JP2002243296A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance heat transfer rate by changing the flow speed of a refrigerant in an outdoor heat exchanger and an indoor heat exchanger. SOLUTION: An air conditioner comprises three systems of refrigerant flow passages 4a, 4b and 4c provided in the outdoor heat exchanger 4, and three systems of refrigerant flow passages 6a, 6b and 6c provided in the indoor heat exchanger 6. The conditioner is further provided with a first solenoid ON-OFF valve in a first bypass pipe 12 connected to one side of the outdoor heat exchanger 4, and a second solenoid ON-OFF valve 8 in a second bypass pipe 14 connected to the other side. A check valve 9 and a check valve 10 are provided respectively on a fourth bypass pipe 18 connected to one side of the heat exchanger 6, and a third bypass pipe 16 connected to the other side. In refrigerant operation, the flow speed of the refrigerant is increased in the outdoor heat exchanger 4 and the flow speed of the refrigerant is decreased in the indoor heat exchanger so as to raise heat transfer rate.

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 a structure of a plurality of refrigerant passages provided in an indoor heat exchanger and an outdoor heat exchanger.

[0002]

2. Description of the Related Art In a conventional air conditioner, a compressor circuit, a four-way valve 2, an outdoor heat exchanger 31, an expansion valve 5, and an indoor heat exchanger 32 are sequentially connected as shown in FIG. To form a refrigeration cycle. The outdoor heat exchanger 31 is provided with a refrigerant channel 31a and a refrigerant channel 31b, and the indoor heat exchanger 32 is provided with a refrigerant channel 32a and a refrigerant channel 32b.
During the cooling operation, the refrigerant discharged from the compressor 1 flows into the outdoor heat exchanger 31 via the four-way valve 2 and releases heat in the outdoor heat exchanger 31. Condensed, and then through the expansion valve 5, the indoor heat exchanger 3
2, is evaporated in the indoor heat exchanger 32, absorbs heat, and is returned to the compressor 1 through the four-way valve 2. During the heating operation, the refrigerant discharged from the compressor 1 flows into the indoor heat exchanger 32 through the four-way valve 2 and releases heat in the indoor heat exchanger 32 to be condensed. The heat flows into the outdoor heat exchanger 31 through the expansion valve 5, absorbs heat in the outdoor heat exchanger 31, evaporates, and returns to the compressor 1 through the four-way valve 2. .

[0003] However, the outdoor heat exchanger 31 and the indoor heat exchanger 32 have the same number of refrigerant flow paths,
During the cooling operation or the heating operation, the refrigerant flow path 31a and the refrigerant flow path 31b and the refrigerant flow path 32a
The flow rate and the flow rate of the refrigerant flowing through the refrigerant flow path 32b are substantially the same. During the cooling operation, the refrigerant flowing through the outdoor heat exchanger 31 has a higher heat transfer coefficient in the process of condensing and liquefying, and has a higher heat transfer coefficient. The refrigerant flowing in the indoor heat exchanger 32 has a higher flow rate in the process of evaporating. Is smaller, the pressure loss in the refrigerant passage 32a and the refrigerant passage 32b is smaller, and the heat transfer coefficient is improved. Accordingly, an air conditioner that improves the efficiency of the cooling operation or the heating operation by changing the flow rate and the flow velocity of the refrigerant flowing through the outdoor heat exchanger 31 and the indoor heat exchanger 32 has been desired.

[0004]

SUMMARY OF THE INVENTION In view of the above problems, the present invention provides a method for controlling the flow rate of refrigerant flowing through a plurality of refrigerant channels provided in an outdoor heat exchanger and an indoor heat exchanger during cooling operation and heating operation. Alternatively, it is an object of the present invention to provide an air conditioner that is switched at the time of a defrosting operation to improve a cooling coefficient of performance, a heating coefficient of performance, and defrosting efficiency.

