JPH09196489A - Refrigeration cycle for air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an economical air conditioner using a non-azeotrope mixed refrigerant, and improve the efficiency by a method wherein a passage switching valve is inserted in the suction port and the discharge port of an indoor heat- exchanger, and the direction of a refrigerant flow of the indoor heat-exchanger is made uniform regardless of the cooling and heating operations, and the regrigerant flow is made into a countercurrent flow to the air direction. SOLUTION: The discharge port of a compressor 1 is connected to the suction port of an indoor heat-exchanger 5 by a first 4-way valve 2 and a second 4-way valve 6. Then, the suction port of the compressor 1 is connected to the discharge port of the indoor heat-exchanger 5 by the first 4-way vale 2 and the second 4-way valve 6. One side of a decompressor 4 is connected to the suction port of the indoor heat-exchanger 5 by the second 4-way valve 6, and the other side is connected to the other port of an outdoor heat-exchanger 3. Also, the decompressor 4 is constituted in such a manner that two capillary tubes 4a, 4b for cooling being connected in parallel, are serially connected to a capillary tube 4c for heating and a reverse current preventive valve 4d being arranged so as to flow in the normal direction at the time of cooling, which are connected in parallel.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerating cycle of an air conditioner, and more particularly to a non-azeotropic mixed refrigerant in which two or more kinds of refrigerants having different boiling points are mixed at a predetermined ratio.

[0002]

2. Description of the Related Art Conventionally, a refrigerating cycle of an air conditioner used for cooling and heating uses a single refrigerant such as R22 as a refrigerant, and as shown in the refrigerating cycle diagram of FIG. A refrigerating cycle in which the decompressor 4 and the evaporator are sequentially connected is configured, and the refrigerant from the compressor 1 is switched to the indoor heat exchanger 5 or the outdoor heat exchanger 3 by the four-way valve 2, whereby the indoor heat exchanger 5 Alternatively, the outdoor heat exchanger 3 is switched to a condenser or an evaporator, and the indoor heat exchanger 5 and the outdoor heat exchanger 3 are used by being blown in a certain direction by the fans 7 and 8. As shown in the Ph (Mollier) diagram of FIG. 6-a, the characteristic of the conventional refrigerant is that the isotherm is almost horizontal and has no temperature gradient in the gas-liquid two-layer state. The temperatures of the refrigerant on the inlet side and the outlet side are almost constant, and the heat exchange efficiency does not change much even if air is ventilated from either the inlet side or the outlet side of the heat exchanger. As shown in FIG. 5-a, the exchanger was a counter flow, and as the evaporator, the heat exchanger was a parallel flow as shown in FIG. 5-b. In recent years, from the standpoint of protecting the global environment, regulations on CFCs that destroy the ozone layer have been strengthened, and non-azeotropic mixed refrigerants in which two or more kinds of refrigerants are mixed are regarded as promising as alternative refrigerants. However, the characteristic of the above non-azeotropic mixed refrigerant is that the isotherm in the gas-liquid two-layer state has a downward slope to the right and has a temperature gradient as shown in the Ph (Mollier) diagram of FIG. 6-b. There is. When a refrigerant with such a temperature gradient characteristic is passed through a heat exchanger in a conventional refrigeration cycle, there is a difference in the temperature of the refrigerant on the inlet side and the outlet side of the heat exchanger, so the ventilation direction and the refrigerant flow direction are different. Have different heat exchange efficiencies between the same so-called parallel flow and the so-called counter flow in which the direction of air flow and the direction of flow of the refrigerant are opposite. It is well known that the exchange efficiency is significantly reduced. As described above, when the non-azeotropic mixed refrigerant is used in the refrigeration cycle of the conventional air conditioner, there is a problem that the heat exchange efficiency on the evaporator side is reduced.

In order to solve the above-mentioned drawbacks, as shown in the refrigeration cycle diagram shown in FIG. 8, the discharge port of the compressor 1 is connected to the suction port of the indoor heat exchanger 5 and the outdoor heat via the first four-way valve 2. The inlet of the compressor 3 is connected to the inlet of the compressor 3, and the inlet of the compressor 1 is connected to the outlet of the indoor heat exchanger 5 and the outlet of the outdoor heat exchanger 3 via the second four-way valve 12. The outlet of the decompressor 40 is connected to the inlet of the indoor heat exchanger 5 and the inlet of the outdoor heat exchanger 3 via the first four-way valve 2, and the inlet of the decompressor 40 is the second four-way. The indoor heat exchanger 5 and the outdoor heat exchanger 3 are connected to the outlet of the indoor heat exchanger 5 and the outlet of the outdoor heat exchanger 3 via the valve 12.
It has been considered that the direction of the refrigerant flow flowing in is constant regardless of whether it is during cooling or during heating, and the refrigerant flow is opposed to the wind direction. However, in this refrigerant circuit, the direction of the refrigerant flowing through the decompressor 40 is constant regardless of whether it is in cooling or heating. However, since it is necessary to change the characteristic (the degree of throttling) of the pressure reducer 40 during cooling and during heating, the pressure reducer 40
However, there is no choice but to use an electrically controllable one such as an electronic expansion valve, which has been a cause of increasing the cost.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems and provide an inexpensive and efficient refrigeration cycle for an air conditioner using a non-azeotropic mixed refrigerant.

[0005]

In order to solve the above-mentioned problems, the present invention uses a non-azeotropic mixed refrigerant in which two or more kinds of refrigerants having different boiling points are mixed at a predetermined ratio, and a compressor, a four-way valve, A refrigeration cycle in which a condenser, a decompressor, and an evaporator are sequentially connected is configured, and the refrigerant discharged from the compressor is switched to an indoor heat exchanger or an outdoor heat exchanger by a four-way valve to flow through the indoor heat exchanger. Switch to condenser or evaporator,
An air conditioner used for cooling and heating by ventilating the indoor heat exchanger and the outdoor heat exchanger in a certain direction by a fan to exchange heat, the first invention is the suction port of the indoor heat exchanger. And insert a flow path switching valve at the discharge port,
The direction of the refrigerant flow in the indoor heat exchanger is constant regardless of cooling and heating, and the refrigerant flow is in a so-called counterflow direction opposite to the wind direction.

In the air conditioner of the above, a second aspect of the present invention is to install a flow path switching valve at the intake port and the discharge port of the indoor heat exchanger and the outdoor heat exchanger so as to provide the indoor heat exchanger and the outdoor heat exchanger. The direction of the refrigerant flow in the vessel was constant regardless of cooling and heating, and the refrigerant flow was a so-called counter flow, which was the opposite direction to the wind direction.

Further, the flow path switching valve is a four-way valve or
It is configured by four check valves that are piped in a bridge shape.

[0008]

With the above construction, in the refrigeration cycle of the air conditioner of the first aspect of the present invention, the refrigerant that is compressed by the compressor to raise the temperature and is discharged during cooling is the outdoor heat exchanger. After lowering the enthalpy by exchanging heat with air, the temperature is reduced by a decompressor composed of a capillary tube and a backflow prevention valve that has characteristics matching for cooling, and the temperature is lowered. Is sucked into the suction port of the indoor heat exchanger through the flow path switching valve composed of the check valve of
The indoor heat exchanger exchanges heat with air to raise the enthalpy and discharges it from the discharge port so that it is circulated to the four-way valve and the compressor through the flow path switching valve. The refrigerant that is compressed and raises the temperature is discharged to the intake port of the indoor heat exchanger through the four-way valve or the flow path switching valve that is composed of four check valves that are piped in the shape of a bridge, and the indoor heat exchange is performed. After exchanging heat with air in the heater to lower the enthalpy, it is sent to a pressure reducer composed of a capillary tube and a backflow prevention valve through the flow path switching valve and matched in characteristics for heating, and the pressure is reduced by the pressure reducer. The temperature is lowered, and the outdoor heat exchanger exchanges heat with air to raise the enthalpy so that it is circulated to the compressor through a four-way valve. Therefore, the refrigerant flow direction in the indoor heat exchanger is constant during both cooling and heating, and the refrigerant flow direction and the ventilation direction are opposite, so that the heat exchange efficiency of the indoor heat exchanger is increased as a so-called counterflow. There is.

In the first aspect of the invention, the flow direction of the refrigerant flowing through the indoor heat exchanger is set to be constant during both cooling and heating. However, in the refrigeration cycle of the air conditioner according to the second aspect of the invention, Similar to the first aspect of the invention, during cooling and heating, the direction of the refrigerant flowing through the indoor heat exchanger is constant, and the direction of the refrigerant flowing through the outdoor heat exchanger is also constant, so that the direction of the refrigerant and the direction of ventilation are opposite. As a counter flow, the heat exchange efficiency of the indoor heat exchanger and the outdoor heat exchanger is increased.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an air conditioner according to the present invention will be described in detail with reference to the drawings. FIG. 1 is a refrigeration cycle diagram showing an embodiment of a refrigeration cycle of an air conditioner according to the present invention.
As shown in FIG. 1, the refrigerating cycle of the air conditioner according to the present invention, which uses a non-azeotropic mixed refrigerant in which two or more kinds of refrigerants having different boiling points are mixed at a predetermined ratio, is used for both cooling and heating. One discharge port is connected to one port of the outdoor heat exchanger 3 via the first four-way valve 2 and an intake port of the indoor heat exchanger 5 via the first four-way valve 2 and the second four-way valve 6. Connected, and the suction port of the compressor 1 has a first four-way valve 2 and a second four-way valve 6
Is connected to the discharge port of the indoor heat exchanger 5 via the first four-way valve 2 and the other port of the outdoor heat exchanger 3 via the first four-way valve 2. One of the pressure reducers 4 is connected to the second four-way valve 6. Through the indoor heat exchanger 5
Of the outdoor heat exchanger 3 is connected to the other inlet of the outdoor heat exchanger 3. Further, the outdoor heat exchanger 3 and the indoor heat exchanger 5 are ventilated in a certain direction by the fan 7 or the fan 8 to accelerate the heat exchange between the air and the refrigerant. Further, the decompressor 4 is connected to two cooling capillary tubes 4a connected in parallel, in which a heating capillary tube 4c and a check valve 4d arranged so as to flow forward in cooling are connected in parallel. Are configured.

FIG. 2 is a refrigeration cycle diagram showing another embodiment of the refrigeration cycle of the air conditioner according to the present invention. In this embodiment, the discharge port of the compressor 1 is the first four-way valve 2 and the third four-way valve.
Through the four-way valve 61 of the outdoor heat exchanger 3 and the first
Is connected to the intake port of the indoor heat exchanger 5 via the four-way valve 2 and the second four-way valve 6, and the intake port of the compressor 1 is indoors via the first four-way valve 2 and the second four-way valve 6. The outlet of the heat exchanger 5 is connected to the outlet of the outdoor heat exchanger 3 via the first four-way valve 2 and the third four-way valve 61, and the pressure reducer 4
One is connected to the inlet of the indoor heat exchanger 5 via the second four-way valve 6 and the outlet of the indoor heat exchanger 5, and the other of the pressure reducer 4 is connected to the outdoor heat exchange via the third four-way valve 61. It is connected to the inlet of the vessel 3 and the outlet of the outdoor heat exchanger 3.

FIGS. 3 and 4 respectively show the second four-way valve 6 and the third four-way valve 61 in the embodiment of FIGS. 1 and 2 as a check valve 16a, a check valve 16b, and a check valve. 16
c, four check valves 16d, or check valves 26
An example is shown in which four valves, a, a check valve 26b, a check valve 26c, and a check valve 26d are bridge-connected to form a flow path switching valve.

The flow and operation of the refrigerant in the refrigerating cycle of the air conditioner according to the present invention having the above structure will be described below. First, the configuration of FIG. 1 will be described. During the cooling operation, the refrigerant which is compressed by the compressor 1 to raise the temperature and is discharged flows into the outdoor heat exchanger 3 by switching the flow path by the first four-way valve 2. In the outdoor heat exchanger 3, after exchanging heat with the air blown by the fan 7 to lower the enthalpy, the pressure is reduced by the pressure reducer 4 to lower the temperature, and the temperature of the indoor heat exchanger 5 is reduced via the second four-way valve 6. The second four-way valve 6 and the first four-way valve are sucked into the suction port 5a, exchange heat with the air blown from the fan 8 in the indoor heat exchanger 5 to raise enthalpy, and are discharged from the discharge port 5b. It is circulated to the compressor 1 via 2.

Further, in the configuration of FIG. 1, during the heating operation, the refrigerant compressed by the compressor 1 to raise the temperature and to be discharged is switched by the first four-way valve 2 and the second four-way valve 6. The enthalpy is lowered by exchanging heat with the air that has flowed into the suction port 5a of the indoor heat exchanger 5 and is blown from the fan 8 in the indoor heat exchanger 5, and then the decompressor via the second four-way valve 6. 4 and the pressure is reduced by the pressure reducer 4 to lower the temperature,
Further, the outdoor heat exchanger 3 exchanges heat with the air blown by the fan 7 to raise the enthalpy and is circulated to the compressor 1 via the four-way valve. As described above, regardless of cooling or heating, the refrigerant is sucked through the suction port 5a of the indoor heat exchanger and discharged through the discharge port 5b, so that the refrigerant flow direction becomes constant, and as shown in FIG. In addition, the heat exchange efficiency of the indoor heat exchanger can be increased in both cooling and heating as a so-called counter flow in which the direction of the refrigerant flow and the direction of ventilation are opposite.

Next, the configuration of FIG. 4 will be described. During the cooling operation, the refrigerant that is compressed by the compressor 1 and whose temperature is raised and discharged is switched to the suction port 3a of the outdoor heat exchanger 3 through the check valve 26a after switching the flow path by the first four-way valve 2. Be flowed in. In the outdoor heat exchanger 3, after exchanging heat with the air blown by the fan 7 to lower the enthalpy, it flows into the pressure reducer 4 from the discharge port 3b through the check valve 26d and is reduced in pressure by the pressure reducer 4. Reduce temperature, check valve 1
Is sucked into the suction port 5a of the indoor heat exchanger 5 via 6b,
The indoor heat exchanger 5 exchanges heat with the air blown by the fan 8 to raise the enthalpy and is discharged from the discharge port 5b.
It is circulated to the compressor 1 via the check valve 16c and the first four-way valve 2.

In the configuration of FIG. 4, during the heating operation, the refrigerant compressed by the compressor 1 to raise the temperature and to be discharged is switched by the first four-way valve 2 and the backflow prevention valve 16a to switch the indoor heat. After the heat is exchanged with the air blown from the fan 8 in the indoor heat exchanger 5 into the suction port 5a of the exchanger 5 to lower the enthalpy, it is sent to the pressure reducer 4 via the check valve 16d. The pressure is reduced by the pressure reducer 4 to lower the temperature,
Intake port 5a of the outdoor heat exchanger 3 via the check valve 26b
To the backflow preventive valve 2 by exchanging heat with the air that has flowed into the outdoor heat exchanger 3 and is blown by the fan 7 in the outdoor heat exchanger 3.
6c, is circulated to the compressor 1 via the first four-way valve 2.

FIGS. 3 and 4 show the four-way valve of FIGS. 1 and 2 constructed by connecting four check valves in a bridge connection.
The operation of FIG. 4 is basically the same as that of FIG. 3, and the description thereof is omitted.

As described above, the refrigerant is drawn in through the suction port 5a of the indoor heat exchanger and discharged through the discharge port 5b regardless of whether it is cooling or heating, and the suction port 3 of the outdoor heat exchanger.
Since it is sucked from a and discharged from the discharge port 3b, the refrigerant flow direction is constant, and as shown in FIG. 5-a, the refrigerant flow direction and the ventilation direction are opposite to each other, that is, as a so-called counterflow, both during cooling and during heating. The heat exchange efficiency of the indoor heat exchanger and the outdoor heat exchanger can be improved.

[0019]

As described above, according to the refrigerating cycle of the air conditioner according to the present invention, the refrigerant flow is drawn from the suction port of the heat exchanger and discharged from the discharge port regardless of cooling or heating. Therefore, the flow direction of the refrigerant in the heat exchanger becomes constant, so that the flow direction of the refrigerant and the ventilation direction can be opposite, that is, so-called counterflow, and two or more kinds of refrigerants having different boiling points are mixed at a predetermined ratio. Even if the mixed refrigerant is used, the heat exchange efficiency of the indoor heat exchanger and the outdoor heat exchanger can be improved both during cooling and heating, and the decompressor is an electrically controlled component such as an electronic expansion valve. It is possible to provide a refrigeration cycle for an air conditioner that is inexpensive and has good heat exchange efficiency because it can be configured with a capillary tube and a check valve without using the.

