JPS6011788B2 - Multi-room air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a so-called multi-room air conditioner in which a plurality of indoor units are connected to one outdoor unit. The purpose is to provide.

Figure 1 shows a conventional multi-room air conditioner with outdoor unit 1.
Compressor 2, discharge muffler 3, four-way valve 4, heat source side heat exchanger 5, liquid side main pipe 6, liquid side branch pipes 7a, 7b, 7c, gas side branch pipes 8a, 8b, 8c, gas side main pipe 9, accumulator 10, a heating throttle mechanism 11 provided in the liquid side main pipe 6;
A check valve 12 is provided in parallel with the heating throttle mechanism 11 and on the side that blocks the flow of cold soot during heating, a heating throttle mechanism 1 in the liquid side main pipe 6, and a liquid side branch pipe 7a. ,7b,7c
A liquid receiver 14 provided between the branch part 13 of
15b, 15c, and connecting pipes 16a, 16b, which connect the indoor units 30a, 30b, 30c and the outdoor unit 1, which are provided at the ends of the liquid side branch pipes 7a, 7b, 7c.
Connection port 17a, 17b, 17c with 16c and solenoid valve 15
a, 15b, 15c, each liquid side branch pipe 7a, 7b, T
Derived from c, check valves 18a, 18b, 18c and throttle 1
A main bypass pipe 22 is formed by merging bypass pipes 20a, 20b, and 20c through serially connected pipes 9a, 19b, and 19c, respectively, and is connected to a low-pressure circuit 21 during heating operation, and a gas side branch pipe 8a, Reversible flow type solenoid valves 23a, 23b, 23c provided in each indoor unit 3 provided at the end of each gas side branch pipe 8a, 8b, 8c.
Connection ports 25a, 25b of connection pipes 24a, 24b, 24c connecting 0a, 30b, 30c and outdoor unit 1
, 25c, liquid receiver 14 and liquid side branch pipes 7a, 7b, 7c.
A three-way valve 26 provided in the liquid side main pipe 6 between the branch part 13, a three-way valve 27 provided in the main bypass pipe 22, and a branch part 28 between the four-way valve 4 and the gas side branch pipes 8a, 8b, 8c. It consists of a three-way valve 29 provided in the gas-side main pipe 9 between the four-way valve 4 and the compressor 2, and an accumulator 10 provided in the gas-side main pipe 9 between the four-way valve 4 and the compressor 2.

Moreover, each three-way valve 26, 27, 28 is connected to boats a and b, respectively.
．． Before the installation of the multi-room air conditioner, boat B and boat C are operated, boat a is closed, and boat a is closed off, and the air conditioner is controlled by a valve-like valve (not shown). After sealing the refrigerant, when operating the multi-room air conditioner, boat a and boat b are passed through the lotus and boat c is sealed, and the outdoor unit 1, indoor units 30a, 30b,
Let cold soot circulate through 30c. In addition, the indoor units 30a, 30b, 30c have user-side heat exchangers 31a, 31b, 31c, cooling throttle mechanisms 32a, 32, respectively.
b, 32c, check valves 33a, 33b, 33c provided in parallel with the cooling throttle mechanisms 32a, 32b, 32c so as to block the flow of cold soot during cooling operation, and connection piping 16
Connection ports 34a, 34b, 34c, 35a, 35 for connecting a, 16b, 16c, 24a, 24b, 24c
It consists of b, 35c.

The method of hemming work will be explained in the above-mentioned structure, but before that, the necessity of the bypass pipes 20a, 20b, and 20c will be explained.

Now outdoor unit 1 and indoor units 30a, 30b, 3
0c is connecting pipe 16a, 16b? 16c, 24a, 24
b, 24c and the respective three-way valves 26,
Boats 27 and 29, boat a and boat b, are in communication, boat c is closed, and the multi-room air conditioner is ready for operation.

