JP2002022289A - Refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refrigerator having an enhanced cycle efficiency and consuming less power. SOLUTION: A refrigeration cycle comprises a compressor 1, a discharge pipe 2, a condenser 3, a drier 4, a decompressing means 5, an evaporator 6, a gas-liquid separator 7 and a suction pipe 8 sequentially connected in order. The condenser 3 is provided with a selector valve 9 and two pipelines 21 and 22, are connected to the selector valve 9. The pipeline 21 is brought into contact with the gas liquid separator in a heat changeable state and then is connected with the drier 4, and on the other hand the pipeline 22 is connected to the drier 4 directly. Part of the condenser may be used as parts of the pipelines 21 and 22 from the selector valve 9. A path allowing heat exchange between the gas liquid separator 7 and the condenser 3 and a normal refrigeration cycle path not effecting heat exchange can be switched.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a compressor and a condenser,
The present invention relates to a refrigerator provided with a refrigeration cycle in which a pressure reducer and an evaporator are sequentially connected.

[0002]

2. Description of the Related Art Conventionally, refrigerators are disclosed, for example, in JP-A-8-24.
As disclosed in Japanese Patent No. 7617, there is a device provided with a refrigeration cycle in which a compressor, a condenser, a decompressor, and an evaporator are sequentially connected. In this type of refrigerator, a gas-liquid separator connected between the evaporator and the compressor is disposed in a machine room in which the compressor is disposed, and the refrigerant in the gas-liquid separator is in a wet state. And a gas-liquid separator and a capillary tube as a decompression means are brought into contact with each other in a heat-exchangeable manner. Thereby, the gas-liquid separator for storing the liquid refrigerant is used for cooling the capillary.

[0003]

However, in the above-mentioned refrigerator, the liquid refrigerant accumulated in the gas-liquid separator is used to lower the temperature of the capillary tube by contact with the capillary tube. There is a problem that the cooling capacity of the gas-liquid separator cannot be fully utilized for replacement.
In addition, the refrigerator usually has to cope with changes in the operating environment such as the outside air temperature, and the amount of refrigerant must be set so that the refrigerant does not run short even when the operating load is large. Then, in the vicinity of the compressor, etc., a gas-liquid separator is installed in the machine room where the temperature is high, and in order to set the refrigerant in the gas-liquid separator so as to be always in a wet state, the amount of the charged refrigerant is further increased. I need to do more. As a result, there is a problem that the pressure of the entire refrigeration cycle is increased, the power consumption is deteriorated, and the temperature of the compressor is increased to lower the reliability.

An object of the present invention is to provide a refrigerator that improves cycle efficiency and reduces power consumption in view of the above problems.

[0005]

SUMMARY OF THE INVENTION The present invention is a refrigerator provided with a refrigeration cycle path in which a compressor, a condenser, a decompressor, an evaporator, and a gas-liquid separator are sequentially connected to circulate a refrigerant. A heat exchange path that contacts the gas-liquid separator from the refrigeration cycle path side between the condenser and the evaporator to perform heat exchange and then returns to the original refrigeration cycle path; And a switching means for switching the flow of the refrigerant from the normal path to the heat exchange path when the gas-liquid two-phase refrigerant flows in the gas-liquid separator. It is characterized by the following.

[0006] The heat exchange path is characterized in that the condenser is brought into contact with the gas-liquid separator, or the pressure-reducing means is brought into contact with the gas-liquid separator.

Further, the refrigerator of the present invention is characterized in that a detecting means for detecting a refrigerant state of the gas-liquid separator is provided. Here, the detecting means is a temperature sensor provided in the evaporator and the gas-liquid separator, or detects a liquid level of a refrigerant provided in the gas-liquid separator. Things.

