JP7583981B2 - refrigerator - Google Patents

Description

This disclosure relates to refrigerators.

Patent document 1 discloses a refrigerator that has an evaporator in each of the freezer and refrigerator compartments, and controls the temperature of the evaporator by the rotation speed of the compressor.

Japanese Patent Application Publication No. 11-173729

This disclosure provides a refrigerator that can improve the efficiency of the refrigeration cycle when cooling the refrigerator compartment and reduce power consumption.

The refrigerator according to the present disclosure includes a refrigerator compartment, a freezer compartment, a refrigerated evaporator, a freezer evaporator, a refrigerated pressure reducing means connected in series with the refrigerated evaporator, a freezer pressure reducing means connected in series with the freezer evaporator, a compressor connected to an outlet pipe of the refrigerated evaporator and an outlet pipe of the freezer evaporator, a radiator connected in series with a discharge pipe of the compressor, a switching valve for switching the flow of refrigerant to the refrigerated evaporator and the freezer evaporator, and a heat storage material in thermal contact with either the inlet pipe or the outlet pipe of the refrigerated evaporator.

The refrigerator disclosed herein can improve the efficiency of the refrigeration cycle when cooling the refrigerator compartment, thereby reducing power consumption.

Cross-sectional view of a refrigerator according to a first embodiment. Refrigeration cycle diagram of a refrigerator in embodiment 1 A timing chart showing the operation of a refrigerator and a change in room temperature in the first embodiment. Cross-section of a conventional refrigerator Diagram of the refrigeration cycle of a conventional refrigerator

(Foundations and other information that form the basis of this disclosure)
2. Description of the Related Art Some conventional refrigerators include an evaporator in each of a freezing compartment and a refrigerating compartment, and the temperature of the evaporator is controlled by the rotation speed of a compressor (see, for example, Patent Document 1).

Figure 4 is a cross-sectional view of the conventional refrigerator described in the above-mentioned Patent Document 1, and Figure 5 is a diagram of the refrigeration cycle of the same refrigerator.

In Figures 4 and 5, a conventional refrigerator 1 is composed of an insulated box 3 with an open front and divided into upper and lower compartments by a partition 2. The area above the partition 2 is a refrigerator compartment 4, in which the interior temperature is maintained at a refrigeration temperature of approximately 4°C, and the area below the partition 2 is a freezer compartment 5, in which the interior temperature is maintained at a freezing temperature of approximately -18°C. The front is closed by insulated doors 6 and 7, which can be opened and closed freely.

On the back of the refrigerator compartment 4 and the freezer compartment 5, there are a compressor 8 whose capacity can be controlled by an inverter power supply (not shown), a condenser 9 as a radiator connected to the discharge pipe 8a of the compressor 8, a three-way valve 10 as a switching valve, a refrigerator capillary 11 as a refrigerator pressure reduction means, a refrigerator evaporator 14 and a freezer evaporator 15 connected to the freezer capillary 12 as a freezer pressure reduction means to form a freezer cycle 13, and a refrigerator fan 16 and a freezer fan 17 that circulate the cold air generated by each evaporator into the refrigerator compartment 4 and the freezer compartment 5, respectively.

Furthermore, inside the refrigerator compartment 4 and the freezer compartment 5, there are a refrigerator compartment sensor 18 and a freezer compartment sensor 19 that measure the temperature inside each storage compartment (refrigerator compartment 4, freezer compartment 5).

In a conventional refrigerator configured as described above, when the cooling operation starts, the compressor 8 starts operating, and the flow of the refrigerant is switched by the three-way valve 10 based on the temperatures detected by the refrigerator compartment sensor 18 and the freezer compartment sensor 19, thereby switching between cooling the refrigerator compartment 4 and the freezer compartment 5.

First, when cooling the freezer compartment 5, the high-temperature, high-pressure gas refrigerant compressed by the compressor 8 is cooled in the condenser 9 to become a low-temperature, high-pressure liquid refrigerant. This liquid refrigerant flows through the freezer capillary 12 via the three-way valve 10, and becomes a low-temperature, low-pressure gas-liquid two-layer refrigerant that flows to the freezer evaporator 15.

The refrigerant that flows into the freezer evaporator 15 evaporates through heat exchange with the air in the freezer compartment 5, generating cold air using the heat of evaporation, which is then sucked back into the compressor 8.

The cold air generated at this time is circulated through the freezer compartment 5 by the freezer fan 17, cooling the freezer compartment 5, and when the freezer compartment sensor 19 drops below a certain temperature, the cooling operation of the freezer compartment 5 ends.

