JPH0926219A - Cooling/heating apparatus for many rooms - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to recover heat and to control the cooling or heating operation in a manner of arbitrary selection in each room by using a high-pressure gas pipe, low-pressure gas pipe, and liquid pipe that together constitute a unit-to-unit piping connecting one set of outdoor apparatus containing a plurality of outdoor heat exchangers to a plurality of individual indoor apparatuses. SOLUTION: Outdoor heat exchangers 3a, 3b are each connected to a refrigerant- discharge pipe 7 and a refrigerant-suction pipe 8 of a compressor 2 by branches having directional control valves 9a, 10a, 9b, 10b. A high-pressure gas pipe 12 branching from and connected to the refrigerant-discharge pipe 7, a low-pressure gas pipe 13 branching from and connected to the refrigerant-suction pipe 8, and a liquid pipe 14 connected to the outdoor heat exchangers 3a, 3b together constitute a unit-to-unit piping 11 which connects a set of outdoor apparatus 1 to individual indoor apparatuses 5a-5c. Each of indoor heat exchangers 6a-6c is connected to the high-pressure gas pipe 12 and the low-pressure gas pipe 13 by branches having directional control valves 15a, 16a, 15b, 16b, 15c, 16c respectively and to the liquid pipe 14 through refrigerant- pressure reducers 17a, 17b, 17c, such as motor-operated expansion valves, respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises an outdoor unit and a plurality of indoor units, and cools or heats all of the plurality of rooms at the same time, and cools one room at the same time and heats another room. Regarding the device.

[0002]

2. Description of the Related Art A multi-room type air conditioner capable of cooling or heating all of a plurality of rooms at the same time, and simultaneously cooling one room of a plurality of rooms and heating another room is disclosed in Japanese Examined Patent Publication Nos. 52-24710 and 52-2471. Publication, Japanese Examined Patent Publication No. 52-27459
Japanese Patent Publication No. 54-3020.

[0003]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
The devices disclosed in Japanese Patent No. 4710 and Japanese Patent Publication No. 52-24711 require four-way switching valves and outdoor heat exchangers for the number of indoor units, which complicates the piping circuit configuration and increases the manufacturing cost. 2 for each indoor unit
Since the inter-unit piping of the book has to be pulled out from the outdoor unit, there is a drawback that the number of inter-unit piping is large and the piping work is troublesome. Moreover, at the same time, during the cooling / heating operation for cooling one room and heating the other room, the outdoor heat exchangers corresponding to the respective indoor units act as condensers and evaporators, respectively, and dissipate heat to the outside. there were.

Further, in the devices disclosed in Japanese Patent Publication No. 52-27459 and Japanese Utility Model Publication No. 54-3020, a room which can be cooled during a heating / cooling operation in which a plurality of rooms are cooled at the same time and the other rooms are heated. The combination with the room that can be heated has been decided, and it is not possible to freely select and perform the heating / cooling operation in each room, and there is a drawback that the usability is poor.

An object of the present invention is to provide a multi-chamber type cooling and heating apparatus that solves the above problems.

[0006]

According to the present invention, an outdoor unit containing a compressor and an outdoor heat exchanger, a plurality of indoor units containing an indoor heat exchanger, and a unit to which these two units are connected. And an inter-unit pipe branchingly connected to the refrigerant discharge pipe and the refrigerant suction pipe of the compressor via a first switching valve. A high-pressure gas pipe, a low-pressure gas pipe branched from the refrigerant suction pipe, and a liquid pipe connected to a plurality of outdoor heat exchangers, and each indoor heat exchanger is connected to the high-pressure gas pipe and the low-pressure gas pipe. The pipe and the low-pressure gas pipe are branched and connected through a second switching valve, and the liquid pipe is connected through a refrigerant decompressor so that the indoor unit can simultaneously perform cooling operation and heating operation. In a room type air conditioner, the outdoor heat exchange Vessel is provided parallel a plurality, it is characterized in changing the number of the outdoor heat exchanger to act in accordance with the load of the device.

