JP2002022307A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an air conditioner utilizing effectively a condensation heat exchanger upon cooling operation and heating operation. SOLUTION: The air conditioner, in which a compressor 1, an indoor heat exchanger 8, a reducer 4, a liquid receiver 5 and an outdoor heat exchanger 3 are connected through a pipeline, is provided with the condensation heat exchanger 6 arranged so as to be positioned at the outlet port side of the liquid receiver 5 upon cooling operation while the same is positioned at the inlet port side of the liquid receiver 5 upon heating operation to permit heat exchange between the condensation heat exchanger 6 and the lower part of the outdoor heat exchanger 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner, and more particularly, to an air conditioner having a liquid receiver, which is suitable for improving the performance, saving power, and simplifying a refrigeration cycle.

[0002]

2. Description of the Related Art As a method of improving the performance and power saving of an air conditioner, there is a method of reducing a pressure loss on a low pressure side. One of the methods is to attach the excess refrigerant to a suction side of a compressor in which excess refrigerant is stored. It is known that an accumulator is abolished, a liquid receiver is provided in a high pressure part or an intermediate pressure part of a refrigeration cycle, and excess refrigerant is stored in the liquid receiver. in this way,
By eliminating the accumulator attached to the low pressure side of the compressor, the pressure loss on the low pressure side is reduced, and the amount of refrigerant circulating in the refrigeration cycle is increased due to an increase in the suction pressure of the compressor, so that the capacity can be improved.

[0003] Further, since no liquid refrigerant is stored on the compressor suction side, the refrigerant state of the compressor suction can be overheated.
The efficiency of the compressor is improved, and power can be saved. However, the liquid refrigerant condensed in the condenser becomes a saturated liquid state in the receiver and flows out of the receiver, flows into the evaporator and evaporates. The amount of latent heat cannot be increased so that the performance cannot be further improved.

In order to improve the thermal efficiency of the refrigeration cycle so as to improve the capacity and save power, a condensing heat exchanger is provided downstream of the receiver during cooling operation, and the saturation heat flowing out of the receiver is used. Japanese Patent Application Laid-Open No. 2000-11174 describes, for example, Japanese Patent Application Laid-Open No. 2000-11174 that heat exchange of a liquid state refrigerant with air to supercool the refrigerant and increase the amount of latent heat in an evaporator.

[0005]

The above-mentioned conventional technique for improving the capacity is based on the position of a condensing heat exchanger and an outdoor heat exchanger disposed downstream of a receiver provided for supercooling the refrigerant. Has not been taken into account. Therefore, during the heating operation, the refrigerant flows into the condensing heat exchanger that supercools the refrigerant, exchanges heat with the air passing through the condensing heat exchanger, and radiates heat only to the outside air. Throw it away.

Further, in order to eliminate heat discarded in the condensing heat exchanger, a liquid receiver and a condensing heat exchanger are connected so that no refrigerant passes through the condensing heat exchanger or the condensing heat exchanger is used as an evaporator. A method of disposing a check valve, an expansion valve, and the like in the middle of the piping to selectively flow the refrigerant through the condensation heat exchanger complicates the refrigeration cycle and increases the production cost. In addition, since the condensing heat exchanger is provided separately from the outdoor heat exchanger, manufacturing costs for the condensing heat exchanger and the connection piping are increased.

SUMMARY OF THE INVENTION An object of the present invention is to solve the conventional technical problem and to provide a condensing heat exchanger for supercooling a refrigerant downstream of a liquid receiver, even in a cooling operation and a heating operation. An object of the present invention is to provide an air conditioner that effectively utilizes a condensing heat exchanger. Another object of the present invention is to reduce the manufacturing cost without complicating the refrigeration cycle.