Next, when cooling the refrigerator compartment 4, the high-temperature, high-pressure gas refrigerant compressed by the compressor 8 is cooled in the condenser 9 to become a low-temperature, high-pressure liquid refrigerant. This liquid refrigerant flows through the refrigeration capillary 11 via the three-way valve 10, and becomes a low-temperature, low-pressure gas-liquid two-layer refrigerant that flows to the refrigeration evaporator 14.

The refrigerant that flows into the refrigeration evaporator 14 evaporates through heat exchange with the air in the refrigerator compartment 4, generating cold air using the latent heat of evaporation, which is then sucked back into the compressor 8.

The cold air generated at this time is circulated through the refrigerator compartment 4 by the refrigerator fan 16, cooling the refrigerator compartment 4, and when the refrigerator compartment sensor 18 drops below a certain temperature, the cooling operation of the refrigerator compartment 4 ends.

When cooling the refrigerator compartment 4, the temperature of the refrigerator compartment 4 is in the refrigeration temperature range of approximately 4°C, and since the air temperature exchanging heat with the refrigeration evaporator 14 is higher than when cooling the freezer compartment 5, the temperature of the refrigeration evaporator 14 is also higher than when the freezer compartment 23 is in cooling mode. As a result, the compression ratio, which is the pressure ratio of the intake gas and discharge gas of the compressor 8, becomes smaller, and the efficiency of the refrigeration cycle 13, which is expressed as the ratio of the input of the compressor 8 to the capacity of the refrigeration evaporator 14, also increases.

On the other hand, as the temperature of the refrigerated evaporator 14 rises, the density of the refrigerant gas sucked into the compressor 8 becomes approximately twice as high as when cooling the freezer compartment 5. This increases the amount of refrigerant circulating through the refrigeration cycle 13, and the capacity of the refrigerated evaporator 14 becomes greater than the load on the refrigerated compartment 4. If the capacity is not fully utilized, not only will the efficiency of the refrigeration cycle 13 decrease due to a decrease in the capacity actually used, but the compressor 8 will suck in the liquid refrigerant that did not evaporate in the refrigerated evaporator 14.

When the compressor 8 sucks in liquid refrigerant, the liquid refrigerant may wash away the lubricating oil on the sliding parts (not shown) inside the compressor 8, causing wear, or the compressor 8 may compress the liquid and damage internal parts, reducing reliability.

At this time, the capacity of the refrigeration evaporator 14 can be fully utilized by reducing the capacity of the compressor 8 or increasing the capacity of the refrigeration fan 16 depending on the temperature detected by the refrigeration chamber sensor 18.

When the temperatures of the refrigerator compartment sensor 18 and freezer compartment sensor 19 fall below a certain temperature, the compressor 8 is stopped and the cooling operation ends.

However, in the above-mentioned conventional refrigerator configuration, in order to raise the evaporation temperature to a temperature suitable for cooling the refrigerator compartment 4, the capacity of the compressor 8 is reduced or the capacity of the refrigerator fan 16 is increased. When the capacity of the compressor 8 is reduced, there are problems such as a decrease in the efficiency of the compressor 8 and an increase in noise, and when the capacity of the refrigerator fan 16 is increased, there are problems such as an increase in the input power of the refrigerator fan 16 and an increase in the noise of the refrigerator fan 16.

The inventors discovered the above problems and came up with the subject matter of this disclosure to solve these problems.

Therefore, the present disclosure provides a refrigerator that can improve the efficiency of the refrigeration cycle when cooling the refrigerator compartment and reduce power consumption.

The following describes the embodiments in detail with reference to the drawings. However, more detailed explanations than necessary may be omitted. For example, detailed explanations of matters that are already well known or duplicate explanations of substantially identical configurations may be omitted.

The accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims.

(Embodiment 1)
Hereinafter, the first embodiment will be described with reference to Figures 1 to 3. Note that the same parts as those in the above-mentioned conventional refrigerator will be given the same reference numerals and the description thereof will be omitted.

[1-1. Configuration]
1 and 2, a refrigerator 20 in this embodiment is composed of an insulated box 21 divided into upper and lower parts by a partition 2, with the space above the partition 2 being a refrigerator compartment 22 in which the interior temperature is maintained at a refrigeration temperature range of approximately 4° C. and the space below the partition 2 being a freezer compartment 23 in which the interior temperature is maintained at a freezing temperature range of approximately −18° C. The front is closed by insulated doors 6 and 7 which can be opened and closed freely.

