JPS6327622B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a multi-room air conditioning type air conditioner. This type of air conditioner is equipped with two indoor heat exchangers, for example, and air-conditions two rooms at the same time by simultaneously flowing refrigerant through these indoor heat exchangers, or by supplying refrigerant to one indoor heat exchanger. By flushing, only one room is air-conditioned.

By the way, when air conditioning only one room, the capacity of the compressor may be small, so in this case, a portion of the refrigerant gas is released from the cylinder of the compressor to the release pipe.

However, in the past, the release tube was opened and closed by a solenoid valve, which resulted in high cost and high power consumption, making it uneconomical.

The present invention has been made focusing on the above circumstances,
The purpose is to provide an air conditioner that can release refrigerant without using a solenoid valve, thereby reducing cost and power consumption.

An embodiment of the present invention will be described below with reference to FIG. FIG. 1 shows a refrigeration cycle of a multi-room air conditioner, in which 1 is a compressor. This compressor 1 is connected to an outdoor heat exchanger 3 via a refrigerant pipe 2.
is connected. Furthermore, a parallel circuit A in which the first and second indoor heat exchangers 5 and 6 are connected in parallel is connected between the refrigerant suction side of the compressor 1 and the refrigerant outlet side of the outdoor heat exchanger 3. has been done. In this case, the first indoor heat exchanger 5 and the second indoor heat exchanger 6 are installed in separate indoor units, and these two sets of indoor units are installed in separate rooms. It is becoming more and more common. Further, a first on-off valve 7 is disposed on the connection end side of the refrigerant outflow side of the outdoor heat exchanger 3 in one branch pipe 4a of the parallel circuit A, and a first on-off valve 7 is connected to the first on-off valve 7 on the first indoor side. A capillary tube (pressure reducer) 8 is disposed between the heat exchanger 5 and the heat exchanger 5.
A second on-off valve 9 is connected to the refrigerant outflow side of the outdoor heat exchanger 3 in the other branch pipe 4b of the parallel circuit A, and a second on-off valve 9 is connected to the second indoor heat exchanger 3. Capillary tubes (pressure reducers) 10 are arranged between the exchangers 6 and the exchangers 6, respectively. When two sets of indoor units are operated simultaneously, the first on-off valve 7 and the second on-off valve 9 are each held open, and only one of the two sets of indoor units is operated. When the indoor unit is operated and the other indoor unit is held in a stopped state, for example, when the indoor unit on which the first indoor heat exchanger 5 is installed is operated, the indoor unit in this operating state is The first on-off valve 7 on the unit side is in the open state, and the second on-off valve on the indoor unit side is in the stopped state.
The on-off valve 9 is maintained in a closed state.

In addition, a release pipe 11 is provided in the cylinder of the compressor 1.
One end side of is connected. This release tube 11
Release branch pipes 12a and 12b are connected to the other end. In this case, the other end of one release branch pipe 12a is connected to one branch pipe 4a of parallel circuit A.
The other end of the other release branch pipe 12b is connected between the first on-off valve 7 and the capillary tube 8 in the parallel circuit A, and the other end of the other release branch pipe 12b is connected between the second on-off valve 9 in the other branch pipe 4b of the parallel circuit A. and the capillary tube 10, and these release tubes 11 and release branch tubes 12a, 12
b forms a release circuit B that releases a part of the refrigerant in the cylinder of the compressor 1. Furthermore, check valves 13 and 14 are provided in each of the release branch pipes 12a and 12b, respectively, to prevent the refrigerant from flowing back from the inside of each of the branch pipes 4a and 4b to the cylinder side of the compressor 1.

Next, the operation of the above configuration will be explained. First, during simultaneous air conditioning of two rooms in which two sets of indoor units are operated simultaneously, the first on-off valve 7 and the second on-off valve 9 are each held open. In this case, the refrigerant gas discharged from the compressor 1 is condensed in the outdoor heat exchanger 3 as shown by the dotted arrow in FIG. 4a and 4b, respectively. The refrigerant liquid introduced into both branch pipes 4a and 4b is depressurized within capillary tubes 8 and 10, and then introduced into first and second indoor heat exchangers 5 and 6. Furthermore, these first and second
Refrigerant gas evaporated by heat exchange with indoor air in the indoor heat exchangers 5 and 6 is sucked into the compressor 1. In this case, the pressure on the discharge side of the compressor 1 is Pa,
When the pressures in the branch pipes 4a and 4b are Pb and Pc, and the pressure in the release pipe 11 is Pd, Pd<PcPbPa. Therefore, in this case, the release tube 11
Since the refrigerant on the side is not released into the branch pipes 4a and 4b, the entire refrigeration cycle is maintained in a high-capacity operating state.