[0008]

In order to achieve the above object, the present invention relates to an air conditioner in which a compressor, an indoor heat exchanger, a pressure reducing device, a liquid receiver, and an outdoor heat exchanger are connected by piping. In the cooling operation, a condenser heat exchanger is provided at the outlet side of the receiver during the cooling operation, and is provided at the inlet side of the receiver during the heating operation, and the condenser heat exchanger is provided as an outdoor heat exchanger. It allows heat exchange with the lower part.

Further, in the present invention, it is preferable that the lower part of the outdoor heat exchanger is the condensing heat exchanger.

Further, in the above, the number of refrigerant passages in the condensing heat exchanger is made smaller than the number of refrigerant passages in the outdoor heat exchanger, and the lower part of the outdoor heat exchanger is brought into contact with the upper part of the condensing heat exchanger. desirable.

Further, in the present invention, the condensing heat exchanger is arranged in the front row of the outdoor heat exchanger, so that the outside air heat-exchanged by the condensing heat exchanger flows into the outdoor heat exchanger.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of an air conditioner according to the present invention will be described below with reference to FIGS.
FIG. 1 is a configuration diagram of a refrigeration cycle of an air conditioner according to one embodiment, in which at least one outdoor unit and one indoor unit are connected by a liquid side connection pipe and a gas side connection pipe. The outdoor unit includes a compressor 1, a four-way valve 2, an outdoor heat exchanger 3, an outdoor pressure reducing device 4, a liquid receiver 5, and a condensation heat exchanger 6, and is connected by piping as shown in the figure.
The condensing heat exchanger 6 is provided at the outlet (downstream) side of the receiver 5 during the cooling operation, at the inlet (upstream) side of the receiver 5 during the heating operation, and below the outdoor heat exchanger 3. The number of refrigerant passages in the condensing heat exchanger 6 is made smaller than the number of refrigerant passages in the outdoor heat exchanger 3 so that the lower part of the outdoor heat exchanger 3 and the upper part of the condensing heat exchanger 6 are in contact with each other so that heat can be exchanged. To

The outdoor heat exchanger 3 and the condensing heat exchanger 6
Is equipped with an outdoor fan 9 capable of sending air to the outdoor heat exchanger 3 and the condensation heat exchanger 6 so as to exchange heat with the outside air. Air flows into the exchanger.

On the other hand, the indoor unit includes an indoor heat exchanger 8 and an indoor expansion valve 7 (for example, an electronic expansion valve), and is connected by piping. The indoor heat exchanger 8 is provided with an indoor fan 10 for sending air into the indoor heat exchanger 8 so that heat can be exchanged with the outside air, and air flows into the indoor heat exchanger 8 as indicated by a broken line 12 in the drawing. I do.

In the cooling operation, the condensing heat exchanger 6 exchanges heat of the saturated liquid refrigerant flowing out of the liquid receiver 5 with air to cool the refrigerant in a supercooled liquid state or in a direction in which latent heat of vaporization increases. Has functions. In the heating operation, the air condenses in the indoor heat exchanger 8 and enters a supercooled state.
The refrigerant has a function of turning into a saturated liquid state by exchanging heat with air in a gas-liquid two-phase refrigerant by reducing the pressure.

Next, the operation states of the refrigeration cycle will be described separately for a cooling operation and a heating operation.

(1) Case of Cooling Operation FIG. 2 is a Mollier diagram when the cooling cycle of the refrigeration cycle of the air conditioner according to one embodiment is performed. In the figure, the cycle operating point indicated by the solid line indicates the case of the cycle 14 of the air conditioner in which the condensation heat exchanger 6 is disposed on the outlet (downstream) side of the receiver 5, and is indicated by the broken line. A cycle operating point indicates a cycle 13 of the conventional air conditioner without the condensing heat exchanger 6.