The backs of the refrigerator compartment 22 and freezer compartment 23 are equipped with a refrigerator evaporator 26 and a freezer evaporator 15, which are connected to the compressor 8, condenser 9, three-way valve 10, refrigerator capillary 11, freezer capillary 12, and check valve 24 to form a refrigeration cycle 25, as well as a refrigerator fan 16 and a freezer fan 17 that circulate the cold air generated by each evaporator into the refrigerator compartment 22 and freezer compartment 23.

The outlet pipes 26a, 15a of the refrigerating evaporator 26 and the freezing evaporator 15 are connected to the compressor 8.

Furthermore, inside the refrigerator compartment 22 and the freezer compartment 23, there are a refrigerator compartment sensor 18 and a freezer compartment sensor 19 that measure the temperature inside each storage compartment.

A heat storage material 27 is provided near the refrigerated evaporator 26. The heat storage material 27 is made by filling a resin case (not shown) with a highly water-absorbent resin whose freezing point is lower than the temperature of the refrigerated compartment 22 and higher than the temperature of the freezer compartment 23, for example, -5°C, and is in thermal contact with the inlet pipe 28 of the refrigerated evaporator 26.

[1-2. Operation]
An example of the operation and function of the refrigerator according to the first embodiment configured as above will be described below with reference to FIG.

As shown in FIG. 3, when the cooling operation starts, the refrigerator switches between freezer cooling mode, refrigerator cold storage mode, and refrigerator cold release mode based on the temperatures detected by the refrigerator sensor 18 and the freezer sensor 19.

First, we will explain the freezer cooling mode. When the refrigerator sensor 18 is below a certain temperature and the freezer sensor 19 is above a certain temperature, the freezer cooling mode is activated.

In freezer cooling mode, the high-temperature, high-pressure gas refrigerant compressed by the compressor 8 is cooled in the condenser 9 to become a low-temperature, high-pressure liquid refrigerant. This liquid refrigerant flows through the freezer capillary 12 via the three-way valve 10, and becomes a low-temperature, low-pressure gas-liquid two-layer refrigerant that flows to the freezer evaporator 15.

The refrigerant that flows into the freezer evaporator 15 evaporates through heat exchange with the air in the freezer compartment 23, generating cold air using the heat of vaporization. The gas refrigerant that leaves the freezer evaporator 15 flows through the check valve 24 and is sucked back into the compressor 8.

The cold air generated at this time is circulated through the freezer compartment 23 by the freezer fan 17, cooling the freezer compartment 23, and when the freezer compartment sensor 19 drops below a certain temperature, the freezer compartment cooling mode ends.

Next, the refrigerator compartment cold storage mode will be explained. The refrigerator compartment cold storage mode is activated when the refrigerator compartment sensor 18 is at or above a certain temperature, the freezer compartment sensor 19 is at or below a certain temperature, and the heat storage material 27 is melted.

During the cold storage mode, the high-temperature, high-pressure gas refrigerant compressed by the compressor 8 is cooled in the condenser 9 to become a low-temperature, high-pressure liquid refrigerant. This liquid refrigerant flows through the refrigeration capillary 11 via the three-way valve 10, and becomes a low-temperature, low-pressure gas-liquid two-layer refrigerant that flows to the refrigeration evaporator 26.

The refrigerant that flows into the refrigeration evaporator 26 evaporates by exchanging heat with the air in the refrigerator compartment 22, generating cold air using the heat of vaporization, which is then sucked back into the compressor 8.

The cold air generated at this time is circulated through the refrigerator compartment 22 by the refrigerator fan 16, cooling the refrigerator compartment 22, and when the refrigerator compartment sensor 18 falls below a certain temperature, the refrigerator compartment cold storage mode ends.

At the same time, the heat storage material 27 exchanges heat with the inlet pipe 28 of the refrigerated evaporator 26. At this time, the temperature of the inlet pipe 28 is below -5°C, which is the freezing point of the heat storage material 27, and the heat storage material 27 solidifies.

When cooling the refrigerator compartment 22, the temperature is in the refrigeration temperature range of approximately 4°C, and since the air temperature exchanging heat with the refrigeration evaporator 26 is higher than when cooling the freezer compartment 23, the temperature of the refrigeration evaporator 26 is also higher than in freezer compartment cooling mode. As a result, the compression ratio, which is the pressure ratio of the intake gas and discharge gas of the compressor 8, becomes smaller, and the efficiency of the refrigeration cycle 25, which is expressed as the ratio of the input of the compressor 8 to the capacity of the refrigeration evaporator 26, also increases.