In the present invention, the switching means switches between a heat exchange path and a normal refrigeration cycle path depending on the state of the refrigerant in the gas-liquid separator. In particular, when the operating load is small and the refrigerant in the gas-liquid two-phase state flows in the gas-liquid separator, the flow of the refrigerant is switched to the heat exchange path, and the refrigerant in the gas-liquid separator is in any other state. Is used as a normal refrigeration cycle path, so that the remaining refrigerant not used for cooling in the gas-liquid separator can lower the condensation temperature and reduce the compression ratio, and vaporize the liquid refrigerant in the gas-liquid separator. As a result, the refrigerant circulation amount can be increased, the cycle efficiency is improved, and the power consumption is reduced.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a refrigerator according to the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram of a refrigeration cycle provided with switching means capable of exchanging heat between a gas-liquid separator and a condenser. FIG. 2 is a schematic diagram of a refrigeration cycle provided with switching means capable of exchanging heat between a gas-liquid separator and a capillary tube. FIG. 3 is a schematic diagram of a refrigeration cycle in which a switching unit capable of exchanging heat between a gas-liquid separator and a condenser is provided, and a temperature sensor is installed in the evaporator and the gas-liquid separator. FIG. 4 is a schematic diagram of a refrigeration cycle in which a switching means capable of exchanging heat between a gas-liquid separator and a capillary tube is provided, and a temperature sensor is provided in the evaporator and the gas-liquid separator. FIG. 5 is a view showing a gas-liquid separator provided with a float sensor as a means for detecting the liquid level of the refrigerant inside.

In FIG. 1, 1 is a compressor, 2 is a discharge pipe, 3 is a condenser, 4 is a dryer, 5 is a decompression means, 6 is an evaporator, 7 is a gas-liquid separator, 8 is a suction pipe,
A refrigeration cycle is formed by connecting them sequentially. The condenser 3 is provided with a switching valve 9 to which two pipes 21 and 22 are connected. This one pipe 21 is connected to the dryer 4 after being brought into contact with the gas-liquid separator 7 in a heat exchange state such as soldering.
The other pipe 22 is directly connected to the dryer 4. The two pipes 21 and 22 from the switching valve 9 may be part of a condenser. The switching valve 9 can switch between a path in which the gas-liquid separator 7 and the condenser 3 exchange heat and an ordinary refrigeration cycle path in which no heat exchange is performed.

Normally, the gas-liquid separator 7 is located at the back of the refrigerator compartment together with the evaporator 6, but the pipe 21 from the switching valve 9 which is in contact with the gas-liquid separator 7 reduces the heat load into the refrigerator. Therefore, it is necessary to arrange the gas-liquid separator 7 at a position where heat load does not occur, for example, in a heat insulating material between the refrigerator and the outer wall of the refrigerator.

Next, the cooling operation of the refrigerator configured as described above will be described. Refrigerators are generally required to be usable in a wide range of operating environments, and adjustment of the amount of refrigerant is mainly performed by a gas-liquid separator 7. When the operating load is large, gaseous refrigerant flows in the gas-liquid separator 7, but when the operating load is small, refrigerant in a gas-liquid two-phase state flows, and the gas-liquid refrigerant does not return to the compressor 1. It is stored in the separator 7. First, a state in which the operation load is small and the liquid refrigerant is present in the gas-liquid separator 7 will be described.

The high-temperature and high-pressure refrigerant discharged from the compressor 1 by the operation of the compressor 1 is sent to the condenser 3 through the discharge pipe 2. The refrigerant radiates heat in the condenser 3 and changes from a gas state to a gas-liquid two-phase state. The switching valve 9 causes the refrigerant to flow through the heat exchange path 21 where the condenser 3 and the gas-liquid separator 7 come into contact, and a part of the condenser 3 comes into contact with the gas-liquid separator 7 through which the low-temperature and low-pressure refrigerant flows. As a result, the heat radiation effect of the condenser 3 increases, and the condensation temperature decreases. As a result, the compression ratio of the compressor 1 is reduced and the cooling capacity is improved, and the COP of the compressor 1 is increased.

Thereafter, the refrigerant passes through the dryer 4 and is decompressed while exchanging heat with the low-temperature suction pipe 8 in the decompressor 5. The evaporator 6 enters a low-temperature low-pressure gas-liquid mixed state.
This refrigerant exchanges heat with the air in the refrigerator, and the dryness increases. At this time, the refrigerant in a gas-liquid mixed state is sent to the gas-liquid separator 7. Since the gas-liquid separator 7 exchanges heat with the heat of the condenser 3, the liquid refrigerant vaporizes and passes through the suction pipe 8. Return to the compressor 1. For this reason, the amount of the liquid refrigerant in the gas-liquid separator 7 decreases, the evaporation pressure increases, the refrigerant circulation amount increases, the compression ratio decreases, etc., so that the COP increases and the power consumption of the refrigerator can be reduced. .