In the cycle 14, the compressor 1 takes the refrigerant in the state of the point a as the high-temperature and high-pressure gas refrigerant at the suction point b.
And flows into the outdoor heat exchanger 3. Driving the outdoor fan 9 exchanges heat with the inflowing outside air and radiates heat to the outside air, and the refrigerant flowing in the outdoor heat exchanger 3 condenses to a supercooled liquid state at point c. Then, the pressure is reduced to the saturated liquid state at the point d by the outdoor decompression device 4 (for example, a capillary tube), flows into the receiver 5, and the excess refrigerant unnecessary for the operation of the refrigeration cycle is stored.

The refrigerant in the saturated liquid state flows out of the receiver 5 and flows into the condensation heat exchanger 6. When the outdoor fan 9 is driven, the refrigerant exchanges heat with the inflowing outside air and radiates heat to the outside air. The refrigerant flowing in the exchanger is condensed to be in a supercooled state at the point e. Then, through the liquid side connection pipe, the indoor expansion valve 7
Is decompressed to the state described above, flows into the indoor heat exchanger 8, drives the indoor fan 10, exchanges heat with the inflowing outside air, absorbs heat from the outside air, and evaporates the refrigerant flowing in the indoor heat exchanger 10. It returns to the state of the point a and returns to the compressor 1.

On the other hand, in the case of cycle 13, points a to d
Up to this point, the same operation as in the cycle 14 is performed, and since the refrigerant in the saturated liquid state at the point d flows out of the receiver 5 and there is no condensation heat exchanger 6, the pressure is reduced by the indoor expansion valve 7 at the point d and the point f ′ Flows into the indoor heat exchanger 8 in the state described above, drives the indoor fan 10 to exchange heat with the inflowing outside air, absorbs heat from the outside air, evaporates the refrigerant flowing in the indoor heat exchanger 10, and evaporates the refrigerant at the point a. It returns to a state and returns to the compressor 1.

When comparing the cooling performance of the present air conditioner with that of the conventional air conditioner, the present embodiment shows that the air conditioner according to the present embodiment has a point f ′ to a point f
It can be seen that the cooling capacity is improved by the latent heat.

(2) Case of Heating Operation FIG. 3 shows a Mollier diagram when the refrigeration cycle of the air conditioner according to one embodiment is operated for heating. In the figure, a cycle operation point indicated by a solid line indicates a case of a cycle 15 of the air conditioner according to one embodiment in which the condensing heat exchanger 6 is disposed on the inlet (upstream) side of the receiver 5. The cycle operation point indicated by the broken line indicates the cycle 16 of the conventional air conditioner without the condensing heat exchanger 6.

In the cycle 15, the compressor 1 takes the refrigerant in the state at the point a as the high-temperature and high-pressure gas refrigerant at the suction point b.
The refrigerant that flows through the gas connection pipe and flows into the indoor heat exchanger 8 and exchanges heat with the inflowing outside air by driving the indoor fan 10 and radiates heat to the outside air. It condenses to a supercooled liquid state at point c. Then, the pressure is reduced to the intermediate pressure in the gas-liquid two-phase state at the point d by the indoor expansion valve 7, flows into the condensing heat exchanger 6 through the liquid connection pipe, and heat is exchanged with the outside air flowing by driving the outdoor fan 9. Then, heat is radiated to the outside air, and the refrigerant flowing in the condensing heat exchanger 6 condenses to a saturated liquid state at a point e, flows into the receiver 5, and stores extra refrigerant not necessary for the operation of the refrigeration cycle. You. The refrigerant in the saturated liquid state flows out of the liquid receiver 5, is decompressed to a point f by the outdoor pressure reducing device 4 (for example, a capillary tube), flows into the outdoor heat exchanger 3, and drives the outdoor fan 9. As a result, the refrigerant flowing in the outdoor heat exchanger 3 evaporates by exchanging heat with the inflowing outside air and absorbing heat from the outside air.
And returns to the compressor 1.

