JP2000274887A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an air conditioner in which refrigerant can be evaporated efficiently in an air-liquid separator without using a heater, etc., even when a nonazeotrope refrigerant is employed. SOLUTION: A heating pipe 21 is disposed on the bottom of an air-liquid separator 12. When a freezing cycle is formed, refrigerant is fed from an indoor heat exchanger 16 through the heating pipe 21 to the air-liquid separator 12 and when a heat pump cycle is formed, refrigerant is fed from a compressor 11 to the heating pipe 21 thence to the indoor heat exchanger 16. According to the arrangement, refrigerant can be evaporated efficiently in the air-liquid separator 12 without using any heater even when a nonazeotrope refrigerant is employed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerating apparatus using a non-azeotropic mixed refrigerant obtained by mixing refrigerants having different boiling points.

[0002]

2. Description of the Related Art At present, refrigeration systems are used in various technical fields. FIG. 4 is a refrigeration circuit diagram when the refrigeration apparatus is used in an air conditioner or the like. Separator 112, outdoor heat exchanger 113 for exchanging heat between refrigerant and outdoor air, decompression device 114 for decompressing or restricting refrigerant, four-way valve 1 for switching refrigerant circulation path
15. Indoor heat exchanger 11 for exchanging heat between refrigerant and indoor air
6 and the like.

[0003] During the cooling operation, the refrigerant is supplied to the compressor 1.
11, the four-way valve 115 is switched so that the outdoor heat exchanger 113, the pressure reducing device 114, the indoor heat exchanger 116, and the gas-liquid separator 112 are sequentially circulated to form a refrigeration cycle.

Accordingly, the hot gas refrigerant which has been compressed by the compressor 111 to have a high temperature and a high pressure is supplied to the outdoor heat exchanger 11.
3 and is condensed by exchanging heat with the outdoor air.
16.

In the indoor heat exchanger 116, the refrigerant exchanges heat with the indoor air, receives the heat of evaporation from the indoor air and evaporates, and the indoor air is cooled by giving the refrigerant heat of evaporation.
The room is cooled.

[0006] The refrigerant evaporated in the indoor heat exchanger 116 is gas-liquid separated in the gas-liquid separator 112, and only the gaseous refrigerant is supplied to the compressor 111.

On the other hand, during the heating operation, the refrigerant is supplied to the compressor 11.
1. The four-way valve 115 is switched so that the indoor heat exchanger 116, the pressure reducing device 114, the outdoor heat exchanger 113, and the gas-liquid separator 112 are sequentially circulated to form a heat pump cycle.

As a result, the refrigerant that has become a high-temperature and high-pressure hot gas in the compressor 111 exchanges heat with indoor air in the indoor heat exchanger 116 and condenses. The indoor air receives the heat of condensation at this time and the temperature rises to heat the room.

The refrigerant condensed in the indoor heat exchanger 116 is depressurized or throttled by the decompression device 114, exchanges heat with outdoor air in the outdoor heat exchanger 113, evaporates, and is separated into gas and liquid by the gas-liquid separator 112. Only the refrigerant in a gas state is supplied to the compressor 111.

Conventionally, a refrigerant such as R-22 has been used in such a refrigerating apparatus. However, it has been found that R-22 and the like contain chlorine, which has been found to cause ozone layer destruction, and has been regulated. .

Therefore, new refrigerants that do not destroy the ozone layer have been studied, and for example, R-410A and R407C have been proposed.

For example, R407C refrigerant is R32 (boiling point:
(57.7 ° C.) 32%, R125 (boiling point: -48.1)
C) at 25% and R134a (boiling point: -26.3 C) at 5%.
This is a non-azeotropic mixed refrigerant mixed at a ratio of 2%.

However, when a refrigerant such as R407C is used, there is a problem that the composition ratio of the refrigerant gradually changes, particularly during a heating operation, and the refrigeration efficiency and the like decrease.

That is, when the liquid refrigerant is supplied to the compressor 111, the compressor 111 causes liquid compression and causes a failure or the like. Therefore, the gas-liquid separator 112 is provided on the low pressure side of the compressor 111. Thus, only the gas refrigerant is supplied to the compressor 111.