Here, when one indoor unit 30a is in heating operation, the cold soot discharged from the compressor 2 is transferred to the indoor unit 30a in the discharge muffler 3, the four-way valve 4, the three-way valve 29, the branch part 28, and the gas side branch pipe 8a. The user-side heat exchanger 3 passes through the solenoid valve 23a, the connection port 25a, the connection pipe 24a, and the connection port 35a of the indoor unit 30a, whose passage is opened by operating the
It is liquefied in 1a, and the check valve 33a, the connection port 34a,
It passes through the connection pipe 16a, the connection port 17a of the outdoor unit, the tortoise valve 15a whose passage is opened by operating the indoor unit 30a, the branch 13, the three-way valve 26, and the receiver 1 basket, and then the heating throttle device 11. The pressure is reduced and the heat source side heat exchanger 5
It evaporates, passes through the four-way valve 4 and the storage tank 10 again, and returns to the compressor 2. At this time, since the indoor units 30b and 30c are stopped, the solenoid valves 23b and 15b and the indoor unit 30 for circulating soot to the indoor unit 30b are
Since the passages of the electromagnetic valves 23c and 15c for circulating cold soot to the indoor units 30b and 30c are closed, cold soot does not flow into the indoor units 30b and 30c. However, the solenoid valves 23b, 23c, 1
6b. Since the refrigerant 15c cannot completely close the flow of the refrigerant, the refrigerant gradually accumulates in the indoor units 30b and 30c. The amount of cold soot that accumulates in the stopped indoor units 30b, 30c is determined by the load on the outdoor unit 1 and the indoor unit 30a, the stopped indoor units 30b, 30c
The temperature of the user-side heat exchangers 31b, 31c and the positional relationship between the outdoor unit and the indoor units 30a, 30b, 30c vary greatly depending on the temperature, so the amount of refrigerant flowing through the indoor unit 30a that is being operated changes unstablely and cannot be adjusted properly. A proper refrigeration cycle will no longer be formed. Therefore, the bypass pipe 20
b, 20c allow the refrigerant accumulated in the indoor units 30b, 30c to be extracted to the low pressure circuit 21 during heating operation, making it possible to form an appropriate refrigeration cycle. In addition, when the two indoor units 30a and 30b are in heating operation, the solenoid valves 23a and 15a and the type solenoid valve 2
The passages 3b and 15h are opened, and the indoor units 30a,
Soot flows through the user-side heat exchangers 31a and 31b of 30b, and heating operation is performed.

Of the indoor units 30a and 30b currently in operation, when the operation of the indoor unit 30b is stopped, the cold soot that has been flowing through the user-side heat exchanger 31b of the indoor unit 30b is linked to the generation of indoor unit 30b. Since the solenoid valves 23b and 15b, which open and close the passage, close the passage, the solenoid valve 23b and the solenoid valve 1, including the user-side heat exchanger 31b,
It will be enclosed in the refrigeration cycle between 6b and 6b. In this way, the amount of soot accumulated in the refrigeration cycle including the indoor unit 30b is reduced by the above-mentioned indoor unit 3 when it is stopped.
0b, 30c, various conditions such as the load condition in which the indoor unit 30b was operating before being stopped, the solenoid valve 23b? 15b, the amount of refrigerant passing through the user-side heat exchanger 31a of the indoor unit 30a that is actually in operation may vary greatly or be extremely small. As a result, the heating capacity exhibited by the indoor unit 30a may become unstable, or a compressor may be imitated because an appropriate refrigeration cycle cannot be formed. In order to eliminate this problem, the bypass pipe 20b is used to transfer the cold butterflies accumulated in the user-side heat exchanger 31b of the indoor unit 30b to the low-pressure circuit 20 during heating operation.
The system is designed to ensure that a proper refrigeration cycle is formed under any conditions. As mentioned above, the bypass pipes 20a, 20b, and 20c play an important role.Next, we will explain the installation work.