On the other hand, in the case of cycle 16, points a to c
Up to this point, the cycle is the same as in the cycle 15. The supercooled refrigerant at the point c is decompressed by the indoor expansion valve 7 and becomes a saturated liquid state at the point d ', flows into the receiver 5, and is necessary for the operation of the refrigeration cycle. No extra refrigerant is stored. The refrigerant in the saturated liquid state flowing out of the receiver 5 has the same enthalpy as that of the point d 'because the condenser heat exchanger 6 is not provided.
, And flows into the outdoor heat exchanger 3 and the outdoor fan 9
Is driven to exchange heat with the inflowing outside air, absorb heat from the outside air, evaporate the refrigerant flowing in the outdoor heat exchanger 3, and
And returns to the compressor 1.

When comparing the heating performance of the present air conditioner with that of the conventional air conditioner, both air conditioners can heat only the enthalpy difference from the point b to the point c, and the heating performance is equivalent. . However, the indoor expansion valve 7
Since the pressure reduction amount of the outdoor pressure reducing device 4 differs from the pressure at the points d and d ′, the pressure reducing amount of each of the pressure reducing devices differs between the present air conditioner and the conventional air conditioner.

As described above, as shown in FIG. 1, the condensing heat exchanger 6 is arranged at the outlet (downstream) side of the receiver 5 during the cooling operation and at the inlet (upstream) side of the receiver 5 during the heating operation. By adjusting the pressure reduction amounts of the indoor expansion valve 7 and the outdoor pressure reducing device 4, the capacity during the cooling operation can be improved by the amount of heat radiated by the condensation heat exchanger 6. When the compressor 1 is an air conditioner driven by an inverter, the increased heat quantity is used to reduce the drive frequency of the compressor 1, thereby reducing the amount of electric input as compared with the conventional air conditioner. Therefore, a power saving effect can be expected.

Next, the condensing heat exchanger 6 attached to the present air conditioner will be described with reference to FIGS.

FIG. 4 is a perspective view showing a case where the condensation heat exchanger 6 is provided below the outdoor heat exchanger 3. The outdoor heat exchanger 3 includes two rows of a first-row outdoor heat exchanger 20 and a second-row outdoor heat exchanger 21. Each of the outdoor heat exchangers is provided with a plurality of refrigerant pipes through which a refrigerant flows. A plurality of fins for promoting heat exchange performance are attached to the pipe.

Each refrigerant pipe includes a bend pipe and a gas header 2.
2 and the liquid header 23 constitute a plurality of refrigerant passages,
Piping is connected so that the refrigerant flows through each of the refrigerant passages. On the other hand, the condensing heat exchanger 6 is the first row outdoor heat exchanger 2
It is provided below the 0th and 2nd row outdoor heat exchangers 21, and is composed of a plurality of refrigerant pipes and a plurality of fins like each outdoor heat exchanger. The number of refrigerant passages in the condensation heat exchanger 6 is smaller than the number of refrigerant passages in the outdoor heat exchanger. The fins of the condensing heat exchanger 6 are brought into contact with the fins of the first-row outdoor heat exchanger 20 and the second-row outdoor heat exchanger 21 to exchange heat with each fin.

The present air conditioner can exchange heat not only with the air flowing into the condensing heat exchanger 6 but also with the lower part of the outdoor heat exchanger, and has the following effects. That is, in the first-row outdoor heat exchanger 20 and the second-row outdoor heat exchanger 21, a large amount of liquid refrigerant is likely to be present in the lower refrigerant passage due to the influence of gravity, and refrigerant distribution in each refrigerant passage deteriorates. The outdoor heat exchanger cannot be used effectively and the performance is reduced. In the present air conditioner, heat transfer occurs due to contact between the fins of the condensation heat exchanger 6 and the lower fins of the outdoor heat exchanger, and in the heating operation, a part of the condensation heat from the condensation heat exchanger 6 is generated. Since the lower part of each outdoor heat exchanger absorbs heat, the refrigerant can be completely evaporated even if the length of the refrigerant pipe in the lower refrigerant passage is short. on the other hand,
In the case of the cooling operation, in each of the outdoor heat exchangers, the amount of the liquid refrigerant generated in each lower part of the outdoor heat exchanger can be reduced by shortening the length of the refrigerant pipe of the lower refrigerant passage. Therefore, deterioration of refrigerant distribution can be prevented, and each outdoor heat exchanger can be used effectively.