On the other hand, if only one of the two indoor units is operated and the other indoor unit is held in a stopped state, for example, the side to which the first indoor heat exchanger 5 is attached When the indoor unit is operated, the first on-off valve 7 on the indoor unit side in the operating state is kept open, and the second on-off valve 9 on the indoor unit side in the stopped state is kept closed. In this case, the refrigerant gas discharged from the compressor 1 is condensed in the outdoor heat exchanger 3 as shown by the solid arrow in FIG. It is introduced only to the piping 4a side. The refrigerant liquid introduced into the branch pipe 4a is depressurized in the capillary tube 8 and then introduced into the first indoor heat exchanger 5. After being evaporated by heat exchange with indoor air, this refrigerant gas is sucked into the compressor 1. In this case, if the suction pressure of the compressor 1 is Pe, then Pa>Pd>Pe, and PbPd, PcPe. Therefore, in this case, the refrigerant released from the cylinder of the compressor 1 to the release pipe 11 side is introduced into the branch pipe 4b from the release branch pipe 12b via the check valve 14, and the refrigerant in the branch pipe 4b is further introduced into the branch pipe 4b. Since the release operation is performed in which the refrigerant is sucked into the compressor 1 through the pillar tube 10 and the second indoor heat exchanger 6 in sequence, the amount of refrigerant circulated in the main circuit of the refrigeration cycle is reduced, and the refrigerant can be operated in a low-capacity operating state. Retained.

Therefore, in the case of the above configuration, parallel circuit A
As the first on-off valve 7 and second on-off valve 9 interposed in both branch pipes 4a, 4b are opened and closed, the pressure in each branch pipe 4a, 4b and the pressure in release circuit B increases. Since the pressure difference between the compressor 1 and the refrigerant release from the cylinder of the compressor 1 is controlled, there is no need to provide a special electromagnetic valve for controlling the refrigerant release as in the conventional case. Therefore,
Since the refrigerant can be released without using an expensive solenoid valve, it is possible to reduce costs and power consumption.

Note that the present invention is not limited to the above-mentioned embodiment, and as shown in FIG. A gas injection system may be used, in which the gas injection system is connected to the gas injection pipe 23 by an injection pipe 23 equipped with an on-off valve 22.

Incidentally, the same parts as in the above embodiment are given the same numbers and the explanation thereof will be omitted.

Further, in the above-described embodiment, a two-chamber air-conditioning type was shown, but the present invention is not limited to this, and even if it is an air-conditioning type with three or more chambers, the same effects as described above can be obtained.

As explained above, the present invention connects a parallel circuit in which a plurality of indoor heat exchangers are connected in parallel between the refrigerant suction side of the compressor of the refrigeration cycle and the refrigerant outlet side of the outdoor heat exchanger. In each branch pipe of this parallel circuit, an on-off valve is provided on the connection end side with the refrigerant outflow side of the outdoor heat exchanger, and a pressure reducer is provided between this on-off valve and each indoor heat exchanger. ,
One end of the release pipe is connected to the cylinder side of the compressor, and a release branch pipe is connected to the other end of the release pipe, and the other end of each release branch pipe is connected between the on-off valve and pressure reducer in each branch pipe. A release circuit is provided, and a check valve is installed in each release branch pipe to prevent the refrigerant from flowing back from the inside of each branch pipe to the cylinder side of the compressor. By opening and closing the interposed on-off valve, the pressure difference between the pressure in each branch pipe and the pressure in the release circuit can be controlled, and the release of refrigerant from the cylinder of the compressor can be controlled. Therefore, it is not necessary to use an electromagnetic valve as in the conventional case, and it is possible to reduce costs, and there is an effect that it is economical because no electric power is required.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing a refrigeration cycle according to one embodiment of the present invention, and FIG. 2 is a schematic diagram showing a refrigeration cycle according to another embodiment. 1...Compressor, 3...Outdoor heat exchanger, A...
Parallel circuit, 4a, 4b...branch piping, 5...first
indoor heat exchanger, 6... second indoor heat exchanger, 7, 9... on-off valve, 8, 10... capillary tube (pressure reducer), 11... release tube, 12
a, 12b... Release branch pipe, 13, 14...
Check valve, B...Release circuit.

Claims (1)

[Claims] 1 A parallel circuit in which a plurality of indoor heat exchangers are connected in parallel is connected between the refrigerant suction side of the compressor of the refrigeration cycle and the refrigerant outlet side of the outdoor heat exchanger, and each branch pipe of this parallel circuit is An on-off valve is disposed at the end connected to the refrigerant outflow side of the outdoor heat exchanger in the interior, and a pressure reducer is disposed between the on-off valve and each of the indoor heat exchangers, and one end is connected to the compressor. A release branch pipe is connected to the other end of the release pipe connected to the cylinder side of the machine, and the other end of each release branch pipe is connected between the on-off valve and the pressure reducer in each branch pipe. An air conditioner characterized in that a release circuit is provided, and check valves are provided in each of the release branch pipes to prevent backflow of refrigerant from the inside of each of the branch pipes to the cylinder side of the compressor. .