On the other hand, as the temperature of the refrigerated evaporator 26 rises, the density of the refrigerant gas sucked into the compressor 8 becomes approximately twice as high as when cooling the freezer compartment 23. This increases the amount of refrigerant circulating through the refrigeration cycle 25, and the capacity of the refrigerated evaporator 26 becomes greater than the load on the refrigerated compartment 22. If the capacity is not fully utilized, not only will the efficiency of the refrigeration cycle 25 decrease due to a decrease in the capacity actually used, but the reliability of the compressor 8 may decrease as the compressor 8 sucks in the liquid refrigerant that did not completely evaporate in the refrigerated evaporator 26.

In contrast, in this embodiment, the capacity of the refrigeration evaporator 26 that is not fully used in cooling the refrigerator compartment 22 can be used as latent heat of solidification when solidifying the heat storage material 27 that is in thermal contact with the inlet pipe 28 of the refrigeration evaporator 26.

Next, the refrigerator compartment cold release mode will be explained. The refrigerator compartment cold release mode is activated when the refrigerator compartment sensor 18 is at or above a certain temperature, the freezer compartment sensor 19 is at or below a certain temperature, and the heat storage material 27 is solidified.

In the refrigerator compartment cold release mode, the compressor 8 is stopped and only the refrigerator fan 16 is operated. At this time, the heat storage material 27 is in a solidified state and is in thermal contact with the refrigerator evaporator 26, so the heat storage material 27 exchanges heat with the air in the refrigerator compartment 22, causing the heat storage material 27 to melt and generate cold air due to the latent heat of fusion. The refrigerator fan 16 then circulates the air in the refrigerator compartment 22, cooling it, and when the refrigerator compartment sensor 18 drops below a certain temperature, the refrigerator compartment cold release mode ends.

When the temperatures of the refrigerator compartment sensor 18 and the freezer compartment sensor 19 fall below a certain temperature, the compressor 8 is stopped and the cooling operation ends.

[1-3. Effects, etc.]
As described above, in this embodiment, the refrigerator 20 includes the refrigerator compartment 22, the freezer compartment 23, the refrigerator evaporator 26, the freezer evaporator 15, the refrigerator capillary 11, the freezer capillary 12, the compressor 8, the condenser 9, the three-way valve 10, and the heat storage material 27. The refrigerator capillary 11 is connected in series to the refrigerator evaporator 26. The freezer capillary 12 is connected in series to the freezer evaporator 15. The compressor 8 is connected to the outlet pipe 26a of the refrigerator evaporator 26 and the outlet pipe 15a of the freezer evaporator 15.

The condenser 9 is connected in series with the discharge pipe 8a of the compressor 8. The three-way valve 10 switches the flow of refrigerant to the refrigerated evaporator 26 and the freezing evaporator 15. The heat storage material 27 is in thermal contact with the inlet pipe 28 of the refrigerated evaporator 26.

This allows the capacity of the refrigeration evaporator 26 to be fully utilized without reducing the capacity of the compressor 8, improving the efficiency of the refrigeration cycle 25 and improving the energy-saving performance of the refrigerator 20 without reducing the efficiency of the compressor 8, increasing the input of the refrigeration fan 16, or increasing noise. In addition, the latent heat of the heat storage material 27 can be used to increase the evaporation temperature when cooling the refrigerator compartment 22.

In addition, in the refrigerator compartment cold storage mode, the cold stored in the heat storage material 27 can cool the refrigerator compartment 22 without operating the compressor 8, shortening the operating time of the compressor 8 compared to conventional refrigerators, resulting in a quieter refrigerator 20. In the above embodiment, the heat storage material 27 is in thermal contact with the inlet pipe 28 of the refrigeration evaporator 26, but it goes without saying that the same effect can be obtained by thermally contacting the outlet pipe 26a of the refrigeration evaporator 26.

In addition, the freezing point of the heat storage material 27 is configured to be lower than the temperature of the refrigerator compartment 22 and higher than the temperature of the freezer compartment 23, so the evaporation temperature of the refrigerator compartment 22 can be raised to an evaporation temperature more suitable for cooling the refrigerator compartment 22.

In this embodiment, the freezing point of the heat storage material 27 has been described as -5°C, but it can be any temperature that can cool the inside of the refrigerator compartment 22 in the refrigerator compartment cold release mode. For example, by setting it to 0°C, the temperature of the refrigerator evaporator 26 can be further increased, and the pressure of the intake gas of the compressor 8 can be increased, thereby further improving the efficiency of the refrigeration cycle 25.

In addition, while the compressor 8 is operating and the refrigerator compartment 22 is being cooled, the heat storage material 27 and the interior of the refrigerator compartment 22 are cooled to store thermal energy in the heat storage material 27, and the next time the refrigerator compartment 22 is cooled, the interior of the refrigerator compartment 22 is cooled using the thermal energy stored in the heat storage material 27. Therefore, the cold energy stored in the heat storage material 27 can be used to cool the interior of the refrigerator compartment 22.