FIG. 5 is a perspective view showing an embodiment in which the condensing heat exchanger 6 is provided below the outdoor heat exchanger 3.
In the drawing, the same reference numerals as those in FIG. 4 indicate the same components. The outdoor heat exchanger 3 has the same configuration as that shown in FIG.
The condensation heat exchanger 6 includes a first-row outdoor heat exchanger 20 and a second-row outdoor heat exchanger 20.
It has a plurality of refrigerant pipes and a plurality of fins by using a part of the lower part of the row outdoor heat exchanger 21, and makes the number of refrigerant passages of the condensation heat exchanger 6 smaller than the number of refrigerant passages of the outdoor heat exchanger 3. ing.

In the present air conditioner, since the fins of the outdoor heat exchanger and the fins of the condensation heat exchanger 6 are integrally formed, the following effects are obtained. That is, since the heat generated from the condensation heat exchanger 6 is transmitted to the lower part of each outdoor heat exchanger by heat conduction of the fins, the heat can be further transmitted to the outdoor heat exchanger. This prevents the outdoor heat exchanger from exhibiting its original performance. Further, since the condensing heat exchanger 6 is formed integrally with the outdoor heat exchanger, the manufacturing cost can be reduced.

Next, an air conditioner according to still another embodiment will be described with reference to FIGS.

FIG. 6 is a configuration diagram of a refrigeration cycle of an air conditioner having a condensing heat exchanger 6 according to another embodiment. The condensation heat exchanger 6 is arranged on the inlet side of the air flowing into the outdoor heat exchanger 3 so as to cover the front surface of the outdoor heat exchanger 3.

FIG. 7 is a perspective view showing still another embodiment. The condensing heat exchanger 6 includes a plurality of refrigerant pipes and a plurality of fins on the inlet side of the air flowing into the first-row outdoor heat exchanger 20 and the second-row outdoor heat exchanger 21.
It is arranged so as to cover the front surface of the row outdoor heat exchanger 20. Further, an air layer is provided between the first-row outdoor heat exchanger 20 and the condensation heat exchanger 6, and the air prevents heat transfer to the first-row outdoor heat exchanger 20.

Next, changes in the temperature of the air flowing into the condensing heat exchanger 6 and the outdoor heat exchanger in the above-described embodiment will be described for a cooling operation and a heating operation.

(1) Cooling Operation FIG. 8 shows the temperature change of the air flowing into the condensing heat exchanger 6, the first-row outdoor heat exchanger 20, and the second-row outdoor heat exchanger 21 during the cooling operation. FIG. The solid line indicates the temperature change 30 of the inflow air when the condensing heat exchanger 6 of the present invention is provided on the front row side with respect to the air flowing into the first-row outdoor heat exchanger 20, Shows a temperature change 31 of the inflow air when the condensing heat exchanger 6 is not provided.
Assuming that the outside air temperature is T1, the temperature change of the inflow air when the conventional condensing heat exchanger 6 is not provided is that the refrigerant exchanges heat with the inflow air in the first-row outdoor heat exchanger 20 to condense the refrigerant. Then, the heat is released to the air and rises to T5 at the entrance of the second-row outdoor heat exchanger 21. The second row outdoor heat exchanger 21 further exchanges heat to condense the refrigerant and radiate heat to the air.
To rise.

