A second cooler 19 is disposed to concentrate frost on the second cooler 19, and a damper device 26 and a fan 31 are provided in an air flow path that communicates the accommodation section 17 and the non-accommodation section 18. During the period when the second cooler 19 is heated to remove the deposited frost, the damper device 26 is closed and the fan 31 is stopped.

Therefore, during steady operation, the first cooler 15 directly cools the contents stored in the storage section 17.
The second cooler 1 quickly removes frost generated on the surface of the stored items due to the temperature difference between
9, thereby shortening the time required for freezing. In addition, when defrosting, the damper device 31 is closed, and the fan 26
Since the non-accommodating portion 18
It is possible to reliably prevent the occurrence of icing on the walls of the accommodating section 17 due to the high humidity air flowing into the accommodating section 17, and as a result, the cooling performance during the defrosting period, which is likely to occur when icing occurs, is improved. It is possible to prevent a decrease in refrigeration efficiency and a decrease in refrigeration efficiency upon restart.

As described above, according to the present invention, it is possible to provide a refrigerator that is easier to use, has improved refrigeration efficiency, and can reliably prevent the defrosting operation from having an adverse effect on cooling performance.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a refrigerator according to an embodiment of the present invention, FIG. 2 is a perspective view showing a part of the second cooler in the same embodiment, and FIG. 3 is a refrigeration circuit in the same embodiment. FIG. 4a is a diagram illustrating the configuration of the damper device in the same embodiment, and FIG. 4b is a diagram illustrating the operation of the damper device. 1 ... Refrigerator body, 5... Refrigerator compartment, 6... Freezer compartment, 10... Cooler, 15... First cooler, 1
6... Partition wall, 17... Housing section, 18... Non-accommodating section, 19... Second cooler, 24, 25... Air flow path, 31... Fan.

Claims (1)

[Claims] 1. A refrigerator main body, an air flow path formed in the refrigerator main body that communicates a frozen product accommodating part and a non-accommodating part, a damper device that selectively closes this air flow path, and a damper device accommodated in the frozen product accommodating part. A first cooler that directly cools the frozen object, a second cooler provided in the non-accommodating part, and a refrigerant flowing between the second cooler and the first cooler. a refrigeration circuit that allows the air to flow and maintains the temperature of the second cooler at a lower temperature than the temperature of the first cooler; a fan for forced circulation through the second cooler; means for heating and removing frost adhering to the second cooler; and means for closing the damper device and stopping the fan when the means is in operation. A refrigerator characterized by: