JP2003279228A - Refrigerator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To quickly and efficiently perform defrosting operation for a condenser by a defrosting heater. <P>SOLUTION: This refrigerator includes a storage chamber 7 such as a freezer or a refrigerating chamber, and a condenser chamber 9 having a blowing fan 10, a condenser 11 and the defrosting heater 16, in which the air cooled by the condenser 11 is circulated and supplied to the storage chamber 7 by the operation of the blowing fan 10. During the defrosting operation for the condenser 11 by the defrosting heater 16, the blowing fan 10 is rotated in the reverse direction, and the air heated by the defrosting heater 16 is circulated and supplied to the condenser 11 in the condenser chamber 9. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a storage room such as a freezing room or a refrigerating room, a blower fan, a cooler and a defrost heater, and the air cooled by the cooler is the blower fan. The present invention relates to a refrigerator such as a home refrigerator or a commercial refrigerator, which is provided with a cooler chamber that is circulated and supplied to the storage chamber by the operation of, and in particular, a flammable refrigerant is filled in a refrigerant circuit including the cooler. It is about the refrigerator.

[0002]

2. Description of the Related Art In a refrigerator of this type, when frost is formed on the cooler, the defrost heater heats the cooler to perform a defrost operation. However, heat transfer from the defrost heater to the cooler is performed. Since the method is performed by heat conduction or heat radiation, it takes a long time to heat the entire cooler, and there is a drawback that the defrosting time becomes long.

Further, as a refrigerant to be filled in the refrigerant circuit of a refrigerator, an alternative refrigerant such as an HC (hydrocarbon) refrigerant has come to be used instead of a CFC refrigerant which has an adverse effect on the global environment such as ozone layer depletion. It was However, H
Flammable refrigerants such as C refrigerant have a problem of ignition due to an ignition source, and it is necessary to give sufficient consideration to refrigerant leakage.

Particularly, in the case where an electric defrosting heater is arranged near the cooler and defrosting is performed by energizing the defrosting heater when frost is formed on the cooler, the surface temperature of the defrosting heater is combustible. If the refrigerant leaks from the cooler, the flammable refrigerant may be ignited because the temperature exceeds the ignition temperature.

[0005]

Therefore, the present invention has a storage room such as a freezing room or a refrigerating room, a blower fan, a cooler, and a defrost heater, and the air cooled by the cooler is provided. In a refrigerator including a cooler chamber that is circulated and supplied to the storage chamber by operating the blower fan, a defrosting operation of the cooler by the defrosting heater can be performed quickly and efficiently, and further, A flammable refrigerant is used in a refrigerant circuit including the cooler, and an object is to prevent the flammable refrigerant from igniting even when the defrost heater is energized under a condition where there is refrigerant leakage from the cooler. .

[0006]

Therefore, in the first invention, a storage room such as a freezing room or a refrigerating room, a blower fan,
A refrigerator having a cooler and a defrost heater, and a cooler chamber in which air cooled by the cooler is circulated and supplied to the storage chamber by operation of the blower fan,
During the defrosting operation of the cooler by the defrost heater, the blower fan is reversely rotated so that the air heated by the defrost heater is circulated and supplied to the cooler in the cooler chamber. And

According to the second aspect of the invention, there is provided a storage room such as a freezing room or a refrigerating room, a blower fan, a cooler and a defrost heater, and the air cooled by the cooler is the blower fan. In a refrigerator provided with a cooler chamber that is circulated and supplied to the storage chamber by the operation of, when the defrosting operation of the cooler by the defrost heater is performed, the blower fan is reversely rotated and heated by the defrost heater. Air is circulated and supplied to the cooler in the cooler chamber, and a damper device blocks the flow of air between the cooler chamber and the storage chamber.

Further, in the third invention, in the refrigerator of the first or second invention, a bypass passage for guiding the air heated by the defrost heater to the cooler is formed in the cooler chamber. It is characterized by

The fourth invention is characterized in that in the refrigerator of the first to third inventions, a reflector is provided between the cooler and the defrost heater.

The fifth aspect of the invention is characterized in that, in the refrigerator of the fourth aspect, the defrost heater and the reflection plate are in thermal contact with each other via a heat conducting member.

The sixth invention is characterized in that, in the refrigerator of the first to fifth inventions, the refrigerant circuit including the cooler is filled with a combustible refrigerant.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 1 denotes a refrigerator main body in which a foam insulating material 4 is filled between an inner box 2 and an outer box 3, the inside of which is divided into upper and lower parts by a partition wall 5, a freezer compartment,
Storage rooms 6 and 7 such as a refrigerating room are formed.

A cooler chamber 9 partitioned by a partition wall 8 is provided behind the storage chamber 7, and the cooler chamber 9 includes a blower fan 10 and a finned cooling pipe. 11 and 11 are provided above and below.

An outlet 12 is provided above the partition wall 8 facing the blower fan 10, and a suction port 13 is provided below the partition wall 8. When the blower fan 10 is operated, a cooler 11 is provided. The cool air cooled in (3) is supplied to the storage chamber 7 from the air outlet 12 and the air in the storage chamber 7 returns from the suction port 13 into the cooler chamber 9. The cold air in the cooler chamber 9 is also circulated and supplied to the storage chamber 6 by a cold air distribution mechanism (not shown).

The outlet 12 is opened during the cooling operation, and is opened during the defrosting operation.
A damper device D for closing the valve is provided. Further, the cooler chamber 9 has an air passage for bypass (bypass passage).
A duct wall W forming P is provided.

The cooler 11 is annularly connected to a compressor, a condenser, and a pressure reducing mechanism (not shown) to form a refrigerant circuit. In the refrigerant circuit, flammable HC refrigerant such as isobutane or propane is provided. Is enclosed.

As shown in FIGS. 2 to 4, the cooler 11 comprises side plates 11A arranged at both ends, a large number of cooling fins 11B, and a cooling tube 11C. The side plates 11A at both ends and every other cooling fin 11B have a downwardly extending portion, and there is an inverted U-shaped cutout 1 there.
4 are provided.

A reflecting plate 15 having an inverted U-shaped cross section is caulked and coupled to these notches 14 and is installed in a thermal contact state. The reflection plate 15 is made of a metal plate having good heat conductivity, and also has a function as a heat radiation plate. Further, the lower end of the reflection plate 15 is made to project downward from the lower end of the cooler 11. In this embodiment, both side plates 11A
And the cooling fins 11B are projected below the downward extending portions.

An electric defrost heater 16 for melting the frost of the cooler 11 is attached to the inside of the reflector 15. As the defrosting heater 16, an electric heater such as a glass tube heater or an aluminum tube heater is used. Also,
The refrigerator main body 1 below the defrost heater 16 includes a cooler 11
The dew tray 17 for receiving the drain water and the ice dropped from is integrally formed, and the drain water of the dew tray 17 is discharged to the outside.

For example, in the case of a glass tube heater, the defrosting heater 16 is phase-controlled so that the surface temperature of the glass tube is maintained at a low temperature lower than the ignition temperature of the flammable refrigerant and a predetermined temperature or less when energized. The temperature is controlled by means or the like. That is, if the flammable refrigerant is isobutane, which is an HC refrigerant, its ignition temperature is 493 degrees C. Therefore, the surface temperature of the glass tube is controlled to be 394 degrees C or less, which is 100 degrees C or more lower than that. It

In the above structure, the air in the cooler chamber 9 cooled by the cooler 11 is supplied from the outlet 12 to the storage chamber 7 by the operation of the blower fan 10, and the suction port 13
Return to the cooler room 9. Further, since the air in the cooler chamber 9 is circulated and supplied to the storage chamber 6 by a cool air distribution mechanism (not shown), the storage chamber 6 is maintained in the freezing temperature zone (around -20 ° C) and the storage chamber 7 is kept in the refrigeration temperature zone. It is maintained (around 3 degrees C).

When frost adheres to the cooler 11, the damper device D closes the outlet 12 and the blower fan 10 is rotated in the reverse direction to energize the defrost heater 16. When the defrost heater 16 generates heat, the heat of the defrost heater 16 is reflected by the reflection plate 15, and the air below the reflection plate 15 is heated. Then, this air becomes warm air as shown by the broken line, passes through the bypass passage P, and is circulated and supplied to the cooler 11.

Further, since the reflection plate 15 is installed in thermal contact with the side plate 11A and the cooling fins 11B, there is heat conduction from the reflection plate 11 to the cooling fins 11B, and moreover,
Since there is also heat radiation from the reflection plate, the frost adhering to the cooling fins 11B is melted, and a part thereof becomes ice pieces and falls.

The ice pieces and drain water are guided downward along the outer periphery of the reflection plate 15, accumulated in the dew tray 17 and discharged to the outside of the refrigerator body 1. At this time, the ice pieces accumulated in the dew pan 17 are also melted by the hot air and the heat reflection from the reflection plate 15, so that the dew pan 17 does not have to be clogged.

Thus, during the defrosting operation, the air heated by the defrosting heater 16 becomes warm air and the cooler 11
The heat of the defrosting heater 16 is transferred to the cooler 11 via the reflection plate 11 by heat conduction and heat radiation, so that the defrosting of the cooler 11 is performed quickly and efficiently. In addition to the case where the cooler 11 is directly heated by the defrost heater 16, the risk of ignition is reduced even if the flammable refrigerant leaks from the cooling tube 11C.

Moreover, since the surface temperature of the defrosting heater 16 is maintained at a temperature lower than the ignition temperature of the flammable refrigerant by a predetermined temperature (for example, 100 ° C.) or more, even if a large amount of the flammable refrigerant is ejected, There is no need to worry that the frost heater will be the ignition source.

The reflecting plate 15 has an inverted U-shaped cross section, and is located at the bottom of the cooler 11 and at the lower end thereof.
Since it projects downward below 1, the entire cooler 11 can be efficiently heated by the radiant heat of the reflection plate 15, and the air under the cooler 11 is heated by the heat reflection of the reflection plate 15 and the dew tray The defrosting operation can be appropriately performed while maintaining the safety of the refrigerator using the flammable refrigerant, such as the fact that the ice pieces accumulated in 17 can be melted.

5 to 8 show another embodiment of the present invention. In this embodiment, the reflector 15
The inside of is fitted into the defrosting heater 16, and the upper part is partitioned into a plurality of rooms by a plurality of heat conducting fins (heat conducting members) 18 matching the cross-sectional shape of the reflection plate 15.

The heat-conducting fins 18 are made of a circular metal plate having good heat conductivity, and the defrosting heater 16 and the reflecting plate 1 are provided.
They are in thermal contact with each other by being caulked.

Therefore, in this structure, the air in the room partitioned by the heat conduction fins 18 inside the reflection plate 16 becomes warm air and is circulated and supplied to the cooler 11, and at the same time, the defrost heater 16 causes the reflection plate to flow. The heat conduction to 15 is also good, and the defrosting operation can be performed more efficiently.

Although the embodiments of the present invention have been described above, various alternatives, modifications, and variations can be made by those skilled in the art based on the above description, and the present invention includes the above-described various modifications without departing from the spirit thereof. It is intended to cover alternatives, modifications or variations.

[0032]

As described above, the present invention has a storage room such as a freezing room or a refrigerating room, a blower fan, a cooler and a defrost heater, and the air cooled by the cooler is In a refrigerator including a cooler chamber that is circulated and supplied to the storage chamber by operating a blower fan, the blower fan is rotated in reverse during defrosting operation of the cooler by the defrost heater, and is heated by the defrost heater. Since the generated air is circulated and supplied to the cooler in the cooler chamber,
During the defrosting operation, the air heated by the defrosting heater becomes hot air and is circulated and supplied to the cooler, and the entire cooler is heated by hot air to quickly defrost the cooler.
And it can be performed efficiently.

Further, during the defrosting operation of the cooler by the defrosting heater, the damper device cuts off the air flow between the cooler chamber and the storage chamber, so that hot air is stored during the defrosting operation. There is no risk of leaking into the room and adversely affecting food, etc. Furthermore, since a bypass passage for guiding the air heated by the defrost heater to the cooler room is formed in the cooler room, warm air circulation to the cooler is possible. The defrosting operation can be performed more efficiently.

In the case where a reflector is provided between the cooler and the defrost heater, the reflector is used to heat the air to promote warm air circulation and to melt the ice accumulated in the dew tray. Further, in the case where the defrosting heater and the reflecting plate are in thermal contact with each other via the heat conducting member, heat transfer from the reflecting plate to the cooler enables the defrosting operation to be performed more quickly and efficiently. It can be carried out.

As described above, the defrosting of the cooler is performed by circulating the warm air, and further, the reflecting plate is provided between the cooler and the defrost heater so that the defrost heater indirectly heats the cooler. Since it is performed, if the flammable refrigerant is used in the refrigerant circuit including the cooler, even if the defrost heater is energized under the condition that the refrigerant leaks from the cooler, the flammable refrigerant does not ignite. Therefore, the safety of the refrigerator using the flammable refrigerant can be maintained.

[Brief description of drawings]

FIG. 1 is a sectional view showing a schematic structure of a refrigerator according to an embodiment of the present invention.

FIG. 2 is a perspective view of an essential part of the refrigerator of the refrigerator.

FIG. 3 is also a front view of the cooler.

FIG. 4 is a side view of the same cooler.

FIG. 5 is a sectional view showing a schematic structure of a refrigerator according to another embodiment of the present invention.

FIG. 6 is a perspective view of an essential part of the refrigerator of the refrigerator.

FIG. 7 is likewise a front view of the cooler.

FIG. 8 is a side view of the same cooler.

[Explanation of symbols]

1 Refrigerator body 6, 7 storage room 9 Cooler room 10 Blower fan 11 cooler 15 Reflector 16 Defrost heater D damper device P bypass passage

Claims (6)

[Claims] 1. A storage room, such as a freezer compartment or a refrigerating room, and a blower fan, a cooler, and a defrost heater, and the air cooled by the cooler is operated by the blower fan to operate the storage room. In a refrigerator having a cooler chamber that is circulated and supplied to the cooler chamber, the blower fan is rotated in reverse during defrosting operation of the cooler by the defrost heater, and the air heated by the defrost heater is in the cooler chamber. A refrigerator characterized in that it is circulated and supplied to the cooler. 2. A storage room such as a freezing room or a refrigerating room, and a blower fan, a cooler, and a defrost heater, and the air cooled by the cooler is operated by the blower fan to cause the storage room to operate. In a refrigerator having a cooler chamber that is circulated and supplied to the cooler chamber, the blower fan is rotated in reverse during defrosting operation of the cooler by the defrost heater, and the air heated by the defrost heater is in the cooler chamber. And a damper device for interrupting the flow of air between the cooler chamber and the storage chamber. 3. The refrigerator according to claim 1, wherein a bypass passage for guiding the air heated by the defrost heater to the cooler is formed in the cooler chamber. 4. The refrigerator according to claim 1, further comprising a reflector provided between the cooler and the defrost heater. 5. The defrost heater and the reflection plate are in thermal contact with each other via a heat conducting member.
Refrigerator described in. 6. The refrigerator according to claim 1, wherein the refrigerant circuit including the cooler is filled with a combustible refrigerant.