JPH06100388B2 - Separate type air conditioner - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a heat pump type separate air conditioner, and more specifically, recovers a filled refrigerant in a refrigerant circulation circuit to an outdoor unit side at the time of inspection or repair. The present invention relates to an air conditioner including a refrigerant recovery circuit.

(Prior Art) Generally, when inspecting or repairing a separate type air conditioner, a pump down operation is performed in advance to collect the filled refrigerant in the refrigerant circulation circuit to the outdoor unit side to prevent refrigerant loss. At the same time, work safety is ensured.
In such a pump down, in the air conditioner or the air conditioner and the air conditioner, the refrigerant circulation cycle is operated in the air cooling cycle, and the refrigerant pipe between the outdoor heat exchanger and the indoor heat exchanger is closed by the liquid closing valve. It is possible to cause the outdoor heat exchanger to act as a condenser, collect the filled refrigerant in the refrigerant circulation circuit in the outdoor heat exchanger, collect the refrigerant, and pump down (for example, Japanese Utility Model Publication No. 58-54609). , Actual Kai Sho 57-16007
(See Gazette No. 2). On the other hand, since the air conditioner dedicated to heating does not have a cooling cycle, it is difficult to recover the refrigerant to the outdoor heat exchanger or the like in the refrigerant circulation circuit as it is. Therefore, the applicant previously proposed an improved refrigerant circuit so that the refrigerant can be easily recovered in an air conditioner dedicated to heating (Japanese Patent Application No. 60-240245).
issue). The refrigerant piping system diagram is shown in FIG. In the figure, 30 is an outdoor unit, 40 is an indoor unit, and the outdoor unit 30 has a compressor 51, an outdoor heat exchanger 52 acting as an evaporator, a decompression mechanism 53 composed of a capillary tube, and an accumulator 54. And one-way guidance unit
40 has an indoor heat exchanger 55 which acts as a condenser. The discharge port of the compressor 51 and the indoor heat exchanger 55 are connected by a first gas pipe 56 and a second gas pipe 57, and between the first gas pipe 56 and the second gas pipe 57. A gas closing valve 58 consisting of a three-way valve is provided. Also, the indoor heat exchanger
55 and the outdoor heat exchanger 52 are connected by a first liquid pipe 59 and a second liquid pipe 60 in which the pressure reducing mechanism 53 is interposed,
A liquid closing valve 61, which is a three-way valve, is interposed between the first liquid pipe 59 and the second liquid pipe 60. Further, the outdoor heat exchanger 52 is connected to the accumulator 54 by the third gas pipe 62, and the accumulator 54 is connected to the compressor 51 by the suction pipe 63.
And a refrigerant circulation circuit is formed.

On the other hand, the first gas pipe 56 connecting the compressor 51 and the gas shutoff valve 58 has a first bypass pipe 65 in which an electromagnetic valve 64 is interposed.
Is connected to the second liquid pipe 60.

Further, in this device, the surplus port of the gas closing valve 58, which is a three-way valve, is used as a check valve to enable pump down.
The third bypass pipe 67 is provided with a second bypass pipe 67.
It is connected to the gas pipe 62.

In the apparatus having the above configuration, when the pump down operation is performed, first, the liquid closing valve 61 is switched so that the first liquid pipe 59 and the second liquid pipe 60 are shut off, and the first gas pipe 56 and the second gas pipe 56 are disconnected. tube
57 is cut off, and the gas closing valve 58 is switched so that the second gas pipe 57 communicates with the second bypass pipe 67. Further, the solenoid valve 64 in the first bypass pipe 65 is opened to operate the outdoor blower fan (not shown) attached to the compressor 51 and the outdoor heat exchanger 52. At this time, the refrigerant discharged from the compressor 51 passes directly through the first bypass pipe 65 to the outdoor heat exchanger 52.
And is liquefied and accumulated in the accumulator 54 through the third gas pipe 62. On the other hand, the refrigerant in the second gas pipe 57, the indoor heat exchanger 55, and the first liquid pipe 59 passes through the gas shutoff valve 58 and the second bypass pipe 67, and by the action of the low pressure on the suction side of the compressor 51. The liquid refrigerant is sucked toward the third gas pipe 62 side and sent to the accumulator 54, where the liquid refrigerant is accumulated and the gas refrigerant is
Returned to the compressor 51. After that, it is sent to the outdoor heat exchanger 52 through the first bypass pipe 65 in the same manner as described above, where cooling /
It is liquefied and collected by the accumulator 54.

