JP2001317831A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioner in which dehumidifying operation is achieved, and performance of cooling operation and heating operation are kept satisfactorily higher, and further reliability in dehumidification is improved. SOLUTION: A first indoor heat exchanger 6 is provided on the side of indoor air intake by an indoor fan 8 and a second indoor heat exchanger 7 disposed upstream of the former, and a dehumidifying throttling apparatus 10 is provided therebetween in an indoor unit 1. There is provided a dehumidifying four-way valve 16 connected to an outdoor four-way valve of an outdoor unit, an outdoor heat exchanger, and first and second indoor heat exchangers 6, 7 for forcing a refrigerant to pass from the first indoor heat exchanger 6 to the second indoor heat exchanger 7 upon heating operation and dehumidifying operation, and for forcing the refrigerant to pass from the second indoor heat exchanger 7 to the first indoor heat exchanger 6 upon cooling operation, for the dehumidifying throttling device 10 it is controlled to demonstrate a throttling function only upon the dehumidifying operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner which can be operated in cooling, heating and dehumidifying modes.

[0002]

2. Description of the Related Art A conventional air conditioner is disclosed in JP-A-7-139848, JP-A-10-246506, and JP-A-3-3, as examples of a refrigeration cycle in which air cooled during a dehumidifying operation is heated again by the refrigeration cycle itself. There is one described in JP-A-31640.

As shown in FIG. 7, Japanese Patent Application Laid-Open No. 7-139848 includes at least a compressor 51, indoor heat exchangers 52 and 53, expansion devices 54 and 58, and an outdoor heat exchanger 55. Air conditioner, the indoor heat exchanger 5
2 and 53 have a cooling / dehumidifying portion and a heating portion, and control the fan air volume of the outdoor heat exchanger 55, the capacity of the compressor 51, and the fan air volume of the indoor heat exchangers 52 and 53 during the dehumidifying operation. To control the heating capacity of the heating portion and the amount of heat radiated from the outdoor heat exchanger 55, as shown in FIG.
It is disclosed that a bypass pipe 57 provided with is provided to perform a dehumidifying operation for heating by controlling the two-way valve 56 to be opened during the dehumidifying operation, and the efficiency of the heat exchanger is also disclosed. In order to raise the flow rate, some optimal piping configurations that make the flow countercurrent as much as possible are also mentioned.

In Japanese Patent Laid-Open Publication No. Hei 10-246506, as shown in FIG.
2, an after-cooling fan 63, and an indoor unit for an air conditioner in which an indoor heat exchanger 64 is arranged between the suction ports 61 and 62 and the once-through fan 63, the indoor heat exchanger 64 has an upper surface. The indoor heat exchanger 6 includes an upper surface side heat exchange unit 65 arranged facing the suction port 61 and a front side heat exchange unit 66 arranged facing the front surface suction port 62.
It is disclosed that the upper surface side heat exchange unit 65 and the front surface heat exchange unit 66 of 4 are thermally separated from each other.

In Japanese Patent Application Laid-Open No. 3-31640, FIG.
As shown in at least, the compressor 71, the four-way valve 72,
The expansion device 73, the outdoor heat exchanger 74, a first indoor heat exchanger 75 provided on the indoor air suction side, and a second indoor heat exchanger 75 provided on the indoor air suction side connected in series with the first indoor heat exchanger 75. And an air conditioner configured by connecting an indoor heat exchanger 76 and an indoor unit 78 including a flow control throttling device 77 provided between the first and second indoor heat exchangers 75 and 76. , Four-way valve 72, outdoor heat exchanger 74, first,
A flow path switching unit 79 connected to each of the second indoor heat exchangers 75 and 76 and constantly flowing the refrigerant from the first indoor heat exchanger 75 to the second indoor heat exchanger 76 regardless of the operation mode is provided. The provided configuration is disclosed.

[0006]

However, in the configuration disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 10-246506,
At the time of the dehumidifying operation, the cooling, dehumidifying unit and the heating unit are constituted by the two heat exchange units 65 and 66 arranged vertically in the indoor heat exchanger. There is a risk that the warm air mixes and dew condensation is likely to occur in the once-through fan 63. In addition, during cooling or heating, there are many places where the flow of the refrigerant and the flow of the air are parallel to each other. Efficiency may be reduced.

