JPH07293975A - Air conditioner - Google Patents

Abstract

PURPOSE:To obtain a multisplit air conditioner in which a load to be applied at the time of operating one indoor heat exchanger is reduced and durability of the unit is enhanced. CONSTITUTION:A tube for connecting a liquid receiver 10 and a compressor 1 is connected to a tube for connecting indoor heat exchangers 7 and 9 to an outdoor heat exchanger 3 via a distributor 5 and an expansion valve 7 via a four-way valve 6. Solenoid valves 6, 8 are provided between the exchangers 7, 9 and the distributor 5. Bypass pipelines 7, 13 having check valves 12, 14 are connected to the receiver 10 via a solenoid valve 16 so controlled as to be open when either the valve 6 or 8 is closed via part of the 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 a refrigeration cycle for a multi-room air conditioner.

[0002]

2. Description of the Related Art A multi-room air conditioner is shown in FIG.
During the cooling operation, the high temperature and high pressure refrigerant discharged from the compressor 1 reaches the outdoor heat exchanger 3 through the four-way valve 2 as shown by the path indicated by the solid line arrow and exchanges heat to become a high temperature and high pressure liquid. The pressure is reduced by the expansion valve 4 via the stop valve 17, evaporated by the indoor heat exchangers 7 and 9 in which the electromagnetic valve 6, the indoor heat exchanger 7 and the electromagnetic valve 8, and the indoor heat exchanger 9 are connected in parallel, and a four-way valve 2,
A circulation cycle is formed in which the compressor 1 is sucked again through the liquid receiver 10. Further, during the heating operation, the four-way valve 2 is switched, and the refrigerant from the compressor 1 passes through the four-way valve 2 and the indoor heat exchangers 7 and 9 as shown by the path indicated by the broken line arrow, the expansion valve 4, and the outdoor heat exchange It is evaporated in the container 3, and is again sucked into the compressor 1 via the four-way valve 2 and the liquid receiver 10. However, when performing one-sided operation by either one of the indoor heat exchangers 7 and 9, the liquid refrigerant cannot be completely evaporated by the capacity of the indoor heat exchangers 7 and 9 during the cooling operation, and the liquid refrigerant cannot be received. It may flow back to the liquid container 10 and a part of the liquid may be sucked into the compressor 1, which may cause a hindrance to the operation of the compressor 1. In order to prevent this, it was necessary to increase the capacity of the liquid receiver 10. Further, in the case of the one-side operation of the indoor heat exchangers 7 and 9 during the heating operation, the heat exchange is not sufficiently performed inside the indoor heat exchangers 7 and 9, so that the discharge pressure of the compressor 1 rises and the compressor is increased. Was sometimes overloaded.

[0003]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above points, and even if the indoor heat exchanger is operated by one side operation, the refrigerant is evaporated by the indoor heat exchanger during the cooling operation. (EN) An air conditioner that reduces the amount of liquid refrigerant returned to a receiver as liquid refrigerant and reduces the load on the compressor during heating operation.

[0004]

In order to solve the above-mentioned problems, the present invention branches a first bypass passage connecting a check valve between the expansion valve and the solenoid valve, and at the same time, the indoor heat exchanger. A second bypass path connecting the check valve in the opposite direction to the check valve from between the four-way valve and the third bypass to join the first bypass path and the second bypass path. The third bypass passage is disposed in the outdoor heat exchanger in a heat exchange manner, and a third solenoid valve is connected to allow the fluid to flow back to the liquid receiver, and the first solenoid valve or the second solenoid valve is connected. If any one of the solenoid valves is closed, the third solenoid valve is controlled to be opened.

[0005]

Since the air conditioner according to the present invention is configured as described above, even if one side of the indoor heat exchanger is operated by one side, a part of the refrigerant passes through the bypass passage to the outdoor heat exchanger. As a result, the amount of liquid refrigerant returned to the liquid receiver during cooling operation can be reduced, and the load on the compressor can be reduced during heating operation.

[0006]

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 illustrates a refrigeration cycle of an air conditioner according to the present invention. The same or corresponding parts as those of the conventional example are designated by the same reference numerals. The compressor 1 has a connection pipe 19
Connected to the four-way valve 2 and connected pipe 2 from the four-way valve 2
1 via the outdoor heat exchanger 3 and via the check valve 17 in which the capillary tubes 18 are connected in parallel to the expansion valve 4. The pipe line branched by the distributor 5 is connected in parallel to a pipe line 22 connecting the solenoid valve 6 and the indoor heat exchanger 7 and a pipe line 23 connecting the solenoid valve 8 and the indoor heat exchanger 9, The passages 22 and 23 join and the connecting pipe 2
4 and is connected to the four-way valve 2. The four-way valve 2 is connected to the compressor 1 via a connection pipe 20 and a liquid receiver 10. A first bypass passage 11 to which a check valve 14 is connected is branched from between the expansion valve 4 and the distributor 5, and a second bypass passage to which a check valve 15 is connected from the connection pipe 24. Are connected.
The check valve 14 and the check valve 15 are connected in opposite directions,
Refrigerants do not flow into each other's bypass passages. The bypass passage 11 and the bypass passage 12 merge and are connected to a third bypass passage 13. The bypass passage 13 is connected to the connection pipe 20 via an electromagnetic valve 16 after passing through the outdoor heat exchanger 3. Has been done.