At this time, if a non-azeotropic mixed refrigerant is used as the refrigerant, the refrigerant having a low boiling point will evaporate first in the gas-liquid separator 112. If such a state continues for a long time, the composition of the refrigerant circulating in the refrigeration circuit will be reduced. A change occurs, and the refrigeration efficiency and the like decrease.

In general, the cooling operation is used in summer when the temperature of the air (indoor air) for exchanging heat in the evaporator (indoor heat exchanger 116) is high, so that the indoor heat exchanger 116 sufficiently evaporates the refrigerant. However, since the heating operation is used in winter when the temperature of the air (outside air) for exchanging heat in the evaporator (outdoor heat exchanger 113) is low, the outdoor heat exchanger 11 is used.
3, it may be difficult to sufficiently evaporate the refrigerant.

Therefore, during the heating operation, the above-mentioned change in the composition of the refrigerant is likely to occur.

For this reason, in the air conditioner disclosed in Japanese Patent Application Laid-Open No. Hei 7-190515, the gas-liquid separator 112 is heated by a heater or the like, and only the refrigerant having a low boiling point evaporates preferentially. I try to suppress the change.

[0019]

However, in the above-mentioned conventional configuration, a heater for heating the gas-liquid separator 112, a power supply for driving the heater, a control device for controlling the driving of the heater, and the like are required. As a result, there is a problem that the cost increases and the number of failure factors increases.

Accordingly, the present invention is to provide a refrigeration system that allows a gas-liquid separator to efficiently evaporate a refrigerant without using a heater or the like even when a non-azeotropic refrigerant is used. Aim.

[0021]

Means for Solving the Problems To solve the above problems, the invention according to claim 1 comprises a compressor for compressing a refrigerant, an outdoor unit for exchanging heat between the refrigerant and outside air, and a decompression device for decompressing the refrigerant. And an indoor heat exchanger for exchanging heat between the refrigerant and the indoor air, and a gas-liquid separator for separating the refrigerant into gas and liquid so that the gas refrigerant is supplied to the compressor. In an air conditioner in which a non-azeotropic mixed refrigerant circulates in a circuit to perform a refrigeration cycle and a heating cycle operation, refrigeration is performed by switching a heating pipe that heats a refrigerant stored in a gas-liquid separator and a refrigerant circulation path. When a refrigeration cycle is formed, a refrigerant from an indoor heat exchanger is supplied to a gas-liquid separator through a heating pipe, and when a heat pump cycle is formed, a refrigerant from a compressor is formed. Having a four-way valve that is supplied to the indoor heat exchanger after being supplied to the heating pipe, even if a non-azeotropic refrigerant is used, without using a heater or the like, the gas-liquid separator Thus, the refrigerant is efficiently evaporated.

According to a second aspect of the present invention, the heating pipe is provided so as to be exposed in the bottom space of the gas-liquid separator, and is formed so as to directly heat the refrigerant stored in the space. Features.

According to a third aspect of the present invention, the heating pipe is embedded in the bottom wall of the gas-liquid separator or is closely attached to the bottom wall to heat the refrigerant stored in the gas-liquid separator. It is characterized by being formed in.

According to a fourth aspect of the present invention, the gas-liquid separator comprises:
It is characterized by being covered with a heat insulating material.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a refrigeration circuit diagram when a refrigeration apparatus according to the present invention is applied to an air conditioner, and includes a compressor 11 for compressing a refrigerant, an outdoor heat exchanger 13 for exchanging heat between the refrigerant and outdoor air, and a decompression or decompression of the refrigerant. A squeezing decompression device 14, an indoor heat exchanger 16 for exchanging heat between the refrigerant and indoor air, a gas-liquid separator 12 for performing gas-liquid separation and supplying only a gaseous refrigerant to the compressor 11, a circulation of the refrigerant Four-way valve 15 for switching the road
Etc.