On the other hand, when the condensing heat exchanger 6 is provided, the change in temperature of the inflowing air is caused by the heat exchange with the inflowing air in the condensing heat exchanger 6 and supercooling of the refrigerant to radiate heat to the air. At the entrance of the outdoor heat exchanger 20, the temperature rises to T2 (> T1).
Next, the refrigerant exchanges heat with the inflow air in the first-row outdoor heat exchanger 20 to radiate heat to the air, and rises to T3 (> T5) at the entrance of the second-row outdoor heat exchanger 21. I do. Then, the second row outdoor heat exchanger 21 further exchanges heat to condense the refrigerant, thereby radiating heat to air and rising to T4 (> T6).

As described above, when the condensing heat exchanger 6 is provided, the temperature of the air blown out from the outdoor heat exchanger becomes higher than in the conventional case, so that more heat can be radiated. The cooling capacity is improved.

(2) In the case of heating operation FIG. 9 shows the temperature change of the air flowing into the condensing heat exchanger 6, the first-row outdoor heat exchanger 20 and the second-row outdoor heat exchanger 21 during the heating operation. FIG. The solid line indicates the temperature change 32 of the inflow air when the condensing heat exchanger 6 of the present invention is provided on the front row side with respect to the air flowing into the first row outdoor heat exchanger 20. Shows a temperature change 33 of the inflow air when the condensing heat exchanger is not provided. Assuming that the outside air temperature is T1, the temperature change of the inflow air when the conventional condensing heat exchanger 6 is not provided is that the refrigerant is evaporated by exchanging heat with the inflow air in the first row outdoor heat exchanger 20. At the entrance of the second-row outdoor heat exchanger 21 to T5. The second row outdoor heat exchanger 21 further exchanges heat to evaporate the refrigerant, thereby absorbing heat from the air, and
It drops to 6.

On the other hand, when the condensing heat exchanger 6 is provided, the change in temperature of the inflowing air is caused by the heat exchange with the inflowing air in the condensing heat exchanger 6 and supercooling of the refrigerant to radiate heat to the air. At the entrance of the outdoor heat exchanger 20, the temperature rises to T2 (> T1).
Next, the refrigerant exchanges heat with the inflow air in the first-row outdoor heat exchanger 20 to evaporate the refrigerant, thereby absorbing heat from the air and decreasing to T3 (> T5) at the entrance of the second-row outdoor heat exchanger 21. I do. The second row outdoor heat exchanger 21 further exchanges heat to evaporate the refrigerant, thereby absorbing heat from the air and lowering the temperature to T4 (> T6).

As described above, when the condensing heat exchanger 6 is provided, the temperature of the air flowing into the first-row outdoor heat exchanger 20 by the condensing heat exchanger 6 is T2> as compared with the conventional case.
It becomes T1. That is, when the outside air is low in the conventional case, the temperature of the outdoor heat exchanger 3 acting as an evaporator becomes 0 ° C. or less, and frost adheres to the fins and the like, deteriorating the performance of the outdoor heat exchanger 3. Not only that, frost formation progresses, and the heating capacity cannot be sufficiently exhibited. Therefore, the defrosting operation had to be performed, but in this example, the temperature of the air sucked into the outdoor heat exchanger 3 by the condensing heat exchanger 6 increases, and the degree of frost adhering to the outdoor heat exchanger 3 is reduced. Decreases or frost stops depending on the outside temperature,
The heating capacity when the outside air is low can be improved.

Here, as a method of setting the number of refrigerant passages in the condensing heat exchanger 6, the pressure loss is increased so that the outlet of the condensing heat exchanger 6 becomes a saturated liquid state or a gas-liquid two-phase state. In the case where the speed of the refrigerant passing through the condensing heat exchanger 6 is increased, the condensing heat transfer rate on the refrigerant side is improved and the amount of heat radiation is increased, and the amount of the refrigerant in the condensing heat exchanger 6 is also supercooled. Less compared to. For this reason, the amount of the refrigerant to be sealed in the air conditioner is reduced, so that the performance of the air conditioner can be improved and the manufacturing cost can be reduced.