The solenoid valves 6 and 8 and the solenoid valve 16 are controlled by a control device 25, and when either one of the solenoid valves 6 and 8 is closed, the solenoid valve 16 is set to an open state. Has been done.

Next, the operation of the air conditioner having the above structure will be described. During the cooling operation, the indoor heat exchanger 7,
When both 9 are operated, both the solenoid valves 6 and 8 are opened, and the solenoid valve 16 is closed by the control device 25 as described above. As a result, the refrigerant cannot flow into the bypass passages 11 and 12, and the refrigerant is evaporated by the indoor heat exchangers 7 and 9. The indoor heat exchangers 7, 9
When operating either one of the above, the solenoid valves 6 and 8
One of the two is closed and the control device 25 opens the solenoid valve 16. As shown in FIG. 3, the high temperature and high pressure refrigerant discharged from the compressor 1 is heat-exchanged by the outdoor heat exchanger 3 through the four-way valve 2 to become a high temperature and high pressure liquid,
Although the pressure is reduced by the expansion valve 4, the refrigerant is the indoor heat exchanger 7,
9 and one of them is part of the first
To the outdoor heat exchanger 3 through the third bypass passage 13 to be evaporated and flow into the connection pipe 20. As a result, the refrigerant that cannot be completely evaporated by only the one-side operation of the indoor heat exchangers 7 and 9 is evaporated by the outdoor heat exchanger 3 and returned to the liquid receiver 10 in the liquid refrigerant state, and the amount of the refrigerant is reduced as much as possible. it can.

Even during the heating operation, as shown in FIG. 3, when one side operation of one of the indoor heat exchangers 7 and 9 is performed, one of the solenoid valves 6 and 8 is closed. As a result, the solenoid valve 16 is opened. The high-temperature, high-pressure refrigerant discharged from the compressor 1 flows into the indoor heat exchangers 7 and 9 through the four-way valve 2, but a part of the refrigerant flows into the second bypass passage 12 and the bypass passage 13. After that, it reaches the outdoor heat exchanger 3 and is evaporated. As a result, the overload state of the compressor 1 due to heat exchange by the one-sided operation of the indoor heat exchangers 7 and 9 is reduced.

[0010]

As described above, in the air conditioner according to the present invention, when the indoor heat exchanger is operated on one side, a part of the refrigerant flowing out of the expansion valve is bypassed during the cooling operation. By evaporating through the outdoor heat exchanger through the outdoor heat exchanger, the amount of liquid refrigerant returned to the liquid receiver can be reduced, and the liquid receiver can be downsized, and the liquid refrigerant mixed in the compressor can be reduced, The durability of the air conditioner is increased, and the reliability of the air conditioner is improved.During heating operation, part of the refrigerant passes through the bypass pipe and evaporates by the outdoor heat exchanger, so that only one indoor heat exchanger operates. It is possible to reduce the overload on the compressor and improve the durability of the device.

[Brief description of drawings]

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

FIG. 2 is a diagram showing a refrigerant flow path during a cooling operation of the air conditioner according to the present invention.

FIG. 3 is a diagram showing a refrigerant flow path during a heating operation of the air conditioner according to the present invention.

FIG. 4 is a piping diagram showing an air conditioner according to a conventional example.

[Explanation of symbols]

 1 Compressor 2 Four-way valve 3 Outdoor heat exchanger 4 Expansion valve 5 Distributor 6 Electromagnetic valve 7 Indoor heat exchanger 8 Electromagnetic valve 9 Indoor heat exchanger 10 Liquid receiver 11 Bypass passage 12 Bypass passage 13 Bypass passage 14 Check valve 15 Check valve 16 Solenoid valve 17 Check valve 18 Capillary tube 19 Connection pipe 20 Connection pipe

Claims (1)

[Claims] 1. A compressor, a four-way valve, an outdoor heat exchanger, an expansion valve, a first solenoid valve in parallel, a first indoor heat exchanger and a second solenoid valve, a second indoor heat exchanger and a receiver. In an air conditioner that is connected to a liquid vessel in order by piping to form a refrigeration cycle,
The first bypass path connecting the check valve between the expansion valve and the solenoid valve is branched, and the check valve in the opposite direction to the check valve is connected between the indoor heat exchanger and the four-way valve. While branching the second bypass path, a third bypass path connecting the third electromagnetic valve is branched from between the four-way valve and the liquid receiver to allow a part of the outdoor heat exchanger to pass. At the same time, the first bypass passage, the second bypass passage, and the third bypass passage are merged, and if either the first solenoid valve or the second solenoid valve is closed, the third solenoid passage is closed. An air conditioner characterized by controlling the valve to open.