When the operating load is large and the refrigerant enters the gas-liquid separator 7 as a gas, the switching valve 9 is connected to the ordinary refrigeration cycle path 2 where the condenser 3 and the gas-liquid separator 7 do not exchange heat.
Switch to 2. As a result, the condenser 3 heats the refrigerant gas in the gas-liquid separator 7 to prevent the cooling capacity from deteriorating by increasing the specific volume of the gas suctioned into the compressor 1. Therefore, the refrigerant in the gas-liquid separator 7 does not need to be always in a wet state, and it is possible to set an optimum amount of refrigerant to be charged for the refrigeration cycle.

In FIG. 2, a refrigeration cycle similar to that of FIG. 1 is formed, and the same portions are denoted by the same reference numerals. The difference from FIG. 1 is that a switching valve 9 is provided between the dryer 4 and the evaporator 6, and the switching valve 9 is connected to two capillary tubes 10 and 11, which are two pressure reducing means. After the capillary tube 10 is brought into contact with the gas-liquid separator 7 in a heat-exchangeable state such as soldering, the capillary tube 10 is connected to the evaporator 6.
1 is directly connected to the evaporator 6. Thus, the switching valve 9 can be used to switch between a path in which the gas-liquid separator 7 and the capillary exchange heat and a normal refrigeration cycle in which heat exchange does not occur. Normally, the gas-liquid separator 7 is located at the back of the refrigerator compartment together with the evaporator 6 and the like. However, the capillary tube 10 in contact with the gas-liquid separator 7 causes a heat load to the inside of the refrigerator. 7 needs to be arranged at a position where it does not cause a heat load, such as being arranged in a heat insulating material between the refrigerator and the outer wall of the refrigerator.

Next, the cooling operation of the refrigerator configured as described above will be described. When the operating load is small, the high-temperature and high-pressure refrigerant discharged from the compressor 1 is sent to the condenser 3 through the discharge pipe 2 by the operation of the compressor 1.
The refrigerant radiates heat in the condenser 3, changes from a gas state to a gas-liquid two-phase state, and flows from the dryer 4 to the switching valve 9. Then, the refrigerant flows through the capillary tube 10 by the switching valve 9, and a part of the capillary tube 10 comes into contact with the gas-liquid separator 7 through which the low-temperature and low-pressure refrigerant flows, and the refrigerant is reduced in pressure while lowering the temperature.

In the conventional refrigeration cycle, the capacity of the cooling building was increased by contacting the suction pipe 8 during depressurization to lower the temperature, but in the present invention, heat exchange is performed not only with the suction pipe 8 but also with the gas-liquid separator 7. Therefore, the cooling capacity of the refrigeration cycle can be further increased, and the power consumption can be reduced.

The operation load is large, and the gas-liquid separator 7
When the refrigerant enters the gaseous state into the capillary 11
To the path that flows. Thereby, the capillary tube 10 can heat the refrigerant gas in the gas-liquid separator 7 and prevent the cooling capacity from deteriorating due to the increase in the specific volume of the gas sucked into the compressor 1. Therefore, the refrigerant in the gas-liquid separator 7 does not need to be always in a wet state, and it is possible to set an optimum amount of refrigerant to be charged for the refrigeration cycle.

In the refrigeration cycles of FIGS. 3 and 4, the same parts as those of FIGS. 1 and 2 are denoted by the same reference numerals. The difference from FIGS. 1 and 2 is that the temperature sensors 12 and 13 are arranged. The temperature sensor 12 can detect the temperature of the refrigerant in the evaporator 6, and the temperature sensor 13 can detect the temperature of the refrigerant in the gas-liquid separator 7.

When the operation load is small and the liquid refrigerant is accumulated in the gas-liquid separator 7, the refrigerant temperatures at the temperature sensor 12 and the temperature sensor 13 become equal. Therefore, in FIG. 3, the switching valve 9 is controlled so that the refrigerant flows in a path in which the condenser 3 and the gas-liquid separator 7 exchange heat, and in FIG. 4, a refrigerant flows in a path in which the capillary tube 10 exchanges heat with the gas-liquid separator 7.