During the cooling operation, the outdoor heat exchanger 1
3 functions as a condenser, switches the four-way valve 15 so that the indoor heat exchanger 16 functions as an evaporator, and during the heating operation, the outdoor heat exchanger 13 functions as an evaporator, and the indoor heat exchanger 16 operates as an evaporator. Four-way valve 15 to act as a condenser
Switch.

FIG. 2 is a view showing a cross-sectional structure of the gas-liquid separator 12. A heating pipe 21 is provided so as to be exposed to a bottom space of the gas-liquid separator 12.

The heating pipe 21 is connected in the middle of the low pressure pipe during the cooling operation, and is connected in the middle of the high pressure pipe during the heating operation.

With such a configuration, during the cooling operation, the refrigerant circulates sequentially through the compressor 11, the outdoor heat exchanger 13, the pressure reducing device 14, the indoor heat exchanger 16, the heating pipe 21, and the gas-liquid separator 12. The refrigeration cycle is formed by switching the four-way valve 15.

The hot gas refrigerant compressed to a high temperature and a high pressure by the compressor 11 is supplied to the outdoor heat exchanger 13 and condenses by exchanging heat with the outdoor air in the outdoor heat exchanger 13.

Thereafter, the refrigerant is decompressed or throttled by the decompression device 14 and supplied to the indoor heat exchanger 16, where the refrigerant exchanges heat with the indoor air and evaporates, and passes through the heating pipe 21 for gas-liquid separation. Is supplied to the vessel 12.

Since the heat of evaporation of the refrigerant is given by the room air, the room air is cooled to cool the room.

At this time, the refrigerant from the indoor heat exchanger 16 is stored in the gas-liquid separator 12, and since this refrigerant is a gas refrigerant almost evaporated in the indoor heat exchanger 16, the gas-liquid separator The gas-liquid separation operation at 12 is not performed substantially.

Therefore, even if the low-temperature refrigerant from the indoor heat exchanger 16 circulates in the heating pipe 21, only the gas refrigerant is supplied to the compressor 11.

On the other hand, during the heating operation, the refrigerant
1. The heat pump cycle is formed by switching the four-way valve 15 so that the heating pipe 21, the indoor heat exchanger 16, the pressure reducing device 14, the outdoor heat exchanger 13, and the gas-liquid separator 12 are sequentially circulated.

The hot gas refrigerant compressed to a high temperature and a high pressure by the compressor 11 is supplied to the indoor heat exchanger 16 through the heating pipe 21 and exchanges heat with the indoor air in the indoor heat exchanger 16. Condenses. Thereby, the room air receives the heat of condensation and is heated to heat the room.

The refrigerant from the indoor heat exchanger 16 is decompressed or throttled by the decompression device 14 and supplied to the outdoor heat exchanger 13.
This outdoor heat exchanger 13 exchanges heat with outside air and evaporates. Thereafter, the refrigerant returns to the compressor 11 via the gas-liquid separator 12.

At this time, if the outside air temperature is low, the outdoor heat exchanger 1
In 3, the refrigerant may not evaporate sufficiently,
In this case, the gas-liquid mixed refrigerant is stored in the gas-liquid separator 12.

However, since the high-temperature and high-pressure hot gas from the compressor 11 is circulated in the heating pipe 21, the refrigerant stored in the gas-liquid separator 12 is heated by the hot gas refrigerant. . Therefore, only the refrigerant having a low temperature does not evaporate first, and it is possible to prevent a change in the composition of the refrigerant circulating in the refrigeration circuit.

In the above description, the heating tube 21 is provided so as to be exposed to the bottom space of the gas-liquid separator 12, but the present invention is not limited to this. For example, as shown in FIG. It may be embedded in the bottom wall 22 of the gas-liquid separator 12 or brazed to the bottom wall 22 to be in close contact therewith.

These are selected from the viewpoint of cost and the like, and the present invention is applicable as long as at least the liquid refrigerant stored in the gas-liquid separator 12 is heated by the heating pipe 21. Is clear from the above description.

Although it is not mentioned whether or not the above-mentioned gas-liquid separator 12 is insulated, the heat supplied by the heating pipe 21 is prevented from leaking to the outside by the heat insulating structure, and the heat It goes without saying that effective use can be achieved.