[0005]

According to the present invention, a refrigerant circuit is constructed by sequentially connecting a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve, and an indoor heat exchanger. In the air conditioner, the outdoor heat exchanger is provided with three systems of a first refrigerant pipe, a second refrigerant pipe, and a third refrigerant pipe in a vertical direction, and the first refrigerant pipe and the second refrigerant pipe are provided. Are connected by a first U-shaped pipe on the expansion valve side, the second refrigerant pipe and the third refrigerant pipe are connected by a second U-shaped pipe on the four-way valve side, and are vertically connected to the indoor heat exchanger. Along with providing three systems of fourth refrigerant pipe, fifth refrigerant pipe and sixth refrigerant pipe in the direction,
The fourth refrigerant pipe and the fifth refrigerant pipe are connected by a third U-shaped pipe on the expansion valve side, and the fifth refrigerant pipe and the sixth refrigerant pipe are connected by a fourth U-shaped pipe on the four-way valve side. And the first refrigerant pipe is connected to the four-way valve by a first pipe, and the first pipe and the second U-shaped pipe are connected to a first bypass pipe having a first solenoid on-off valve. Connecting the third refrigerant pipe to the expansion valve by a second pipe, connecting a second bypass pipe provided with a second electromagnetic on-off valve to the second pipe and the first U-shaped pipe, Six refrigerant pipes and the expansion valve are connected by a third pipe, and the third pipe and the third U
And a third bypass pipe provided with a check valve in which the expansion valve is on the upstream side, and the fourth refrigerant pipe is connected to the four-way valve by a fourth pipe. The fourth U-shaped pipe is connected to a fourth bypass pipe provided with a check valve in which the indoor heat exchanger is on the upstream side. During cooling operation, the four-way valve is connected to the outdoor heat exchanger through the four-way valve. While switching so that the refrigerant flows toward the device, the first solenoid on-off valve and the second solenoid on-off valve are each closed, and the refrigerant flowing into the outdoor heat exchanger flows from the first refrigerant pipe through the first refrigerant pipe. The refrigerant sequentially flows into the third refrigerant pipe via the two refrigerant pipes, and the refrigerant flowing into the indoor heat exchanger from the expansion valve is parallel to the fourth refrigerant pipe, the fifth refrigerant pipe, and the sixth refrigerant pipe, respectively. By flowing, the flow rate of the refrigerant flowing through the outdoor heat exchanger flows through the indoor heat exchanger. Set to be larger than the flow rate of the coolant, which is to become increasing constituting the heat exchange amount at the outdoor heat exchanger.

In the heating operation, the four-way valve is switched so that the refrigerant flows from the four-way valve toward the indoor heat exchanger, and the first electromagnetic on-off valve and the second electromagnetic on-off valve are switched. Each of the refrigerants opened and the refrigerant flowing into the indoor heat exchanger flows sequentially from the fourth refrigerant pipe through the fifth refrigerant pipe to the sixth refrigerant pipe, and flows from the expansion valve into the outdoor heat exchanger. Flows in parallel through the first refrigerant pipe, the second refrigerant pipe, and the third refrigerant pipe, thereby increasing the amount of heat exchange in the indoor heat exchanger.

Further, during the defrosting operation, the four-way valve is switched so that the refrigerant flows from the four-way valve toward the outdoor heat exchanger, and the first electromagnetic on-off valve and the second electromagnetic on-off valve are switched. Respectively, the refrigerant flowing into the outdoor heat exchanger flows in parallel through the first refrigerant pipe, the second refrigerant pipe, and the third refrigerant pipe, respectively, from the expansion valve to the indoor heat exchanger. The inflowing refrigerant flows in the fourth refrigerant pipe, the fifth refrigerant pipe, and the sixth refrigerant pipe in parallel.

[0008]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a refrigerant circuit diagram of an air conditioner according to the present invention, and FIG.
FIG. 2A is a refrigerant circuit diagram illustrating a flow of a refrigerant during a cooling operation, and FIG. 2B is a refrigerant circuit diagram illustrating a flow of a refrigerant during a heating operation. FIG. 3A is a refrigerant circuit diagram showing the flow of the refrigerant during the defrosting operation, and FIG. 3B is a diagram showing the open / closed state of the electromagnetic on-off valve during each operation. The air conditioner according to the present invention includes a compressor 1 as shown in FIG.
The four-way valve 2, the outdoor heat exchanger 4, the expansion valve 5, the indoor heat exchanger 6, and the accumulator 3 are sequentially connected to form a refrigerant circuit, and the outdoor heat exchanger 4 is vertically connected to three systems. A first refrigerant pipe 4a, a second refrigerant pipe 4b, and a third refrigerant pipe 4c are provided, and the first refrigerant pipe 4a and the second refrigerant pipe 4c are provided.
b on the expansion valve 5 side by a first U-shaped pipe 4d,
The second refrigerant pipe 4b and the third refrigerant pipe 4c are connected by a second U-shaped pipe 4e on the four-way valve 2 side. Further, the indoor heat exchanger 6 is provided with three fourth refrigerant pipes 6 in the vertical direction.
a, a fifth refrigerant pipe 6b and a sixth refrigerant pipe 6c are provided, and the fourth refrigerant pipe 6a and the fifth refrigerant pipe 6b are connected by a third U-shaped pipe 6d on the expansion valve 5 side. The fifth refrigerant pipe 6b and the sixth refrigerant pipe 6c are connected by a fourth U-shaped pipe 6e on the four-way valve 2 side.