Further, in the configuration disclosed in Japanese Patent Application Laid-Open No. 3-31640, there are many places where the flow of the refrigerant and the flow of the air are parallel to each other in either the cooling mode or the heating mode. The efficiency of the vessel may be reduced.

In the structure disclosed in Japanese Patent Application Laid-Open No. 7-139848, a bypass pipe 57 having a two-way valve 56 is provided.
Is located at the outlet of the four-way valve 59 and the inlet of the main expansion device (expansion valve) 54, so that part of the high-temperature gas discharged from the compressor 51 during the dehumidifying operation passes through the outdoor heat exchanger 55 and is heat exchanged. There is a risk that the gas will merge with the low-temperature gas, making the warm dehumidifying operation difficult. In addition, even if a cutting line is provided in the piping configuration (path configuration) or the fins so that the flow becomes as opposed as possible during the cooling / heating operation, the flow of the refrigerant may be on the windward side with respect to the flow of the air during the operation, If it is on the side, heat exchange loss will occur, and the efficiency may be reduced.

SUMMARY OF THE INVENTION The present invention is to solve such a conventional problem. First, it is an object of the present invention to provide an air conditioner capable of maintaining a sufficiently high performance in a cooling operation or a heating operation while performing a dehumidifying operation. Secondly, it is an object of the present invention to provide an air conditioner with improved reliability in dehumidification, and thirdly, to provide an air conditioner capable of performing a dehumidification operation for various uses.

[0010]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is directed to an outdoor unit having a compressor, an outdoor four-way valve, an outdoor expansion device, an outdoor heat exchanger, an outdoor fan, and an indoor unit. A first indoor heat exchanger provided on the indoor air suction side by the fan, which is connected in series with the first indoor heat exchanger, and is disposed on the windward side of the first indoor heat exchanger on the indoor air suction side. An air conditioner configured by connecting a second indoor heat exchanger and an indoor unit having a dehumidifying expansion device provided between the first and second indoor heat exchangers, wherein the outdoor four-way Valve, outdoor heat exchanger, first,
Connected to each of the second indoor heat exchangers, the refrigerant flows from the first indoor heat exchanger to the second indoor heat exchanger during the heating operation and the dehumidifying operation, and the second indoor heat exchange during the cooling operation. Flow path switching means for flowing the refrigerant from the heat exchanger to the first indoor heat exchanger, an outdoor four-way valve, an outdoor throttle device, a flow path switching means, and a dehumidifying throttle device, and a dehumidifying operation is performed for the dehumidifying throttle device. Control means for controlling the aperture function to be exerted only at the time.

In this configuration, during the dehumidifying operation, the first indoor heat exchanger on the leeward side functions as a condenser by exerting the throttling function of the dehumidifying expansion device, and the second indoor heat exchanger on the leeward side. The vessel functions as an evaporator. Therefore, the air introduced into the indoor unit is first dehumidified by the second indoor heat exchanger, and thereafter, is warmed by the first indoor heat exchanger. Comfortable dehumidifying performance can be obtained. Also,
At the time of cooling operation, by making both indoor heat exchangers function as evaporators, the refrigerant flows from the second indoor heat exchanger on the leeward side to the first indoor heat exchanger on the leeward side. The flow of the refrigerant is always countercurrent to the flow in terms of temperature. During the heating operation, by making both indoor heat exchangers function as condensers, the refrigerant flows from the first indoor heat exchanger on the leeward side to the second indoor heat exchanger on the leeward side,
The flow of the refrigerant is always countercurrent to the flow of air in terms of temperature. As described above, during the cooling operation and the heating operation, the flow of the refrigerant and the flow of the room air can be made to be countercurrent in terms of temperature, so that the heat exchange efficiency can be improved.

According to a second aspect of the present invention, in the air conditioner of the first aspect, the control means detects the indoor temperature and the set temperature to control the switching of the outdoor four-way valve and the rotation speed of the outdoor fan. It is.