[0043]

As described above, according to the first aspect of the present invention, when the refrigeration cycle is formed by providing the heating pipe for heating the refrigerant stored in the gas-liquid separator, the indoor heat The refrigerant from the exchanger is supplied to the gas-liquid separator via the heating pipe, and when the heat pump cycle is formed, the refrigerant from the compressor is supplied to the heating pipe and then supplied to the indoor heat exchanger. Therefore, even when a non-azeotropic refrigerant is used, the refrigerant can be efficiently evaporated by the gas-liquid separator without using a heater or the like.

According to the second aspect of the present invention, since the heating tube is provided so as to be exposed to the bottom space of the gas-liquid separator, the refrigerant stored in the space can be directly heated, and the non-azeotropic refrigerant can be heated. Even when a refrigerant is used, the refrigerant can be efficiently evaporated by the gas-liquid separator without using a heater or the like.

According to the third aspect of the present invention, since the heating tube is embedded in the bottom wall of the gas-liquid separator or is provided in close contact with the bottom wall, a case where a non-azeotropic refrigerant is used is provided. Also, the refrigerant can be efficiently evaporated by the gas-liquid separator without using a heater or the like.

According to the fourth aspect of the present invention, since the gas-liquid separator is covered with the heat insulating material, the heat given by the heating pipe can be effectively used.

[Brief description of the drawings]

FIG. 1 is a refrigeration circuit diagram applied to an embodiment of the present invention.

FIG. 2 is a diagram showing a detailed configuration of a gas-liquid separator.

FIG. 3 is a diagram showing a detailed configuration of a gas-liquid separator changed to FIG. 2;

FIG. 4 is a refrigeration circuit diagram applied to the description of the conventional technique.

[Explanation of symbols]

 Reference Signs List 11 compressor 12 gas-liquid separator 13 outdoor heat exchanger 14 pressure reducing device 15 four-way valve 16 indoor heat exchanger 21 heating pipe 22 bottom wall

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor, Mr. Nagasawa, 2-5-5, Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (72) Inventor, Tadashi Kato 2-chome, Keihanhondori, Moriguchi-shi, Osaka No. 5-5 Sanyo Electric Co., Ltd. (72) Inventor Katsuo Uchida 2-5-5 Sanyo Electric Co., Ltd., Sanyo Electric Co., Ltd. (72) Inventor Michiya Harada Keihanhon, Moriguchi, Osaka 2-5-5, Sanyo Electric Co., Ltd.

Claims (4)

[Claims] A compressor for compressing the refrigerant, an outdoor unit for exchanging heat between the refrigerant and outside air, a decompression device for decompressing the refrigerant,
A refrigeration circuit is formed by an indoor heat exchanger for exchanging heat between the refrigerant and room air, and a gas-liquid separator for separating the refrigerant into gas and liquid so that the gas refrigerant is supplied to the compressor. In an air conditioner in which a non-azeotropic mixed refrigerant circulates and performs a refrigeration cycle and a heating cycle operation, a heating pipe that heats the refrigerant stored in the gas-liquid separator, Forming a refrigeration cycle and a heat pump cycle, when the refrigeration cycle is formed, the refrigerant from the indoor heat exchanger is supplied to the gas-liquid separator through the heating pipe, and when the heat pump cycle is formed, An air conditioner comprising: a four-way valve configured to supply a refrigerant from a compressor to the heating pipe after the refrigerant is supplied to the heating pipe. 2. The heating pipe according to claim 1, wherein the heating pipe is provided so as to be exposed in a bottom space of the gas-liquid separator, and is configured to directly heat the refrigerant stored in the space. Item 7. The air conditioner according to Item 1. 3. The heating pipe may be embedded in or closely attached to a bottom wall of the gas-liquid separator so as to heat a refrigerant stored in the gas-liquid separator. The air conditioner according to claim 1, wherein: 4. The air conditioner according to claim 1, wherein the gas-liquid separator is covered with a heat insulating material.