The four-way valve 3 and the first refrigerant pipe 4a of the outdoor heat exchanger 4 are connected by a first pipe 11, and the first pipe 11 and the second U-shaped pipe 4e have a first pipe. A first bypass pipe 12 having an electromagnetic on-off valve 7 is connected, the expansion valve 5 and the third refrigerant pipe 4c are connected by a second pipe 13, and the second pipe 13 and the first U-shaped pipe 4d. Is connected to a second bypass pipe 14 having a second electromagnetic on-off valve 8. The expansion valve 5 and the sixth refrigerant pipe 6 c of the indoor heat exchanger 6 are connected by a third pipe 15.
5 and the third U-shaped pipe 6d, a third bypass pipe 16 provided with a check valve 10 in which the expansion valve 5 is on the upstream side is connected, and the four-way valve 2 and the indoor heat exchanger 6 are connected to each other. The fourth refrigerant pipe 6a is connected to the fourth refrigerant pipe 6a by a fourth pipe 17,
A fourth bypass pipe 18 having a check valve 9 in which the indoor heat exchanger 6 is on the upstream side is connected to 7 and the fourth U-shaped pipe 6e.

Next, the flow of the refrigerant during the cooling operation will be described. During the cooling operation, the first solenoid on-off valve 7 and the second solenoid on-off valve 8 are closed as shown in FIG. The refrigerant discharged from the compressor 1 flows into the first bypass pipe 12 through the pipe 11 through the four-way valve 2 as shown in FIG. The flow is interrupted because 7 is closed. The refrigerant flowing into the first refrigerant pipe 4a from the first pipe 11 is
Since the second solenoid on-off valve 8 is closed, it flows into the second refrigerant pipe 4b via the first U-shaped pipe 4d, and the first solenoid on-off valve 7 is closed. The refrigerant flows into the third refrigerant pipe 4c via the two U-shaped pipes 4e, and releases heat and condenses them. The condensed refrigerant subsequently passes through the second pipe 13 and is reduced in pressure by the expansion valve 5 to a low pressure. From the three pipes 15 and the third bypass pipe 16, the fourth refrigerant pipe 6a, the fifth refrigerant pipe 6b and The refrigerant flows into the sixth refrigerant pipe 6c, respectively, flows in parallel, flows through the fourth bypass pipe 18 and the fourth pipe 17, and returns to the compressor 1 via the four-way valve 2.

As described above, during the cooling operation, in the outdoor heat exchanger 4, refrigerant flows from the first refrigerant pipe 4a through the second refrigerant pipe 4b to the third refrigerant pipe 4c in a long heat transfer pipe. , The flow velocity increases, thereby improving the heat transfer coefficient in the outdoor heat exchanger 4. Further, in the indoor heat exchanger 6, the refrigerant flows in parallel through the fourth refrigerant pipe 6a, the fifth refrigerant pipe 6b, and the sixth refrigerant pipe 6c, so that the flow velocity is reduced and the pressure loss is reduced. The heat transfer coefficient is improved.