With this configuration, by detecting the indoor temperature and the set temperature, switching the outdoor four-way valve and controlling the outdoor fan speed, the cooling operation, the heating operation, and the dehumidifying operation can be performed in a favorable state suitable for the temperature. Can be done with

According to a third aspect of the present invention, in the air conditioner according to the first or second aspect, a four-way valve is used as a flow path switching unit. With this configuration, the flow paths can be favorably switched with a relatively simple configuration.

According to a fourth aspect of the present invention, in the air conditioner of the third aspect, the four-way valve used as the flow path switching means is controlled so as to be energized and switched only during the dehumidifying operation.

With this configuration, it is not necessary to supply power during the cooling operation or the heating operation, so that the operation cost can be reduced. According to a fifth aspect of the present invention, there is provided an air conditioner including a compressor, an indoor heat exchanger, a four-way valve, an outdoor expansion device, and an outdoor heat exchanger, wherein the indoor heat exchanger includes an indoor air suction side leeward portion. A first indoor heat exchanger that is disposed in the room and serves as a heating unit during the dehumidifying operation; a second indoor heat exchanger that is disposed at the indoor air suction side windward and serves as a cooling / dehumidifying unit during the dehumidifying operation; A dehumidifying throttle device disposed between the second indoor heat exchangers; and a pipe for bypassing an inlet of the outdoor throttle device and the compressor suction side in a dehumidifying mode of the same cycle as the heating cycle. A two-way valve is provided in the pipe, and the refrigerant is circulated from the first indoor heat exchanger to the second indoor heat exchanger by controlling the outdoor throttle device to be closed and the two-way valve to be open during the dehumidifying operation. ,
During the heating operation, the four-way valve is switched so that the refrigerant flows from the first indoor heat exchanger to the second indoor heat exchanger. During the cooling operation, the refrigerant flows from the second indoor heat exchanger to the first indoor heat exchanger. And a control means for switching the four-way valve so that the gas flows.

According to a sixth aspect of the present invention, there is provided an air conditioner including a compressor, an indoor heat exchanger, a four-way valve, an outdoor expansion device, and an outdoor heat exchanger. A first indoor heat exchanger disposed at a side leeward location and serving as a heating unit during a dehumidification operation, and a second indoor heat exchanger disposed at an indoor air suction side leeward portion and serving as a cooling / dehumidification unit during a dehumidification operation, A first and second indoor heat exchanger provided with a dehumidifying throttle device, and a pipe that bypasses the outdoor throttle device outlet and the four-way valve high-pressure outlet in the dehumidifying mode of the same cycle as the cooling cycle; The bypass pipe is provided with a two-way valve, and during the dehumidifying operation, the outdoor throttle device is closed and the two-way valve is controlled to open, so that the refrigerant is transferred from the first indoor heat exchanger to the second indoor heat exchanger. Distributed to
During the heating operation, the four-way valve is switched so that the refrigerant flows from the first indoor heat exchanger to the second indoor heat exchanger. During the cooling operation, the refrigerant flows from the second indoor heat exchanger to the first indoor heat exchanger. And a control means for switching the four-way valve so that the gas flows.

According to the fifth and sixth aspects of the invention, the air introduced into the indoor unit during the dehumidifying operation is first dehumidified by the second indoor heat exchanger, and thereafter, by the first indoor heat exchanger. It is warmed, and it becomes possible to perform warm dehumidification from the same temperature as a dehumidifier, so that comfortable dehumidification performance can be obtained. Also, at the time of cooling operation, by making both indoor heat exchangers function as evaporators, the refrigerant flows from the second indoor heat exchanger on the windward side to the first indoor heat exchanger on the leeward side, The flow of the refrigerant is always countercurrent to the flow of air in terms of temperature. During the heating operation, by making both indoor heat exchangers function as condensers, the refrigerant flows from the first indoor heat exchanger on the leeward side to the second indoor heat exchanger on the leeward side. The flow of the refrigerant is always countercurrent to the flow in terms of temperature. As described above, during the cooling operation and the heating operation, the flow of the refrigerant and the flow of the room air can be made to be countercurrent in terms of temperature, so that the heat exchange efficiency can be improved.

