JPS602536Y2 - Multi-room cooling system - Google Patents

Description

[Detailed description of the invention] The present invention improves the refrigerant flow rate control performance of the pressure reduction mechanism when a capillary tube is used as a pressure reduction mechanism, and also prevents the refrigerant drift that tends to occur during full room operation and improves liquid return. The present invention aims to provide a multi-room cooling device that can solve the problem of cooling.

There are cooling devices that connect multiple indoor units to one outdoor unit and use capillary tubes for the pressure reducer in order to provide the device at low cost. While there is a difference in the amount of refrigerant required for single-chamber operation and dual-chamber operation,
Since the control performance of the capillary tube is fixed, there is a problem in that there is an excess or deficiency of refrigerant and stable operation cannot be obtained.

As a solution to this problem, a cooling device as shown in FIG. 2 is known from Japanese Patent Publication No. 52-18945, etc.
capillary 10a' between ta/, 1 lb'
tIO'b is provided, and each capillary tube 10
A bypass pipe 12 connecting branch pipes in parallel is provided between a'9 10b' and each on-off valve 11a'ilb' to reduce the amount of pressure reduction in the refrigeration cycle system during one-chamber operation and two-chamber operation. It is adjustable.

However, this device has the following shortcomings.

In other words, each branch point on the inflow side of the high-pressure branch pipe is a part that allows the refrigerant to flow in a liquid-gas mixed state, so during two-room operation, the degree of load differs between each indoor unit, resulting in differences in operating conditions. If there is a difference in the installation condition due to the length of the piping or the difference in height of the installation location, an unbalanced resistance will occur in the refrigerant system of both units, and as a result, the refrigerant with low resistance will be This is undesirable because it causes a phenomenon where more refrigerant liquid flows in one direction, causing the liquid to return to the compressor and reducing the performance of the device.

In view of the fact that conventional cooling devices have had various problems, the present invention has developed a new cooling device that can fundamentally eliminate the above-mentioned defects and can also reduce costs. The company devised this system, and its characteristics are two branch pipes each equipped with a capillary tube corresponding to each of the two indoor units and an on-off valve installed on the outlet side of the capillary tube. For this purpose, a bypass pipe is provided to connect the branch pipes between each of the capillary tubes and each on-off valve to enable communication between the inlets of each on-off valve, and to connect two chambers simultaneously to this bypass pipe. The structure includes an on-off valve that is closed during operation and opened during single-chamber operation, and a capillary tube for adjusting the amount of refrigerant during single-chamber operation.

Hereinafter, the content of the present invention will be explained in detail with reference to embodiments shown in the drawings.

In FIG. 1, 1 is an outdoor unit, and 2a and 2b are indoor units.The outdoor unit 1 is composed of a compressor 3, a condenser 4, a pressure reducing mechanism 5, and an accumulator 6, while the indoor units 2a and 2b are Each of the evaporators 8a and 8b includes an indoor fan (not shown).

The pressure reducing mechanism 5 provided in the high pressure liquid pipe 7 of the outdoor unit 1 branches the liquid pipe 7 into branch pipes 9a and 9b corresponding to the number of indoor units 2a and 2b, and each of the branch pipes 9a
, 9b are provided with on-off valves 11a, llb such as electromagnetic valves, respectively, and capillary tubes 10a, 10b are interposed between the branch point 15 and each on-off valve 11a, 11b, respectively. A bypass pipe 12 is provided between each of the on-off valves 11a and llb to connect the branch pipes 9a and 9b in parallel, and an on-off valve such as a solenoid valve 13 and a capillary tube 14 for adjusting the amount of refrigerant are installed in this bypass pipe 12. It has an interposed structure.

The capillary tubes 10a and 10b are the main pressure reducers for controlling the refrigerant in correspondence with each indoor unit 2ay2b, and they are suitable for, for example, all-room operation when the indoor units 2a and 2b are operated simultaneously. The amount of pressure reduction shared by each unit is set to an appropriate value so that the indoor units 2a, 2
It goes without saying that if b has the same capacity, the amount of pressure reduction will be the same, taking into account the capacity of the outdoor unit 1.

On the other hand, in the capillary tube 14, when only one indoor unit 2a or 2b is operated in one room, a resistance circuit in which the capillary tube 10b or 10a and the capillary tube 14 are connected in series is connected in parallel to the capillary tube 10a or 10b. It is set to an appropriate value so that the amount of refrigerant can be controlled to the optimum amount by entering the connected state.

When performing cooling with the cooling device configured as described above, in order to operate two units under conditions where the amount of charged refrigerant is set to be optimal for two unit operation, the on-off valve 13 should be closed and the compressor 3 should be driven. Then, the high-temperature, high-pressure refrigerant gas discharged from the compressor 3 exchanges heat with the outside air in the condenser 4 to become a high-pressure liquid refrigerant, which is divided into branch pipes 9a and 9b, and then flows into the capillary tube 10a.
, 10b, and then reach the evaporators 8a, 8b of the indoor units 2a, 2b through the on-off valves 11a, llb, where they absorb heat from the indoor air and evaporate, becoming refrigerant gas and flowing through the low-pressure gas pipes 16... After passing through the accumulator 6, the air is sucked into the compressor 1.