[0044]

As described above, according to the present invention,
The condensing heat exchanger is located at the outlet side of the receiver during cooling operation and at the inlet side of the receiver during heating operation, so the condensing heat exchanger is effectively used for both cooling and heating operations it can.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a refrigeration cycle in which a condensation heat exchanger is provided below an outdoor heat exchanger in an air conditioner according to one embodiment.

FIG. 2 is a Mollier chart showing a cooling operation state of a refrigeration cycle in the air conditioner according to one embodiment and a conventional air conditioner.

FIG. 3 is a Mollier chart showing a heating operation state of a refrigeration cycle in the air conditioner according to the embodiment and a conventional air conditioner.

FIG. 4 is a perspective view showing a state in which a condensation heat exchanger is provided below the outdoor heat exchanger according to one embodiment.

FIG. 5 is a perspective view showing a state in which a condensation heat exchanger is provided below an outdoor heat exchanger according to another embodiment.

FIG. 6 is a configuration diagram of a refrigeration cycle according to one embodiment.

FIG. 7 is a perspective view showing a state in which a condensing heat exchanger according to another embodiment is provided.

FIG. 8 is a diagram showing a temperature change of air flowing into a condensing heat exchanger and an outdoor heat exchanger during a cooling operation.

FIG. 9 is a diagram showing a temperature change of air flowing into a condensing heat exchanger and an outdoor heat exchanger during a heating operation.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Compressor, 2 ... 4-way valve, 3 ... Outdoor heat exchanger, 4 ... Outdoor decompression device, 5 ... Liquid receiver, 6 ... Condensation heat exchanger, 7 ... Indoor expansion valve, 8 ... Indoor heat exchanger, 9 ... outdoor fan, 10 ... indoor fan, 11 ... outdoor inflow air, 12 ... indoor inflow air, 1
3 ... Conventional cooling cycle, 14 ... Cooling cycle with condensing heat exchanger, 15 ... Heating cycle with condensing heat exchanger, 20 ... First row outdoor heat exchanger, 21 ... Second row outdoor heat Exchanger, 22 gas header, 23 ... liquid header, 30
······················································································································································································ Change, 33: change in outdoor air temperature during conventional heating operation.

Continued on the front page (72) Inventor Atsuhiko Yokoseki 390 Muramatsu, Shimizu-shi, Shizuoka Pref.Hitachi Air Conditioning System Shimizu Production Headquarters Co., Ltd. F term (reference) 3L092 AA01 BA16

Claims (5)

[Claims] 1. An air conditioner in which a compressor, an indoor heat exchanger, a decompression device, a liquid receiver, and an outdoor heat exchanger are connected to a pipe, and in a cooling operation, a heating operation is performed on an outlet side of the liquid receiver. An air conditioner, comprising: a condensing heat exchanger disposed at an inlet side of the liquid receiver at the time, and allowing the condensing heat exchanger to exchange heat with a lower portion of the outdoor heat exchanger. . 2. The air conditioner according to claim 1, wherein a lower part of the outdoor heat exchanger is used as the condensation heat exchanger. 3. The condensing heat exchanger according to claim 1, wherein the number of refrigerant passages in said condensation heat exchanger is smaller than the number of refrigerant passages in said outdoor heat exchanger. An air conditioner characterized by contacting the upper part of the vessel. 4. A condenser, an indoor heat exchanger, a pressure reducing device, a liquid receiver, and an outdoor heat exchanger are connected by piping, and the condensing heat exchanger is operated so as to function as a condenser during both the cooling operation and the heating operation. In the disposed air conditioner, the condensation heat exchanger is disposed in a front row of the outdoor heat exchanger,
An air conditioner, wherein outside air heat-exchanged by the condensation heat exchanger flows into the outdoor heat exchanger. 5. The air conditioner according to claim 1, wherein the compressor is driven by an inverter.