According to a seventh aspect of the present invention, in the air conditioner according to any one of the first to sixth aspects, the outdoor expansion device is an electric expansion valve that can be fully closed and fully opened. The present invention according to claim 8 is the air conditioner according to any one of claims 1 to 7, wherein the dehumidifying throttle device is an electric expansion valve that can be adjusted between a predetermined throttle state and a fully closed state. is there.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. (Embodiment 1) FIG. 1 is a diagram showing a refrigeration cycle configuration of an air conditioner during a dehumidifying operation according to an embodiment of the present invention. FIG. 2 shows a refrigeration cycle during a cooling operation, and FIG. Is shown. FIG. 4 illustrates an example in which a four-way valve serving as a flow path switching unit is housed in an indoor unit.

As shown in FIG. 1, in this air conditioner, an indoor unit 1 and an outdoor unit 2 are connected at a location of a two-way valve 4 and a three-way valve 5 which are connecting portions of a piping unit 3. I have.

The indoor unit 1 includes an indoor once-through fan 8,
First indoor heat exchanger 6 provided on the indoor air suction side
And the first indoor heat exchanger 6 on the indoor air suction side
And a second indoor heat exchanger 7 disposed further upstream in the windward direction. In addition, a dehumidifying throttle device 10 is provided in the middle of a heat exchanger connecting pipe 9 for connecting the first indoor heat exchanger 6 and the second indoor heat exchanger 7, and the dehumidifying throttle is provided. A two-way valve 11 for flowing a refrigerant during cooling / heating operation is provided in parallel with the device 10.

The outdoor unit 2 includes a compressor 12, an outdoor fan 13, and an outdoor heat exchanger 19. The compressor 12 is capable of controlling the capacity, and the outdoor fan 13 and the indoor flow-through fan 8 are also capable of controlling the capacity, that is, controlling the air volume. Is configured to be possible. Further, in addition to an expansion valve 14 as an outdoor expansion device and a four-way valve 15 for switching the flow direction of the refrigerant between cooling and heating, a four-way valve 16 as flow switching means for connecting to the indoor unit 1 is provided. The four-way valve 16 for switching the passage allows the refrigerant to flow from the first indoor heat exchanger 6 to the second indoor heat exchanger 7 during the heating operation (see FIG. 3) and the dehumidifying operation (see FIG. 1). During the cooling operation (see FIG. 2), the operation is switched so that the refrigerant flows from the second indoor heat exchanger 7 to the first indoor heat exchanger 6. Note that arrows 17, 1 in FIGS.
Numeral 8 indicates the outdoor and indoor wind directions, respectively. Also, the four-way valve 16 for switching the flow path may be disposed on the outdoor unit 2 side as shown in FIGS.
It may be arranged on the side or in any case.

Two-way valve 11, four-way valves 15, 16, expansion valve 1
The switching control operation or the flow rate control operation of Step 4 and the rotation control operation of the indoor once-through fan 8 and the outdoor fan 13 are performed by a control unit (not shown), and a two-way valve that connects the indoor unit 1 and the outdoor unit 2 4 and the three-way valve 5 are normally open and communicate with each other at a location shown in the figure.

In the above-described cycle configuration, during the dehumidifying operation, the two-way valve 11 provided in parallel with the dehumidifying throttle device 10 is closed, while the expansion valve 14 is fully opened. The four-way valves 15 and 16 are connected in the direction shown by the solid line in FIG.