(Problems to be Solved by the Invention) However, the above-mentioned conventional device has a drawback that it takes a long time to pump down. It is a compressor 5
1, first bypass pipe 65, outdoor heat exchanger 52, third gas pipe 6
2, in the bypass circulation path consisting of the accumulator 54, the suction pipe 63, there is no one that has such a large fluid resistance to the refrigerant flow, therefore, while the gas refrigerant circulating through this bypass circulation path exists This is because even on the suction side, the pressure acting as the refrigerant suction force on the indoor unit 40 side does not become so low. Therefore, since the high-pressure gas refrigerant and the high-pressure liquid refrigerant are blocked on the indoor unit 30 side in the initial stage of pump down, a refrigerant flow from the indoor unit 30 side through the second bypass pipe 67 may occur depending on the pressure difference. , Indoor unit 30 side and suction pipe 63
After the pressures of and become almost equal, the circulating gas refrigerant is cooled in the outdoor heat exchanger 52 and is liquefied and accumulated in the accumulator, whereby the circulating gas refrigerant amount is reduced, and this changes. The amount of refrigerant recovery thereafter depends on the degree of pressure decrease on the suction side of the compressor 51.
However, the condensation in the outdoor heat exchanger 52 is less likely to occur as the pressure of the gas refrigerant is lower, and therefore the suction side pressure of the compressor 51 becomes lower as the pressure becomes lower, so that the refrigerant on the indoor unit 40 side is completely removed. It took a long time to recover.

The present invention has been made to solve the above-mentioned conventional drawbacks, and an object thereof is to provide a separate type air conditioner capable of recovering a refrigerant in an indoor unit to an outdoor unit side in a short time. is there.

(Means for Solving Problems) Therefore, the separate air conditioner of the present invention is provided with the compressor 3
, An outdoor unit 1 having an outdoor heat exchanger 4 and an accumulator 16, and an indoor unit 2 having an indoor heat exchanger 5.
Form a refrigerant circulation circuit with the compressor 3 and the indoor heat exchanger 5 connected by the first gas pipe 6 and the second gas pipe 7, and a gas closing valve 8 between the both gas pipes 6, 7. The indoor heat exchanger 5 and the outdoor heat exchanger 4 are connected to the first liquid pipe 9 and the second liquid pipe 10.
And a liquid shutoff valve 11 between both liquid pipes 9 and 10,
Further, the outdoor heat exchanger 4 and the suction port of the compressor 3 are connected to the third
The gas pipe 13 is connected to the suction pipe 14 in which the accumulator 16 is interposed, and the third gas pipe 13 and the suction pipe 14 are connected.
And a second bypass pipe 17 having a first opening / closing means 18 for connecting the first gas pipe 6 and the second liquid pipe 10 to each other. 7 or the first liquid pipe 9 and the suction pipe 14 are connected by a second bypass pipe 19 having a second opening / closing means 15. In FIG. 1, the three-way valve 15 has two functions of the shutoff valve and the second opening / closing valve, but they may be provided separately.

(Operation) In the above-described separate type air conditioner, the pump down operation closes the gas closing valve 8, the liquid closing valve 11 and the shutoff valve 15, respectively, and the first opening / closing means 18 and the second closing means 15
It is carried out with and opened. At this time, the refrigerant gas directly supplied from the compressor 3 to the outdoor heat exchanger 4 through the first bypass pipe 17 has the third gas pipe 13 blocked by the shutoff valve 15, so that the third gas pipe 13 and the outdoor heat exchanger 4 are closed. The heat is accumulated in the heat exchanger 4, while the indoor heat exchanger 5 side is provided with the second bypass pipe 19
Through the suction pipe 14 and
Since the third gas pipe 13 that has been communicated with is shut off by the shut-off valve 15, the suction side of the compressor 3 functions exclusively for sucking the refrigerant on the indoor unit 2 side, and the amount of refrigerant on the indoor unit 2 side is reduced. As the pressure decreases, the pressure in the suction pipe 14 sharply decreases, and the suction force further increases, which enables the recovery of the refrigerant on the output unit side in a short time.