Three-way valves 26, 27, 2 of outdoor unit 1 before hemming work
9 is ``Boat B and Boat C are in a state of connection, and Boat A is not compatible with Boats B and C.Then, the cold soot prefilled in the outdoor unit is released from each three-way valve 26,
27729's boat a side, that is, the compressor 2, the heat source side heat exchanger 5 "Liquid is accumulated in the receiver 14, etc. Now indoor unit 3
0a, 30b, 30c are the connecting pipes 16a,! 6b, 16
It is assumed that the outdoor unit 1 is connected to the outdoor unit 1 by the terminals c, 24a, 24b, and 24c. Here, the refrigeration cycle, that is, the liquid side branch pipes 7a, 7b on the boat b side of each three-way valve 26, 27, 29
, 7c, gas side branch pipes 8a, 8b, 8c, usage side heat exchangers 31a, 31b, 31c, connection pipes 36a, 16b, 1
In order to expel the air in 6c, 24a, 24b, 24c or to vacuum these refrigeration cycles, a solenoid valve 15 is used.
a; Open the passages of 15b, ISc, 23a, 23b, and 23c. First, in order to expel air from the refrigeration cycle on the boat b side of each three-way valve 26, 27, 29, the three-way valve 2
Each three-way valve 26, 27 of the outdoor unit turtle from boat c of 9
, 28, when the same cold soot is poured into the boat a side of the three-way valve 29, the cold soot passes through the boat b of the three-way valve 29 and splits into three directions at the branch part 28.
Solenoid valves 23a, 23b, 23c, connection piping 24a Tortoise 2
4b; 24c, user side heat exchanger 31a, 31b, 31
c "Check valves 33a, 33b, 33c, cooling throttle mechanism 3
2a, 32b, 33c, connection pipe 16a, vine 6b, 16
c, liquid side branch pipes 7a, 7b, 7c, solenoid valves 15a, 15b
, 15c, the branch part 13, and the three-way valve 26 of the boat b, and are discharged from the boat c. Also, liquid side branch pipes 7a, 7b, 7c
The cold butterfly diverted to the bypass pipes 20a, 20b, 20c from the middle of the check valves 18a, 18b? 18c, aperture 19a
, 19b, 19c, and the boat b of the three-way valve 27, and is discharged from the boat c. After the air has been expelled in this way, the boats c of the three-way valves 26, 27, and 29 are closed with caps (not shown), and the boats a and b of the three-way valves 26, 27, and 29 are allowed to pass through, and the boat c is blocked. Then, each three-way valve 2
The refrigeration cycles of boats 6, 27, and 29 on the boat a side and on the boat b side are connected and become ready for operation. Next, evacuation of the refrigeration cycle on the boat b side using the three-way valves 26, 27, and 29 will be explained. First, the boats c of the three-way valves 26 and 29 are each sealed with a cap (not shown), and the boat c of the three-way valve 27 is evacuated using a vacuum pump or the like.
Also in this case, the solenoid valves 15a, 15b, 15c, 23a?
If the passages 23b and 23c are left open, the bypass pipe 2
The air in the boat b section of the three-way valves 26 and 29, which is the farthest part from the three-way valve 27, can also be removed through the three-way valves 0a, 20b, and 20c. After the vacuum is drawn, each three-way valve 26,
If boats 27 and 29, boats a and b, pass through the lotus and boat c is blocked, the lotus rotation becomes possible. As mentioned above, the subordinate type multi-room air conditioner has bypass pipes 20a, 20b, 20.
c, in addition to the three-way valves 26 and 29 provided in the liquid-side main pipe 6 and gas-side main pipe 9, another three-way valve 27 is required in the main bypass pipe 22, resulting in high cost. Another drawback is that the three three-way valves 26, 27, and 29 must be operated during installation, making the construction time-consuming.