In the dehumidifying operation, as shown in FIG. 1, the high-temperature and high-pressure refrigerant gas pressurized by the compressor 12 is radiated to the outside when passing through the outdoor heat exchanger 19, and then is fully opened. The flow path is switched by the four-way valve 16 for switching the flow path without being decompressed through 14, and flows into the first indoor heat exchanger 6 (functioning as a condenser) through the three-way valve 5 which is a connecting portion. Then, the heat is radiated again. Thereafter, the pressure is reduced by the indoor expansion device 10, and then flows into the second indoor heat exchanger 7 (functioning as an evaporator), where the indoor air 18 is cooled and dehumidified. Thereafter, the low-temperature low-pressure refrigerant gas passes through the two-way valve 4, which is another connection part, passes through the four-way valve 16 for switching the flow path, and returns to the compressor 12. At this time, in the indoor heat exchangers 6 and 7, since the cooling / dehumidifying portion is always provided on the windward side of the heated portion, all the dehumidified low-temperature air is heated again, and thereby the isothermal temperature is equal to that of the dehumidifier. Warm dehumidification becomes possible, and comfortable dehumidification performance can be obtained. The heating-side capacity is the outdoor fan 13 and the compressor 1
2 can be controlled. Furthermore, since the low-temperature air and the high-temperature air do not mix, the indoor fan 8 does not condense.

At the time of the cooling operation, as shown in FIG. 2, the outdoor side has a normal cooling cycle, and the gaseous refrigerant decompressed by the expansion valve 14 passes through the two-way valve 4 which is a connecting portion. The four-way valve 16 for switching the flow path is switched, and the two-way valve 11 provided in parallel with the dehumidifying throttle device 10 is opened. In the indoor unit 1, the refrigerant first absorbs heat in the second indoor heat exchanger 7 (functioning as an evaporator) on the windward side, and then passes through the two-way valve 11 having low pressure loss and low heat loss. Heat is absorbed by the first indoor heat exchanger 6 (functioning as an evaporator) on the side, and thus the entire indoor heat exchangers 6 and 7 are used as an evaporator. At this time, the temperature of the refrigerant is lower in the first indoor heat exchanger 6 than in the second indoor heat exchanger 7,
The flow 18 of the room air always flows countercurrently with respect to the flow of the refrigerant. As a result, the overall heat efficiency of the indoor heat exchangers 6, 7 is increased.

Next, as shown in FIG. 3, during the heating operation, the outdoor side is set to the normal heating cycle, and the gaseous refrigerant pressurized by the compressor 12 passes through the three-way valve 5 which is the connection part. The four-way valve 16 for switching the flow path is switched, and the two-way valve 11 provided in parallel with the dehumidifying throttle device 10 is opened. In the indoor unit 1, the refrigerant first radiates heat when passing through the first indoor heat exchanger 6 (functioning as a condenser) on the leeward side, and then passes through the two-way valve 11 having low pressure loss and low heat loss. After that, the second indoor heat exchanger 7 on the windward side
(Functions as a condenser) to release heat, and thus the entire indoor heat exchangers 6 and 7 are used as a condenser. At this time, the flow 18 of the indoor air always flows in a direction opposite to the flow of the refrigerant in terms of temperature. As a result, the overall heat efficiency of the indoor heat exchangers 6 and 7 increases.

If the four-way valve 16 for switching the flow path is controlled so that an electric input is applied only during the dehumidifying operation, the power consumption in the normal heating operation and cooling operation can be reduced. (Embodiment 2) FIG. 5 shows a configuration of a refrigeration cycle of an air conditioner during a dehumidifying operation according to another embodiment of the present invention. Although the configuration of the indoor unit 1 and the flow of the refrigerant are the same as those in the first embodiment, the outdoor unit 2 includes a bypass pipe 21 that bypasses the inlet of the expansion valve 14 as an outdoor expansion device and the compressor 12 suction. The bypass pipe 21 is provided with a two-way valve 20 for dehumidification.

During the dehumidifying operation, the four-way valve 15 of the outdoor unit 2 is switched in the same direction as in the heating cycle, as shown in the figure, to completely close the expansion valve 14, which is an outdoor throttle device, and to perform dehumidification. By opening the two-way valve 20,
The refrigerant gas discharged from the compressor 12 passes through the three-way valve 5 as a connection portion, flows into the first indoor heat exchanger 6 on the leeward side, radiates heat, and is then depressurized by the dehumidifying throttle device 10, Next, it flows into the second indoor heat exchanger 7 on the windward side and absorbs heat. After that, it passes through the two-way valve 4 which is the other connection part, and returns to the outdoor unit 2. However, since the expansion valve 14 is completely closed, the bypass pipe 21 is not passed through the outdoor heat exchanger 19 but passes through. And returns to the compressor 12. At this time, dehumidification in the indoor unit 1 is performed in the same manner as in the first embodiment,
Similar effects can be obtained. In addition, warmer dehumidification can be achieved because there is no heat radiation in the outdoor heat exchanger 19. Further, since the inexpensive two-way valve 20 is used without using the flow path switching four-way valve 16, it is more advantageous in cost than the first embodiment.