[Brief description of drawings]

FIG. 1 is a refrigeration cycle diagram showing an embodiment of a refrigeration cycle of an air conditioner according to the present invention.

FIG. 2 is a refrigeration cycle diagram showing another embodiment of the refrigeration cycle of the air conditioner according to the present invention.

FIG. 3 is a refrigeration cycle diagram showing another embodiment of the refrigeration cycle of the air conditioner according to the present invention.

FIG. 4 is a refrigeration cycle diagram showing another embodiment of the refrigeration cycle of the air conditioner according to the present invention.

FIG. 5 is a diagram illustrating a counter flow and a parallel flow.

FIG. 6 is a Ph (Mollier) diagram of a conventional refrigerant and a non-azeotropic mixed refrigerant.

FIG. 7 is a refrigeration cycle diagram showing a refrigeration cycle of a conventional air conditioner.

FIG. 8 is a refrigeration cycle diagram showing another example of the refrigeration cycle of the conventional air conditioner.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Compressor 2 First four-way valve 3 Outdoor heat exchanger 4 Decompressor 4a Cooling capillary tube 4b Cooling capillary tube 4c Heating capillary tube 4d Backflow prevention valve 5 Indoor heat exchanger 6 Second four-way valve 7 Fan 8 Fan 16a Backflow prevention valve 16b Backflow prevention valve 16c Backflow prevention valve 16d Backflow prevention valve 26a Backflow prevention valve 26b Backflow prevention valve 26c Backflow prevention valve 26d Backflow prevention valve

Claims (4)

[Claims] 1. A refrigeration cycle in which a compressor, a four-way valve, a condenser, a pressure reducer, and an evaporator are sequentially connected using a non-azeotropic mixed refrigerant in which two or more kinds of refrigerants having different boiling points are mixed at a predetermined ratio. The refrigerant discharged from the compressor is switched to an indoor heat exchanger or an outdoor heat exchanger by a four-way valve to flow, thereby switching the indoor heat exchanger to a condenser or an evaporator.
In the air conditioner used for cooling and heating, air is passed through the indoor heat exchanger and the outdoor heat exchanger in a certain direction by a fan to exchange heat, so that a flow path is provided to the intake port and the discharge port of the indoor heat exchanger. A refrigeration of an air conditioner, characterized in that a switching valve is inserted to make the direction of the refrigerant flow of the indoor heat exchanger constant irrespective of heating and cooling, and the refrigerant flow is in a so-called counterflow direction opposite to the wind direction. cycle. 2. A refrigeration cycle in which a compressor, a four-way valve, a condenser, a pressure reducer, and an evaporator are sequentially connected by using a non-azeotropic mixed refrigerant in which two or more kinds of refrigerants having different boiling points are mixed in a predetermined ratio. The refrigerant discharged from the compressor is switched to an indoor heat exchanger or an outdoor heat exchanger by a four-way valve to flow, thereby switching the indoor heat exchanger to a condenser or an evaporator.
In the air conditioner used for cooling and heating, air is blown into the indoor heat exchanger and the outdoor heat exchanger in a certain direction by a fan to exchange heat, and thus, the intake ports of the indoor heat exchanger and the outdoor heat exchanger and A flow path switching valve was inserted at the discharge port, and the direction of the refrigerant flow of the indoor heat exchanger and the outdoor heat exchanger was made constant regardless of cooling and heating, and the refrigerant flow was in the opposite direction to the wind direction, so-called counterflow. A refrigeration cycle for an air conditioner, which is characterized in that 3. The refrigeration cycle for an air conditioner according to claim 1, wherein the flow path switching valve is a four-way valve. 4. The refrigerating cycle for an air conditioner according to claim 1, wherein the flow path switching valve is constituted by four check valves which are arranged in a bridge shape.