If the operating load is large and the refrigerant enters the gas-liquid separator 7 in a gaseous state, the temperature sensor 13
Indicates a temperature higher than the temperature sensor 12. Therefore, FIG.
In FIG. 4, the switching valve 9 is controlled so that the refrigerant flows in a path in which the condenser 3 and the gas-liquid separator 7 do not exchange heat, and in FIG.

As shown in FIG. 5, a float sensor 14 is provided inside the gas-liquid separator 7 as means for detecting the liquid level of the refrigerant. The presence or absence of liquid refrigerant in the gas-liquid separator 7 is detected by the float of the float sensor 14, and when liquid refrigerant is present,
The switching valve 9 is controlled so that the heat exchange between the liquid refrigerant and the condenser 3 or the capillary tube 10 does not occur, and when there is no liquid refrigerant, the heat exchange does not occur.

[0024]

The refrigerator of the present invention is used for cooling the inside of the gas-liquid separator because the flow of the refrigerant is switched to the heat exchange path when the gas-liquid two-phase refrigerant in the gas-liquid separator flows. The remaining refrigerant lowers the condensation temperature, lowers the compression ratio, evaporates the liquid refrigerant in the gas-liquid separator, increases the refrigerant circulation, improves cycle efficiency, and reduces power consumption. Is reduced. Also, by the refrigerant in the gas-liquid separator, the capillary temperature can be reduced,
Since the cooling capacity is increased and the operation rate is reduced, the power consumption is reduced. When the liquid refrigerant does not accumulate in the gas-liquid separator, the switching valve stops heat exchange between the condenser and the capillary and the gas-liquid separator. An increase due to heat exchange with the refrigerant in the separator does not occur, so that deterioration in cycle efficiency can be prevented.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a refrigeration cycle provided with switching means capable of exchanging heat between a gas-liquid separator and a condenser of the present invention.

FIG. 2 is a schematic diagram of a refrigeration cycle provided with switching means capable of exchanging heat between a gas-liquid separator of the present invention and a capillary tube.

FIG. 3 is a schematic diagram of a refrigeration cycle in which a switching unit capable of exchanging heat between a gas-liquid separator and a condenser according to the present invention is provided, and a temperature sensor is installed in an evaporator and a gas-liquid separator unit.

FIG. 4 is a schematic diagram of a refrigeration cycle in which a switching means capable of exchanging heat between a gas-liquid separator and a capillary tube of the present invention is provided, and a temperature sensor is provided in an evaporator and a gas-liquid separator.

FIG. 5 is a view showing a gas-liquid separator provided with a float sensor as a means for detecting the liquid level of the refrigerant inside the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Compressor 2 Discharge pipe 3 Condenser 4 Dryer 5 Decompressor 6 Evaporator 7 Gas-liquid separator 8 Suction pipe 9 Switching valve 10, 11 Capillary tube 12, 13 Temperature sensor 14 Float sensor

Claims (6)

[Claims] 1. A refrigerator provided with a refrigeration cycle path in which a compressor, a condenser, a decompressor, an evaporator, and a gas-liquid separator are sequentially connected to circulate a refrigerant, wherein the refrigeration cycle between the condenser and the evaporator is provided. A heat exchange path that contacts the gas-liquid separator from the path side to perform heat exchange and then returns to the original refrigeration cycle path; a normal path that is a normal refrigeration cycle path that does not pass through the heat exchange path; A refrigerator provided with switching means for switching the flow of the refrigerant from a normal path to the heat exchange path when a refrigerant in a gas-liquid two-phase state flows in the gas-liquid separator. 2. The refrigerator according to claim 1, wherein the heat exchange path contacts the gas-liquid separator from the condenser. 3. The refrigerator according to claim 1, wherein the heat exchange path is brought into contact with the gas-liquid separator from the decompression means. 4. The refrigerator according to claim 1, further comprising detecting means for detecting a refrigerant state of the gas-liquid separator. 5. The refrigerator according to claim 4, wherein said detecting means is a temperature sensor provided in said evaporator and said gas-liquid separator. 6. The refrigerator according to claim 4, wherein the detecting means detects a liquid level of a refrigerant provided in the gas-liquid separator.