During the heating operation and the cooling operation, the dehumidifying two-way valve 20 is closed and the operation is returned to the normal refrigeration cycle, and the indoor unit 1 forms a cycle similar to that of the first embodiment. The efficiency of the heat exchangers 6 and 7 can be maintained high as in the first embodiment. (Embodiment 3) FIG. 6 shows a configuration of a refrigeration cycle of an air conditioner during a dehumidifying operation according to another embodiment of the present invention. In this air conditioner, the outdoor unit 2 is provided with an expansion valve 1 as an outdoor throttle device.
A bypass pipe 23 is provided for bypassing the outlet 4 and the high-pressure outlet of the four-way valve 15 of the outdoor unit 2, and a two-way valve 22 for dehumidification is provided in the bypass pipe 23.

During the dehumidifying operation, the four-way valve 15 is switched in the same direction as in the cooling cycle as shown in FIG.
By completely closing the expansion valve 14 as the outdoor throttle device and opening the two-way valve 22 for dehumidification, the refrigerant gas discharged from the compressor 12 passes from the vise pipe 23 through the two-way valve 4 as a connection. Then, enter the indoor unit 1. Thereafter, it flows into the first indoor heat exchanger 6 on the leeward side, radiates heat, and is then depressurized by the dehumidifying throttle device 10, and then the second on the leeward side.
It flows into the indoor heat exchanger 7 and absorbs heat. Then, it passes through the three-way valve 5 which is the other connection part, and returns to the compressor 12 in the outdoor unit 2. At this time, dehumidification in the indoor unit 1 is performed in the same manner as in the first embodiment, and a similar effect is obtained.
In addition, warmer dehumidification can be performed at a higher temperature because there is no heat radiation in the outdoor heat exchanger 19, and if it is desired to return to cooler dehumidification, the dehumidification two-way valve 22 is closed and the expansion valve 14 is opened. Can be controlled relatively easily. Further, since the inexpensive two-way valve 22 is used without using the flow path switching four-way valve 16, the cost is more advantageous than in the first embodiment.

In the above embodiment, the case where the two-way valve 11 for flowing the cooling / heating refrigerant in parallel with the dehumidifying expansion device 10 is provided between the indoor heat exchangers 6 and 7 has been described. However, the present invention is not limited to this, and the two-way valve 11 may be omitted by using a dehumidifying throttle device 10 that can adjust the opening degree between a predetermined throttle state and a fully open state, and in this case, the components may be omitted. Since the number of points is reduced, storability is improved.

[0034]

As is apparent from the above embodiment, according to the first aspect of the present invention, the first indoor heat exchanger is provided on the leeward side of the indoor air suction side, and the second indoor heat exchanger is provided on the leeward side.
Are provided, and a dehumidifying throttle device is provided between them. The refrigerant is transferred from the first indoor heat exchanger to the second indoor heat exchanger during the heating operation and the dehumidifying operation by the flow path switching means. During cooling operation, the first indoor heat exchanger
By circulating the refrigerant to the indoor heat exchanger of the dehumidifying throttle device, by exerting the throttle function only during the dehumidifying operation,
During the dehumidifying operation, the cooling / dehumidifying part is always upwind from the heated part, and all the low-temperature dehumidified air is heated again, so that it is possible to dehumidify from the same temperature as the dehumidifier and warm dehumidification, and obtain comfortable dehumidifying performance. be able to. Moreover, at the time of the cooling operation and the heating operation, the flow of the refrigerant and the flow of the indoor air can be made into countercurrent flows in terms of temperature, so that the heat exchange efficiency can be improved. Further, since the low-temperature air and the high-temperature air do not mix, there is no condensation on the fan.