In this way, simultaneous cooling of the two rooms is performed, but since the on-off valve 13 of the bypass pipe 12 is closed as described above, the refrigerant bypass phenomenon in the bypass pipe 12 does not cause any heat, and both indoor units) 2a, 2b is the high pressure liquid pipe 7 and the intake gas pipe 16
Each unit forms an independent refrigerant flow path between the units 2a and 2b, so that mutual interference due to resistance imbalance between the two units 2a and 2b, that is, the phenomenon of drifting, does not occur.
, 2b, the refrigerant is divided in accordance with the load, so there is no shortage of capacity, and liquid return can be prevented.

Next, in the case of individual operation in which only room 1 of the two rooms is operated, for example, one indoor unit 2a is operated by opening the on-off valve 11a, and the other indoor unit 2b is operated with on-off valve 11a.
1b is closed to stop the operation and perform -chamber operation, by opening the on-off valve 13 of the bypass pipe 12, the refrigerant liquid that has passed through the condenser 4 is divided into branch pipes 9a and 9b, and the capillary tube After the refrigerant depressurized in step 10a and the refrigerant depressurized in the series resistance circuit of capillary tube 10b and capillary tube 14 join together, they pass through on-off valve 11a and reach evaporator 8a of indoor unit 2a, where they are evaporated and vaporized. Thereafter, it is sucked into the compressor 3 via the accumulator 6.

In this case, the refrigerant is transferred to the capillary tube 10a.
By making a single resistance circuit and a series resistance circuit consisting of capillary tubes 10b and 14 flow in parallel, the resistance is halved, the amount of refrigerant flowing into the evaporator 8a is increased, and the degree of superheating of the refrigerant at the outlet of the evaporator 8a is reduced. The rise in discharge temperature can be suppressed without increasing the temperature excessively.

Of course, there is no problem of uneven flow of the refrigerant during single room operation.

In the embodiment described above, each indoor unit 2at2b.
Each capillary tube 10a, 10 corresponding to...
b... is not limited to a single structure as shown in the example shown, but it is divided into two parts and one of them is connected to the indoor unit 2.
It is also possible to interpose the evaporators 8a, 8b, . . . in series on the inlet side of each of the evaporators 8a, 8b, . , such modifications are also included in the red book invention.

The device of the present invention has the above structure and function, and is used in a multi-room cooling device in which two indoor units 2a and 2b are connected in parallel to one outdoor unit 1. 7 is branched to each indoor unit 2a, 2b to form branch pipes 9a, 9b, and these branch pipes 9a, 9
On-off valves 11a and llb are provided in b, respectively, and the branch pipe 9a
, 9b and each of the on-off valves 11a, 11b, respectively, and each of the branch pipes 9a between each of the capillary tubes 10a, 10b and each on-off valve 11a, 11b. , 9b are provided with a bypass pipe 12 that communicates with each other, and the bypass pipe 1
2, a configuration in which an on-off valve 13 that is closed during simultaneous operation of two chambers and opened during operation of one chamber, and a capillary tube 14 for adjusting the amount of refrigerant during operation of one chamber; Therefore, it becomes possible to automatically adjust the difference in the amount of refrigerant circulation between the one-chamber operation and the two-chamber operation using the capillary tubes 10a, 10b, and 14, and maintain the amount at an appropriate level.

Moreover, in the case of two-chamber operation, unfavorable flow bias caused by the bypass pipe 12 can be easily prevented by simply closing the on-off valve 13, and as a result, insufficient capacity in one indoor unit can be prevented. In the other indoor unit, inconveniences such as wet operation are eliminated, and an excellent effect of maintaining stable cooling operation with a sufficiently large capacity is achieved.

In addition, if you are planning to purchase more units in the future and are installing one indoor unit and operating it, or if you are installing two indoor units and operating only one unit, you can operate it without any problems. It can meet the needs of customers and has excellent features in terms of sales promotion.

[Brief explanation of the drawing]

Figure 1 is a refrigeration circuit diagram of one example of the cooling device of the present invention;
The figure is a refrigeration circuit diagram of a conventional cooling device. 1...Outdoor unit, 2a, 2b...
Indoor unit, 7... High pressure liquid pipe, 9a, 9b.
...Branch pipe, 10a, 10b...Capillary tube, 11a, llb...Opening/closing part,
12...Bypass pipe, 13...Opening/closing valve, 14...Capillary tube for adjusting the amount of refrigerant.

Claims (1)

[Scope of utility model registration request] Two indoor units 2a and 2b are combined into one outdoor unit 1
In the multi-room cooling device connected in parallel to each other, the high-pressure liquid pipe 7 is branched to each of the indoor units 2at2b to form branch pipes 9a and 9b, and each branch pipe 9a and 9b is provided with an on-off valve 11a, 11b are provided respectively, and each of the branch pipes 9a, 9
Capillary tubes lea and 10b are provided between the branch point 15 of b and each of the on-off valves 11a and llb, respectively, and each of the branch pipes is provided between each of the capillary tubes 10a and 10b and each of the on-off valves 11a and llb. 9ay9
b A bypass pipe 12 that communicates with each other is provided, and the bypass pipe 12 has an on-off valve 13 that is closed when two rooms are operated simultaneously and opened when one room is operated, and an on-off valve 13 that adjusts the amount of refrigerant during one room operation. A multi-room cooling device characterized by interposing a capillary tube 14 for cooling.