In addition, in this embodiment, the cooling modes have been described as three modes: freezer compartment cooling mode, refrigerator compartment cold storage mode, and refrigerator compartment cold release mode. However, by cooling the refrigerator compartment 22 with the heat storage material 27 during the freezer compartment cooling mode, the refrigerator compartment 22 is always cooled except when the compressor 8 is stopped, so that temperature fluctuations in the refrigerator compartment 22 can be suppressed and the freshness-keeping performance of the stored items in the refrigerator compartment 22 can be improved.

In addition, in this embodiment, the operation of the three-way valve 10 in the refrigerator compartment cold release mode and when the compressor 8 is stopped is not mentioned, but the three-way valve 10 can be selected between a mode in which the refrigerant flows to the refrigerator capillary 11, a mode in which the refrigerant flows to the freezer capillary 12, and a closed state in which the refrigerant does not flow to either the refrigerator capillary 11 or the freezer capillary 12. By closing the three-way valve 10 in the refrigerator compartment cold release mode and when the compressor 8 is stopped, it is possible to prevent the room temperature from rising due to the high-temperature refrigerant on the high-pressure side of the refrigeration cycle 25 flowing to the low-pressure side of the refrigeration evaporator 26 or the freezer evaporator 15 when the compressor 8 is not operating, and improve the efficiency of the refrigeration cycle 25.

This disclosure improves the efficiency of the refrigeration cycle when cooling the refrigerator compartment and reduces power consumption, making it applicable to refrigerators of various types and sizes, including those for home and commercial use.

1, 20 Refrigerator 2 Partition 3, 21 Insulated box 4, 22 Refrigerating compartment 5, 23 Freezer compartment 6, 7 Insulated door 8 Compressor 8a Discharge pipe 9 Condenser (heat radiator)
10 Three-way valve (switching valve)
11 Refrigerated capillary (refrigerated pressure reducing means)
12 Refrigeration capillary (refrigeration pressure reducing means)
13, 25 Refrigeration cycle 14, 26 Refrigerating evaporator 15 Freezing evaporator 15a, 26a Outlet pipe 16 Refrigerating fan 17 Freezing fan 18 Refrigerating chamber sensor 19 Freezing chamber sensor 24 Check valve 27 Heat storage material 28 Inlet pipe

Claims (3)

the refrigerator comprises a refrigerator compartment, a freezer compartment, a refrigerator evaporator, a freezer evaporator, refrigerator pressure reducing means connected in series to the refrigerator evaporator, freezer pressure reducing means connected in series to the freezer evaporator, a compressor connected to an outlet pipe of the refrigerator evaporator and an outlet pipe of the freezer evaporator, a radiator connected in series to a discharge pipe of the compressor, a changeover valve for switching a flow of a refrigerant to the refrigerator evaporator and the freezer evaporator, and a refrigerator fan for circulating cold air within the refrigerator compartment;
The present invention is characterized in that a heat storage material is provided in thermal contact with either the inlet pipe or the outlet pipe of the refrigeration evaporator,
The refrigerator compartment is operated by switching at least among a state in which the compressor is operated to cool the refrigerator compartment, a state in which the compressor is not operated and the refrigerator fan is operated to cool the refrigerator compartment, and a state in which the refrigerator compartment is not cooled;
By operating the compressor to cool the refrigerator compartment, the heat storage material and the interior of the refrigerator compartment are cooled, and thermal energy is stored in the heat storage material. When the refrigerator compartment is next cooled, the compressor is not operated and the refrigerator fan is operated to cool the refrigerator compartment, thereby cooling the interior of the refrigerator compartment using the thermal energy stored in the heat storage material and melting the heat storage material at the same time.
When the compressor is operated to cool the refrigerator compartment, at least a part of the heat storage material is in a melted state, so that the capacity of the refrigeration evaporator that is not fully used in cooling the refrigerator compartment is utilized as latent heat of solidification when solidifying the heat storage material . The refrigerator according to claim 1, characterized in that the freezing point of the heat storage material is lower than the temperature of the refrigerator compartment and higher than the temperature of the freezer compartment. The refrigerator according to claim 1, wherein the state in which the refrigerator compartment is not cooled includes a state in which the compressor is not operated and a state in which the compressor is operated to cool the freezer compartment, and the refrigerator is operated by switching to a state in which the compressor is operated to cool the refrigerator compartment after the state in which the freezer compartment is cooled, or a state in which the refrigerator fan is operated without operating the compressor to cool the refrigerator compartment.

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