Further, by detecting the indoor temperature and the set temperature, switching the outdoor four-way valve and controlling the outdoor fan speed, the cooling operation, the heating operation and the dehumidifying operation are performed in a favorable state suitable for the temperature. be able to.

Further, by using a four-way valve as a flow path switching means which can be switched by energizing only during the dehumidifying operation,
Power consumption during cooling operation and heating operation can be reduced, and operation costs can be reduced.

A first indoor heat exchanger which is disposed on the leeward side of the indoor air suction side and serves as a heating unit during the dehumidifying operation;
A second indoor heat exchanger, which is disposed at the windward side on the indoor air suction side and serves as a cooling / dehumidifying unit during a dehumidifying operation, and a dehumidifying throttle device disposed between the first and second indoor heat exchangers are provided. ,
A bypass pipe provided with a two-way valve is provided, and during the dehumidifying operation, the outdoor expansion device is closed and the two-way valve is opened to control the refrigerant from the first indoor heat exchanger to the second indoor heat exchange. To switch the refrigerant from the first indoor heat exchanger to the second indoor heat exchanger during the heating operation,
During the cooling operation, by switching the refrigerant from the second indoor heat exchanger to the first indoor heat exchanger, more warm dehumidification becomes possible, and a comfortable dehumidification performance can be obtained. During the cooling operation and the heating operation, the flow of the refrigerant and the flow of the indoor air can be made countercurrent in terms of temperature, so that the heat exchange efficiency can be improved,
There is no fan condensation since low-temperature air and high-temperature air do not mix. Further, since an inexpensive two-way valve is used, manufacturing costs can be reduced.

Further, by using a motor-operated expansion valve which can be fully closed and fully opened as the outdoor expansion device, thermal leakage can be reduced, so that the temperature of the indoor heating section can be further increased and the room can be warmer. Dehumidification control becomes possible.

Further, by using an electric expansion valve that can be adjusted between a predetermined throttle state and a fully closed state as a dehumidifying throttle device, it is not necessary to provide a two-way valve in parallel, so that the number of parts is reduced. It is reduced and storage is improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a refrigeration cycle in an air conditioner according to an embodiment of the present invention, showing a case of a dehumidifying operation.

FIG. 2 is a diagram showing a configuration of a refrigeration cycle in the air conditioner, showing a case of a cooling operation.

FIG. 3 is a diagram showing a configuration of a refrigeration cycle in the air conditioner, showing a case of a heating operation.

FIG. 4 is a diagram showing a configuration of a refrigeration cycle of the air conditioner in which a four-way valve serving as a flow path switching unit is housed in an indoor unit.

FIG. 5 is a diagram illustrating a configuration of a refrigeration cycle of an air conditioner during a dehumidifying operation according to another embodiment of the present invention.

FIG. 6 is a diagram illustrating a configuration of a refrigeration cycle of an air conditioner during a dehumidifying operation according to another embodiment of the present invention.

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

FIG. 8 is a view showing a heat source side portion of a refrigeration cycle in the conventional air conditioner.

FIG. 9 is a diagram showing a refrigeration cycle configuration of another conventional air conditioner.

FIG. 10 is a diagram showing a refrigeration cycle configuration of another conventional air conditioner.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 indoor unit 2 outdoor unit 6 first indoor heat exchanger 7 second indoor heat exchanger 8 indoor flow-through fan (indoor fan) 10 dehumidifying expansion device 12 compressor 13 outdoor fan 14 expansion valve (outdoor expansion device) 15 Four-way valve (outdoor four-way valve) 16 Four-way valve (flow path switching means) 20, 22 Bypass pipe 21, 23 Two-way valve

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F25B 41/06 F25B 41/06 AS (72) Inventor Jin Mogi 1006 Odakadoma, Kadoma City, Osaka Matsushita Electric Sangyo Co., Ltd. (72) Inventor Shoichi Yokoyama 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.F-term (reference)

Claims (8)