Next, the flow of the refrigerant during the heating operation will be described. During the heating operation, the first solenoid on-off valve 7 and the second solenoid on-off valve 8 are opened as shown in FIG. The refrigerant discharged from the compressor 1 flows into the fourth refrigerant pipe 6a of the indoor heat exchanger 6 through the fourth pipe 17 via the four-way valve 2 as shown in FIG. 2 (B). .
The refrigerant flowing into the fourth bypass pipe 18 is supplied to the check valve 9.
Blocks the flow. The refrigerant flowing into the fourth refrigerant pipe 6a passes through the fifth refrigerant pipe 6b and the sixth refrigerant pipe 6c, flows into the expansion valve 5 from the third pipe 15, and is decompressed. It branches into a pipe 13 and the second bypass pipe 14 and flows into the first refrigerant pipe 4a, the second refrigerant pipe 4b, and the third refrigerant pipe 4c of the outdoor heat exchanger 4, respectively. The refrigerant that has exchanged heat therethrough passes through the first pipe 11 and the first bypass pipe 12 and passes through the four-way valve 2.
To the compressor 1 through the compressor.

As described above, during the heating operation, in the indoor heat exchanger 6, refrigerant flows from the fourth refrigerant pipe 6a through the fifth refrigerant pipe 6b to the sixth refrigerant pipe 6c in a long heat transfer pipe. , The flow velocity increases, and thereby the heat transfer coefficient in the indoor heat exchanger 6 improves. In the outdoor heat exchanger 4, the refrigerant flows in the first refrigerant pipe 4a, the second refrigerant pipe 4b, and the third refrigerant pipe 4c in parallel, so that the flow velocity is reduced, and the pressure loss is reduced. The heat transfer coefficient is improved.

When performing the heating operation in winter, if frost adheres to the outdoor heat exchanger 4, it is necessary to perform the defrosting operation before the heating operation. Next, the flow of the refrigerant during the defrosting operation will be described. During the defrosting operation, the first solenoid on-off valve 7 and the second solenoid on-off valve 8 are opened as shown in FIG. The refrigerant discharged from the compressor 1 is shown in FIG.
As shown in (A), the heat flows into the first refrigerant pipe 4a, the second refrigerant pipe 4b, and the third refrigerant pipe 4c of the outdoor heat exchanger 4 via the four-way valve 2 to release heat. Then, the outdoor heat exchanger 4 is defrosted. The refrigerant that has released the heat flows from the third pipe 15 through the expansion valve 5 into the fourth refrigerant pipe 6a, the fifth refrigerant pipe 6b, and the sixth refrigerant pipe 6c of the indoor heat exchanger 6, respectively. Then, the refrigerant is returned to the compressor 1 through the four-way valve 2.

As described above, during the defrosting operation, the compressor 1
High-temperature and high-pressure refrigerant discharged from the outdoor heat exchanger 4
The first refrigerant pipe 4a, the second refrigerant pipe 4b, and the third refrigerant pipe 4c flow in parallel to release heat, thereby improving the efficiency of the defrosting operation.

[0016]

As described above, according to the present invention,
The outdoor heat exchanger and the indoor heat exchanger are each provided with three refrigerant flow paths, and electromagnetic valves are provided on bypass pipes connected to both sides of the outdoor heat exchanger, respectively. Check valves are provided in the bypass pipes connected to the
During the refrigerant operation, the flow rate of the refrigerant is increased in the outdoor heat exchanger, and the heat transfer rate is improved by decreasing the flow rate of the refrigerant in the indoor heat exchanger. By increasing the flow rate and decreasing the flow rate of the refrigerant in the outdoor heat exchanger, the heat transfer rate is improved, and an air conditioner with improved efficiency of the cooling / heating operation or the defrosting operation can be obtained.

[Brief description of the drawings]

FIG. 1 is a refrigerant circuit diagram of an air conditioner according to the present invention.

FIG. 2A is a refrigerant circuit diagram showing a flow of a refrigerant during a refrigerant operation of the air conditioner according to the present invention. (B) is a refrigerant circuit diagram showing a refrigerant flow during a heating operation of the air conditioner according to the present invention.

FIG. 3A is a refrigerant circuit diagram showing a refrigerant flow during a defrosting operation of the air conditioner according to the present invention. (B) is a figure which shows the opening / closing state of the solenoid on-off valve provided in the refrigerant circuit of the air conditioner by this invention.

FIG. 4 is a refrigerant circuit diagram of an air conditioner according to a conventional example.