-The present invention eliminates the above-mentioned drawbacks.The present invention will be explained below with reference to the accompanying drawings showing one embodiment of the present invention. The valve will be explained based on FIG. 2.The thermoelectric expansion valve 40 has a valve portion 41.
and a valve driving portion 42. Valve part 411 and valve frame 43
and a valve body 44. The valve frame 43 is provided with a valve seat portion 45 and has an inflow boat 46 and an outflow boat 47 from which fluid flows out, and each boat 46 and the outflow boat 7 are provided with a medium pipe 48,
Q9 is connected. The valve body 44 has two upper and lower members 50 and 51 connected to each other, and in these members 58 and 51, passages 52 and 53 are formed for transporting the outflow boat 47 side and the inside of the valve driving portion 42. A check valve 54 is provided between the passages 52 and 53 to prevent soot from flowing from the passage 53 to the passage 52. The valve body 44 is provided in a hole 55 formed in the valve frame 43 so as to be able to move vertically. On the other hand, the valve driving portion 42 includes a space 5 sealed by an upper casing 56, a lower casing 57, and a valve frame 43.
8 is formed. Two bimetals 59 and 60 are housed in this space 58, and both bimetals 69 and 6
0 are arranged in parallel at both ends with spacers 61 and 62 interposed therebetween. Then, holes 63 and 64 are bored in the center of both bimetals 59 and 60, and a support pin 65 fixed to the center of the inner surface of the upper casing 56 is inserted from above into the hole 63 of the upper bimetal 59. By inserting a pin portion 66 formed at the upper end of 44 into the hole 64 of the lower bimetal 60 from below, both upper bimetals 59 and 6M are supported within the space 58. Note that the valve body 44 is always urged upward by a spring 68 via the seat 67. 69 is an electric heater for forcibly heating the upper bimetal 59, and is wound around the upper bimetal 59.

Terminals 70 and 71 are connected to both ends of the electric heater 69 and are provided through the upper casing 56.