[Claims] An outdoor unit having a compressor, an outdoor four-way valve, an outdoor expansion device, an outdoor heat exchanger, and an outdoor fan; a first indoor heat exchanger provided on the indoor air suction side of the indoor fan; A second indoor heat exchanger connected in series with the first indoor heat exchanger on the indoor air suction side and closer to the windward side than the first indoor heat exchanger, and between the first and second indoor heat exchangers. An air conditioner configured by connecting an indoor unit having a dehumidifying expansion device provided in the outdoor four-way valve, an outdoor heat exchanger, a first indoor heat exchanger, and a second indoor heat exchanger. Connected to allow the refrigerant to flow from the first indoor heat exchanger to the second indoor heat exchanger during the heating operation and the dehumidifying operation, and from the second indoor heat exchanger to the first indoor heat exchanger during the cooling operation. Switching means for flowing the refrigerant with the air, an outdoor four-way valve, an outdoor An air conditioner comprising: a throttle device, a flow path switching unit, and a control unit for controlling a dehumidifying throttle device, and a control unit for controlling the dehumidifying throttle device to exert a throttle function only during a dehumidifying operation. 2. The air conditioner according to claim 1, wherein the control means detects the indoor temperature and the set temperature to control the switching of the outdoor four-way valve and the rotation speed of the outdoor fan. 3. The air conditioner according to claim 1, wherein a four-way valve is used as the flow path switching unit. 4. The air conditioner according to claim 3, wherein the four-way valve used as the flow path switching means is controlled so as to be energized and switched only during the dehumidifying operation. 5. An air conditioner comprising a compressor, an indoor heat exchanger, a four-way valve, an outdoor throttle device, and an outdoor heat exchanger.
In the indoor heat exchanger, a first indoor heat exchanger disposed at a leeward position on the indoor air suction side and serving as a heating unit during the dehumidifying operation, and a cooling / dehumidifying unit disposed at the leeward position on the indoor air suction side during the dehumidifying operation. A second indoor heat exchanger, and a dehumidifying expansion device disposed between the first and second indoor heat exchangers, and the inlet of the outdoor expansion device and the compressor in a dehumidification mode in the same cycle as the heating cycle. A pipe that bypasses the suction side is provided, and a two-way valve is provided in the bypass pipe. During the dehumidification operation, the outdoor throttle device is closed and the two-way valve is opened to control the first indoor heat. The four-way valve is switched so that the refrigerant flows from the first indoor heat exchanger to the second indoor heat exchanger during the heating operation, and the second valve is switched during the cooling operation. From indoor heat exchanger to first room Air conditioner, wherein a refrigerant to exchanger is provided a control means for switching the four-way valve to flow. 6. An air conditioner comprising a compressor, an indoor heat exchanger, a four-way valve, an outdoor expansion device, and an outdoor heat exchanger.
In the indoor heat exchanger, a first indoor heat exchanger disposed at a leeward position on the indoor air suction side and serving as a heating unit during the dehumidifying operation, and a cooling / dehumidifying unit disposed at the leeward position on the indoor air suction side during the dehumidifying operation. A second indoor heat exchanger, and a dehumidifying expansion device disposed between the first and second indoor heat exchangers. In the dehumidification mode of the same cycle as the cooling cycle, the outdoor expansion device outlet and the four-way valve high pressure are provided. A pipe that bypasses the side outlet is provided, and a two-way valve is provided in the bypass pipe. During the dehumidifying operation, the outdoor expansion device is closed and the two-way valve is opened to control the refrigerant to generate the first indoor heat. The four-way valve is switched so that the refrigerant flows from the first indoor heat exchanger to the second indoor heat exchanger during the heating operation, and the second valve is switched during the cooling operation. First room from indoor heat exchanger Air conditioner, wherein a refrigerant to the heat exchanger is provided with a control means for switching the four-way valve to flow. 7. The air conditioner according to claim 1, wherein the outdoor expansion device is an electric expansion valve that can be fully closed and fully opened. 8. The air conditioner according to claim 1, wherein the dehumidifying throttle device is an electric expansion valve that can be adjusted between a predetermined throttle state and a fully closed state.