(Examples) Next, specific examples of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a refrigerant piping system in an embodiment of the separate type air conditioner of the present invention. In FIG. 1, 1 is an outdoor unit, 2 is an indoor unit, and the outdoor unit 1 is a compressor 3 And an outdoor heat exchanger 4 acting as an evaporator, while the indoor unit 2 has an indoor heat exchanger 5 acting as a condenser. The compressor 3 and the indoor heat exchanger 5 are connected by a first gas pipe 6 and a second gas pipe 7, and a three-way valve is provided between the first gas pipe 6 and the second gas pipe 7. The gas closing valve 8 is provided. Further, the indoor heat exchanger 5 and the outdoor heat exchanger 4 are connected by a first liquid pipe 9 and a second liquid pipe 10, and between the first liquid pipe 9 and the second liquid pipe 10. A liquid closing valve 11 made of a three-way valve is provided, and a pressure reducing mechanism 12 made of a capillary tube is provided in the second liquid pipe 10. Further, the outdoor heat exchanger 4 is connected to the suction port of the compressor 3 by a third gas pipe 13 and a suction pipe 14, and a shutoff valve 15 is provided between the third gas pipe 13 and the suction pipe 14. Further, an accumulator 16 is provided in the suction pipe 14.

On the other hand, the first gas pipe 6 that connects the compressor 3 and the gas shutoff valve 8 is connected to the second liquid pipe 10 by a first bypass pipe 17, and in the middle of the first bypass pipe 17, A normally closed electromagnetic valve 18 serving as a first opening / closing means for opening / closing the conduit of the first bypass pipe 17 is provided. The electromagnetic valve 18 is opened, and the gas closing valve 8 and the liquid closing valve 11 are operated to connect the first gas pipe 6 and the second gas pipe 7, and the first liquid pipe 9 and the second liquid. By operating the compressor 3 in a state in which the communication passages with the pipes 10 are closed, the refrigerant discharged from the compressor 3 circulates only in the outdoor unit 1 as indicated by the broken line arrow in the drawing. A circuit is formed. This bypass circulation circuit enables defrosting of the outdoor heat exchanger 4, and operates the compressor 3 with the outdoor blower fan (not shown) attached to the outdoor heat exchanger 4 stopped. By doing so, the hot gas discharged from the compressor 3 is directly sent to the outdoor heat exchanger 4 through the first bypass pipe 17, whereby the heat quantity of the gas refrigerant is given to the outdoor heat exchanger 4. Then, the outdoor heat exchanger 4 is defrosted.

In addition, this device allows pump down,
A surplus port of the liquid closing valve 11 formed of a three-way valve and a surplus port of the shutoff valve 15 also formed of a three-way valve are connected by a second bypass pipe 19. Therefore, the shut-off valve 15 constituted by the three-way valve has a function of shutting off the third gas pipe 13, and also serves as a second opening / closing means for opening / closing the pipeline of the second bypass pipe 19. 2 Shut-off valve 15
The schematic diagram of the operating state of FIG. The shut-off valve 15 is a ball valve type three-way valve, and in the state of FIG. 2 (A), the third gas pipe 13 and the suction pipe 14 communicate with each other, and the pipe line of the second bypass pipe 19 is In the state of FIG. 2B which is cut off and rotated 90 degrees clockwise from the state of FIG. 3A, the second bypass pipe 19 and the suction pipe 14 communicate with each other and the third gas pipe 13 That is, the pipeline is cut off.