This upper bimetal 59 is forcibly heated by an electric heater 69 so that both ends thereof are directed upward (in the direction of arrow A in the figure).
It transforms so that it moves. Therefore, when the electric heater 69 is energized, the upper bimetal 59 is deformed, and the spring body 8 pushes up the valve body 44, opening the space between the valve seat 4 and the lower end of the valve body 44. That is, the valve is opened. The degree of opening of the valve in this case is adjusted by the amount of power supplied to the electric heater 69. That is, if a large voltage is applied, the upper bimetal 59 will be greatly deformed and curved, and the valve resistance will increase. Conversely, when the voltage applied to the electric heater 69 is small, the amount of deformation of the upper bimetal 59 is small, and the degree of valve interaction is small. The lower bimetal 60 is a bimetal for compensating for load conditions, and is deformed by the temperature influence of the soot flowing into the space 58 from the sliding surface between the hole 55 and the valve body 44 and the ambient air temperature. . In addition, this thermoelectric expansion valve 40
'Well, it's a forward/reverse flow type expansion valve, and the cold soot flows into the inflow boat 4.
6, flows through the constriction formed between the valve body 44 and the valve seat 45, and flows out from the outflow port 47. , the flow can also flow out from the inflow boat 46 through a constriction formed between the valve body 44 and the valve seat 45. In this case, due to the shape of the valve, the flow flows from the inflow boat 46 toward the outflow boat 47. If the degree of restriction is the same for flowing soot as compared to the opposite flow, the flow resistance of cold soot will be slightly lower by 4. In addition, if the inflow boat 46 side is high pressure and the outflow boat 47 side is low pressure. In this case, a part of the refrigerant flows into the space 58 from the sliding surface between the valve body 44 and the hole 55, but the cold soot that has flowed in flows through the passages 52, 53 and the check valve 54 and flows out of the boat. 47 and does not accumulate in the space 58. Conversely, when the pressure on the outflow boat 47 side becomes higher than that on the inflow boat 46 side, the check valve 54 closes and soot flows into the space 58. Next, an embodiment of the multi-chamber air conditioner according to the present invention will be described with reference to FIG. Heat exchanger 85, liquid side main pipe 86, liquid receiver 87, and liquid side branch pipes 88a, 88b.8 created by branching the liquid side main pipe 86 into the number of indoor units.
8c, thermoelectric expansion valves 40a, 40b, 40c provided in the liquid side branch pipes, bidirectional solenoid valves 91a, 91b, 91c, respectively, are interposed, and each indoor unit 95a
, 95b, 95c branch pipes 92 on the gas side.
a, 92b, 92c This gas side branch pipe 92a. 92b,9
It consists of a gas side main pipe 93, an accumulator 94, etc., which are formed by merging two gases. In addition, each liquid side of the outdoor unit 81, gas side branch pipes 88a, 88b, Todoroki 8c7 92a, 9
Indoor units 95a each connected to 2b and 92c
, 95b, 96c are user-side heat exchangers 96a, 3, respectively.
It consists of 6b, 96c, etc. Now, the operation during cooling operation in this configuration will be explained. First, it is assumed that one indoor unit 95a is being operated. The cold soot gas discharged from the compressor 82 passes through a discharge muffler 83 and a four-way valve 84, is liquefied in a heat source side heat exchanger 85, and is sent to a liquid receiver 87 via a liquid side main pipe 86. The liquid-cooled soot exits the liquid receiver 87, passes through the thermoelectric expansion valve 40a in the liquid-side branch pipe 88a, becomes a low-pressure liquid, goes to the user-side heat exchanger 96a of the indoor unit 95a, evaporates, becomes gaseous, and is energized to close the valve. It returns to the compressor 82 via the open bidirectional solenoid valve 91a, the gas side branch pipe 92a, the four-way valve 84, and the accumulator 94. At this time, since the indoor units 95b and 95c are stopped, no fin pressure is applied to the heat dew expansion valves 40b and 40c, so the valve portions are closed and no refrigerant is allowed to flow. Also, bidirectional solenoid valve 91
If b and 91c are opened, the thermal turtle type expansion valves 40b and 40
The cold soot that leaks from the indoor units 95b and 95c and tends to accumulate in the idle indoor units 95b and 95c can be extracted to the low-pressure part, that is, the gas side main pipe during cooling operation, and a normal refrigeration cycle can be formed. When the indoor unit 95a is operated in this way, if a control device is provided that can change the voltage applied to the thermoelectric expansion valve 40a depending on the load condition of the indoor unit 95a, the flow rate of the refrigerant can be freely controlled. can be changed. Therefore, extremely comfortable air conditioning can be achieved just by continuously changing the function of the thermoelectric expansion valve 40a while the compressor 82 is kept in continuous operation. Next, when the indoor units 95b and 95c are additionally operated while the room in which the indoor unit 95a is installed is sufficiently cooled, the thermoelectric expansion valves 40b and 40c and the bidirectional solenoid valve 9
1b and 91c are energized, and the refrigerant flows through the indoor units 95b and 95c.

Now, each indoor unit 95a, 95b, 95c is
, 94b, 95c thermoelectric expansion valves 40a, 40b, 4
Suppose that the voltage is controlled so as to open the relationship 0-c, and the air conditioning load in the room where the indoor units 95b and 95c are installed is much larger than the air conditioning load in the room where the indoor unit 95a is installed. , thermoelectric expansion valves 40b, 40c
A large voltage is applied to the thermoelectric expansion valve 40a, so that the valve is fully opened.On the other hand, a very large voltage is not applied to the thermoelectric expansion valve 40a, and the valve function becomes small. Therefore, a large amount of cold soot flows through the indoor units 95a and 95c, and air conditioning is performed in accordance with the load of the room. Next, the operation during heating operation will be explained.