[Explanation of symbols]

 Reference Signs List 1 compressor 2 four-way valve 3 accumulator 4 outdoor heat exchanger 4a first refrigerant pipe 4b second refrigerant pipe 4c third refrigerant pipe 4d first U-shaped pipe 4e second U-shaped pipe 5 expansion valve 6 indoor heat exchanger 6a Four refrigerant pipe 6b Fifth refrigerant pipe 6c Sixth refrigerant pipe 6d Third U-shaped pipe 6e Fourth U-shaped pipe 7 First electromagnetic on-off valve 8 Second electromagnetic on-off valve 9 Check valve 10 Check valve 11 First pipe 12 First bypass pipe 13 Second pipe 14 Second bypass pipe 15 Third pipe 16 Third bypass pipe 17 Fourth pipe 18 Fourth bypass pipe

Claims (3)

[Claims] 1. A compressor, a four-way valve, an outdoor heat exchanger,
In an air conditioner configured by sequentially connecting an expansion valve and an indoor heat exchanger to form a refrigerant circuit, the outdoor heat exchanger has three first refrigerant pipes in a vertical direction;
A second refrigerant pipe and a third refrigerant pipe are provided, the first refrigerant pipe and the second refrigerant pipe are connected by a first U-shaped pipe on the expansion valve side, and the second refrigerant pipe and the third refrigerant pipe are connected. A pipe is connected to the four-way valve side by a second U-shaped pipe, and the indoor heat exchanger is provided with three systems of a fourth refrigerant pipe, a fifth refrigerant pipe, and a sixth refrigerant pipe in a vertical direction, and A refrigerant pipe and the fifth refrigerant pipe are connected by a third U-shaped pipe on the expansion valve side, and the fifth refrigerant pipe and the sixth refrigerant pipe are connected by a fourth U-shaped pipe on the four-way valve side. Connecting the first refrigerant pipe to the four-way valve by a first pipe, connecting a first bypass pipe provided with a first electromagnetic on-off valve to the first pipe and the second U-shaped pipe, The three refrigerant pipes are connected to the expansion valve by a second pipe, and the second pipe and the first U-shaped pipe are provided with a second solenoid valve. The second bypass pipe is connected, and the sixth refrigerant pipe and the expansion valve are connected by a third pipe, and the third pipe and the third U-shaped pipe have the expansion valve on the upstream side. A third bypass pipe having a check valve is connected, the fourth refrigerant pipe is connected to the four-way valve by a fourth pipe, and the indoor heat exchange is performed between the fourth pipe and the fourth U-shaped pipe. A fourth bypass pipe provided with a check valve on the upstream side of the vessel is connected, and during the cooling operation, the four-way valve is switched so that the refrigerant flows from the four-way valve toward the outdoor heat exchanger. The first solenoid on-off valve and the second solenoid on-off valve are each closed, and the refrigerant flowing into the outdoor heat exchanger flows sequentially from the first refrigerant pipe through the second refrigerant pipe to the third refrigerant pipe. The refrigerant flowing from the expansion valve into the indoor heat exchanger is the fourth refrigerant pipe and the fifth refrigerant. By flowing the pipe and the sixth refrigerant pipe in parallel, the flow rate of the refrigerant flowing through the outdoor heat exchanger is larger than the flow rate of the refrigerant flowing through the indoor heat exchanger. An air conditioner characterized by increasing the amount of heat exchange. 2. During a heating operation, the four-way valve is switched so that refrigerant flows from the four-way valve toward the indoor heat exchanger, and the first electromagnetic on-off valve and the second electromagnetic on-off valve are connected to each other. Each of the refrigerants opened and the refrigerant flowing into the indoor heat exchanger flows sequentially from the fourth refrigerant pipe through the fifth refrigerant pipe to the sixth refrigerant pipe, and flows from the expansion valve into the outdoor heat exchanger. Flowing in parallel through the first refrigerant pipe, the second refrigerant pipe, and the third refrigerant pipe, thereby increasing an amount of heat exchange in the indoor heat exchanger. The air conditioner according to item 1. 3. During the defrosting operation, the four-way valve is switched so that refrigerant flows from the four-way valve toward the outdoor heat exchanger, and the first electromagnetic on-off valve and the second electromagnetic on-off valve Respectively, the refrigerant flowing into the outdoor heat exchanger flows in parallel through the first refrigerant pipe, the second refrigerant pipe, and the third refrigerant pipe, respectively, from the expansion valve to the indoor heat exchanger. The air conditioner according to claim 1, wherein the inflowing refrigerant flows in parallel through the fourth refrigerant pipe, the fifth refrigerant pipe, and the sixth refrigerant pipe, respectively.