Next, the operating state of the separate air conditioner will be described. During the heating operation, the gas shutoff valve 8 is provided at a position where the first gas pipe 6 and the second gas pipe 7, the first liquid pipe 9 and the second liquid pipe 10, and the third gas pipe 13 and the suction pipe 14 communicate with each other. Set the liquid closing valve 11 and the shutoff valve 15. At this time, the second bypass pipe 19 is blocked at both ends by the liquid closing valve 11 and the shutoff valve 15. Further, the electromagnetic valve 18 is closed to operate the compressor 3. The high-pressure gas refrigerant discharged from the compressor 3 is sent to the indoor heat exchanger 5 through the first gas pipe 6 and the second gas pipe 7 as shown by the solid line arrow in FIG. And becomes high-pressure liquid refrigerant. This high pressure liquid refrigerant is the first
It is sent through the liquid pipe 9 and the second liquid pipe 10, and at this time, the second liquid pipe
It becomes a low-pressure liquid refrigerant when passing through a decompression mechanism 12 provided in 10. This low-pressure liquid refrigerant further absorbs heat from the outside air in the outdoor heat exchanger 4, becomes a low-pressure gas refrigerant, and
It is returned to the compressor 3 through the gas pipe 13 and the suction pipe 14.

By continuing the above circulation cycle, the heat quantity absorbed by the refrigerant from the outside air in the outdoor heat exchanger 4 is transferred to the indoor heat exchanger 5
At that time, it is released into the indoor atmosphere and indoor heating is performed.

Next, the pump down operation will be described. First, from the above heating operation state, the solenoid valve 18 interposed in the first bypass pipe 17 is opened. Next, the gas closing valve 8 is operated to disconnect the first gas pipe 6 and the second gas pipe 7. Further shutoff valve
15 is operated to disconnect the third gas pipe 13 from the suction pipe 14 and to connect the second bypass pipe 19 to the suction pipe 14.
Further, the liquid shutoff valve 11 is operated to shut off the first liquid pipe 9 and the second liquid pipe 10 and to connect the first liquid pipe 9 and the second bypass pipe 19 to each other. By performing the above operation, the compressor 3
The discharge side piping system is closed in the outdoor unit 1 by the gas closing valve 8, the liquid closing valve 11 and the shutoff valve 15, and therefore the refrigerant discharged from the compressor 3 is in the outdoor unit 1. Will be enclosed in the heat exchanger 4 and the enclosed refrigerant will be cooled in the outdoor heat exchanger 4 and liquefied,
Mainly accumulated in the third gas pipe and the outdoor heat exchanger 4.

On the other hand, the third gas pipe 13 is installed in the suction side piping path of the compressor 3.
The first liquid pipe 9, the indoor heat exchanger 5, and the second gas pipe 7 communicate with each other through the second bypass pipe 19 to the suction pipe 14 blocked from the above. At this time, since there is no refrigerant inflow passage from the other pipe on the suction side of the compressor 3, the suction side of the compressor 3 functions exclusively for the suction of the refrigerant on the indoor unit 2 side. The refrigerant in the pipe is sucked into the suction side of the compressor 3 in a short time and discharged from the compressor 3 in the same manner as described above, and the outdoor heat exchanger 4 and the third gas pipe 13 are discharged.
It will be stored in the pipe with. In this way, the pump down ends when all the refrigerant on the indoor unit side is recovered.

As described above, the pipeline required for pump down is the pipeline for sending the refrigerant from the compressor 3 to the outdoor heat exchanger 4 through the first bypass pipe 17, and the refrigerant for the indoor unit 2 as the second bypass pipe. It is composed of a pipeline for collecting to the outdoor unit 1 side through 19, and therefore the compressor 3 acts exclusively for suction on the pipeline in the indoor unit 2, so that the refrigerant can be collected in a short time. Further, since the parts additionally provided for pump down are simple, the device can be constructed at low cost. Further, since the circuit configuration is relatively simple, the refrigerant can be smoothly circulated, and the pump down can be surely and easily performed.

Moreover, the gas closing valve 8, the liquid closing valve 11, the solenoid valve 18 and the first
Since the bypass pipe 17 is already installed for the defrosting operation, only the second bypass pipe 19 and the shutoff valve 15 need be additionally installed, and the device can be constructed at a lower cost. Further, in the above embodiment, since the shutoff valve 15 is constituted by a ball valve type three-way valve, the communication state of the third gas pipe 13, the second bypass pipe 19 and the suction pipe 14 during the heating operation and the pump down operation. Can be switched by an extremely simple operation.