First, it is assumed that the indoor unit 95al is being operated.
The cold soot gas discharged from the compressor 82 is sent to the discharge muffler 83.
, the four-way valve 84, the gas side branch pipe 92a, and the indoor unit 95a through the bidirectional solenoid valve 91a where voltage is applied and the valve is opened.
It is liquefied in the utilization side heat exchanger 96a. This liquefied cold soot is then passed through a 4-oa thermoelectric expansion valve to which a voltage is applied.
It becomes a low-pressure liquid, passes through the liquid side branch pipe 88a, the liquid receiver 87, and the traverse side main pipe 86, evaporates in the heat source side heat exchanger 8-5, and passes through the four-way valve 84 and accumulator 94 to the compressor 8.
Return to 1. Now here thermoelectric expansion valves 40a, 40b, 4o
C is a type that allows the flow of refrigerant in the opposite direction to the flow of refrigerant during cooling, and functions as an expansion valve in the same way as in the case of refrigerant. Therefore 1
Since one thermoelectric expansion valve can perform both the throttling action during cooling and the action during heating, it is cheaper than a type that uses dedicated expansion valves for cooling and heating, and it takes less space to store the expansion valve. The space is small. Also, the gas side branch pipe 92b to which the indoor units 95b and 95c that are inactive are connected,
If the electromagnetic valves 91b and 91c in the indoor units 92c are closed and a voltage is applied to the thermoelectric expansion valve in the liquid side branch pipe and the valve part is opened, the user side heat exchanger 96b in the indoor units 95b and 95c,
96c is operated at a low pressure during heating operation, so that soot does not accumulate in the user-side heat exchangers 96b and 96c. Therefore, unlike the conventional multi-room air conditioner, there is no need for a bypass circuit for removing soot from the idle indoor unit during heating operation, resulting in lower costs and space savings. In addition, the operation of the thermoelectric expansion valve during operation of heating one room and operation of two or more rooms can be considered in the same way as during operation of cooling. By controlling the valve darkness, it is possible to send the required amount of cold soot to each indoor unit. Here I will explain the hemming work. Before the porridge making work, the three-way valves 98 and 99 of the outdoor unit 81 are in a state where boats B and C are connected to each other, and boat A is not connected to boats B and C. The soot previously filled in the outdoor unit 81 is transferred to the refrigeration cycle on the boat a side of each three-way valve 98, 99, that is, the compressor 82, the heat source side heat exchanger 85,
It accumulates in the liquid receiver 87, etc. Now indoor unit 95a, 9
5b and 95c are connected to the outdoor unit 81 through connection pipes 90a, 90b, and 90c. Here, the refrigeration cycle on the boat b side of each three-way valve 98, 99, that is, the liquid side branch pipes 88a, 88b, 88c, and the gas side branch pipes 92a, 92b.
, 92c, the use-side heat exchangers 96a, 96b, 96c, and the connecting pipes 90a, 90b, 90c to expel the air or to vacuum these refrigeration cycles, the forward and reverse flow type thermoelectric expansion valves 40a, 40b, 40c. Solenoid valve 91a, 9
Open the passages 1b and 91c. First, each three-way valve 98,9
In order to expel air from the refrigeration cycle on the boat b side of 9, it is necessary to remove air from the boat c of the three-way valve 98 to each three-way valve 9 of the outdoor unit 81, and the same lined soot as the refrigerating chamber sealed on the boat a side of 99. When poured, the medium passes through the boat b of the three-way valve 98, and the gas side branch pipe 92a; 92b, g2c; Liquid side branch pipes 92a, g2b
, 92c, solenoid valve flea turtle ag glb, 99c ~ three-way valve 9
It passes through port b of 9 and is released from boat c.

After the air has been expelled in this way, the boats c of the three-way valves 98 and 89 are closed with caps (not shown).
When Crab 9's boat a and boat P are passed through and boat c is closed, the refrigeration cycles of boat a and boat c of each three-way valve 9 & gg are connected and become ready for operation.Subsequently, three-way valve 987 The evacuation of the refrigeration cycle on the boat b side of horse mackerel 9 will be explained.

First, the boat c of the three-way valve base 8 is sealed with a cap (not shown), and the boat c of the three-way valve 9g is evacuated using a vacuum pump. In this case, if the passages for the forward and reverse flow type thermoelectric expansion valves 48a, 48c and the solenoid valves a, b and SSc are opened, the three-way valve located farthest from the three-way valve 9, The air in the boat b section of the valve 99 can also be removed.
After the vacuum has been drawn, boats A and B of each three-way valve 99 are allowed to pass through each other, and boat C is sealed off, and the boat is ready for operation. Although the air was expelled from the refrigeration cycle in the direction from the three-way valve 98 to 99, it is also possible to expel the air from the three-way valve 99 toward S8.

Also, in the case of evacuation, the three-way valve 991 and a vacuum pump are connected to perform evacuation, but conversely, a vacuum pump may be connected to the three-way valve 98 to perform evacuation. Further, a forward and reverse flow type thermoelectric expansion valve 48Tsuru Tortoise fin b94Qc is a type that opens the passage when the current is not energized, contrary to the one described above.Furthermore, a three-way valve G9 is used as the solenoid valves 91a, 91b, 9Tortoise c. If you choose a type that allows flow only in the side direction even when the current is not energized, you can use the forward and reverse flow thermal crab-shaped expansion valve 40.
a, Tortoise Qb, 40c and solenoid valve gia; 91b, 9 Tortoise c do not have to be energized to open the passage, but when creating air, air is expelled from the three-way valve 98 to the three-way valve 99, and when vacuuming. Vacuum can be drawn from the three-way valve 99.

Furthermore, in the present invention, as in the conventional example, the bypass pipes 20a, 20
b, 20c are no longer required, so the cost is lower because only two three-way valves are required, and the time and effort required to operate the three-way valve is eliminated.Furthermore, since there is a restriction in the bypass pipe as in the conventional example, the air flow is reduced. There is also no drawback that it takes time to expel or vacuum.

As mentioned above, the multi-room air conditioner according to the present invention uses a forward-reverse flow type thermoelectric expansion valve, eliminates the need for bypass pipes, and simplifies the pipe lines, resulting in "lower costs" and easier installation work. There are fewer 3-way valves to operate, which means less construction effort is required, and air can be expelled or vacuumed in a short period of time. Because of this, it has many advantages, such as being simpler and less likely to make mistakes, compared to conventional systems, which have complicated procedures for evacuation and evacuation of air.

[Brief explanation of the drawing]

Fig. 1 is a refrigeration cycle diagram of a conventional multi-chamber air conditioner, Fig. 2 is a sectional view of a thermoelectric expansion valve used in a multi-chamber air conditioner according to an embodiment of the present invention, and Fig. 3 is a sectional view of a thermoelectric expansion valve used in a multi-chamber air conditioner according to an embodiment of the present invention. It is a refrigeration cycle diagram of a room air conditioner. 2, 8 states...The compressor is also turtle, 84...Four-way valve 5, crab turtle...
... Are the heat source side heat exchangers also 31a and 31b? 3 heads c, 9
689 96ne, 96c...The heat exchanger on the user side is also Kame Q, &
Haa, mother Qb, 48c...'thermoelectric expansion valve, 2fu basket? 9 29; 98, 99... Three-way valve. Traditional illustration 1 scale scale 3 illustration Tsutomu 2 illustration

Claims (1)

[Claims] 1. A single outdoor unit consisting of a compressor, a four-way valve, a heat exchanger on the heat source side, etc. is connected to multiple indoor units consisting of heat exchangers on the user side, etc. via connecting piping, and the main pipes on the liquid side and the gas A three-way valve is provided in each of the side main pipes, a forward-reverse flow type thermoelectric expansion valve is provided in each of a plurality of liquid side branch pipes branched from the liquid side main pipe, and the opening degree of the thermoelectric expansion valve is controlled by the air conditioning of the indoor unit. A multi-room air conditioner with a configuration that changes according to the load.