Although the second bypass pipe 19 is connected to the liquid closing valve 11 in the above embodiment, it may be connected to the gas closing valve 8. The closing valve 8 or 11 on the side to which the second bypass pipe 19 is not connected may be a two-way opening / closing valve instead of a three-way valve. Further, in the above embodiment, the second bypass pipe
The switching valves 8 and 15 consisting of three-way valves were installed at the locations where 19 were connected, but each of the valves 8 and 15 was a two-way on-off valve, and the second bypass pipe 19 was the suction pipe 14 and the second liquid pipe 10. It is also possible to adopt a configuration in which an on-off valve is provided in the middle of the second bypass pipe 19 by connecting to the.

(Effects of the Invention) As described above, in the separate type air conditioner of the present invention, the refrigerant pipe in the indoor unit that is shut off from the outdoor unit by the gas closing valve and the liquid closing valve during the pump down operation is the outdoor unit. The third gas pipe connected to the heat exchanger is connected to the suction pipe of the compressor, which is blocked by the second opening / closing means, through the second bypass pipe, so that the suction force on the suction side of the compressor is the indoor heat exchanger side. It will function exclusively for refrigerant suction, and the suction pipe pressure will rapidly decrease as the amount of suction refrigerant on the indoor unit side decreases.
As a result, the suction force is further increased, so that the refrigerant on the indoor unit side can be recovered in a short time.

[Brief description of drawings]

FIG. 1 is a refrigerant piping system diagram showing an embodiment of the present invention, and FIGS. 2 (A) and 2 (B) are operation explanatory diagrams of a shutoff valve provided at a position II in FIG. FIG. 3 is a refrigerant piping system diagram in a conventional device. 1 ... outdoor unit, 2 ... indoor unit, 3 ... compressor, 4 ... outdoor heat exchanger, 5 ... indoor heat exchanger, 6 ...
First gas pipe, 7 ... Second gas pipe, 9 ... First liquid pipe, 10 ...
… Second liquid pipe, 11 …… Liquid shutoff valve, 13 …… Third gas pipe, 14…
… Suction pipe, 15 …… shutoff valve (second opening / closing means), 17 …… first bypass pipe, 18 …… solenoid valve (first opening / closing means), 19 ……
Second bypass pipe.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Katsuyuki Mizuno 2 at 1000 Otani, Okamoto-cho, Kusatsu City, Shiga Prefecture Daikin Industry Co., Ltd. Shiga Works (56) Reference JP-A-60-140053 (JP, A) Actual Open 54-142846 (JP, U) Actual open 57-160072 (JP, U)

Claims (1)

[Claims] 1. An outdoor unit (1) having a compressor (3), an outdoor heat exchanger (4) and an accumulator (16),
A separate type air conditioner in which a refrigerant circulation circuit is formed with an indoor unit (2) having an indoor heat exchanger (5), wherein the compressor (3) and the indoor heat exchanger (5) are connected to a first gas pipe. (6) is connected to the second gas pipe (7), a gas shutoff valve (8) is provided between the gas pipes (6) and (7), and the indoor heat exchanger (5) and the outdoor heat exchanger are connected. (4) is connected to the first liquid pipe (9) and the second liquid pipe (10), a liquid shutoff valve (11) is provided between both liquid pipes (9) and (10), and the outdoor heat exchange is performed. The compressor (4) and the suction port of the compressor (3) are connected by the third gas pipe (13) and the suction pipe (14) in which the accumulator (16) is interposed, and the third gas pipe (13) is connected. ) And a suction pipe (14) respectively, and a shutoff valve (15) is interposed between the first gas pipe (6) and the second liquid pipe (10) and a first opening / closing means (18) is provided. First viper A second bypass pipe (19) that is connected to the second gas pipe (7) or the first liquid pipe (9) and the suction pipe (14) and has a second opening / closing means (15). ) Separate air conditioner.