When cooling all the rooms at the same time, the refrigerant discharged from the compressor is discharged from the discharge pipe by setting the switching valve of each outdoor heat exchanger and the switching valve of each indoor heat exchanger to the cooling state. After flowing parallel to each outdoor heat exchanger and condensing and liquefying here, it is distributed to the refrigerant decompressor of each indoor unit through a liquid pipe, and after that, after evaporating and vaporizing in each indoor heat exchanger, with a low pressure gas pipe It is sucked into the compressor through the refrigerant suction pipe in order. Thus, all the rooms are cooled by each indoor heat exchanger acting as an evaporator. When the cooling load is small during such a cooling operation, some of the plurality of outdoor heat exchangers act as condensers.

When heating all the rooms at the same time, the refrigerant discharged from the compressor is discharged by setting the switching valve of each outdoor heat exchanger and the switching valve of each indoor heat exchanger to the heating state. Pipes and high-pressure gas pipes are sequentially distributed to the indoor heat exchangers, where they are condensed and liquefied, respectively, and then merged with the liquid pipes via the refrigerant depressurizers, and then are co-flowed to the outdoor heat exchangers. After being evaporated and vaporized respectively, they are sucked into the compressor through the refrigerant suction pipe. In this way, all the rooms are heated by each indoor heat exchanger acting as a condenser. When the heating load is small during such a heating operation, some of the plurality of outdoor heat exchangers act as an evaporator.

Further, when, for example, cooling two arbitrary chambers and heating one chamber at the same time, the switching valve of one outdoor heat exchanger is set to the cooling state and the switching valve of the other outdoor heat exchanger is closed. And when the switching valve of the indoor heat exchanger of the indoor unit to be cooled is set to the cooling state and the switching valve of the indoor heat exchanger of the indoor unit to be heated is set to the heating state, some of the refrigerant discharged from the compressor While flowing only to one of the outdoor heat exchangers, the remaining refrigerant flows to the indoor heat exchanger of the indoor unit for heating via the high pressure gas pipe, and is condensed and liquefied by the indoor heat exchanger and the outdoor heat exchanger. And the refrigerant condensed and liquefied by these heat exchangers is distributed to the refrigerant decompressor of each indoor unit via the liquid pipe, and then evaporated and vaporized by each indoor heat exchanger,
Thereafter, the refrigerant is sucked into the compressor through the low-pressure gas pipe and the refrigerant suction pipe sequentially. Thus, one room is heated by the indoor heat exchanger acting as a condenser, and two rooms are cooled by another indoor heat exchanger acting as an evaporator. When the difference between the cooling load and the heating load is small during such simultaneous cooling and heating operation, only a part of the plurality of outdoor heat exchangers acts as a condenser or an evaporator.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described with reference to FIG. 1. Reference numeral 1 denotes a compressor 2 and outdoor heat exchangers 3a and 3a.
b, an outdoor unit having a gas-liquid separator 4 and 5a, 5
b and 5c are indoor units having indoor heat exchangers 6a, 6b and 6c, and the outdoor heat exchangers 3a and 3b are switched to the refrigerant discharge pipe 7 and the refrigerant suction pipe 8 of the compressor 2 by the switching valves 9a, 10a and 9c.
outdoor unit 1 while branching and connecting via b and 10b
A high-pressure gas pipe 12 branch-connected to the refrigerant discharge pipe 7 and a low-pressure gas pipe 13 branch-connected to the refrigerant suction pipe 8 are connected between the unit and the indoor units 5a, 5b, 5c.
And a liquid pipe 14 connected to the outdoor heat exchangers 3a and 3b, and the indoor heat exchangers 6a, 6b and 6c are connected to the high pressure gas pipe 12 and the low pressure gas pipe 13, respectively, by a switching valve 15a, 16
The refrigerant pressure reducer 1 such as an electric expansion valve is connected to the liquid pipe 14 through a branch connection via a, 15b, 16b, 15c, 16c.
It is connected via 7a, 17b and 17e.

Reference numerals 18a and 18b denote auxiliary refrigerant hydraulic devices such as an electric expansion valve interposed in the liquid pipe 14.

Next, the driving operation will be described. When cooling all the rooms at the same time, one of the switching valves 9a, 9b of each of the outdoor heat exchangers 3a, 3b is opened and the other switching valve 10a, 1 is opened.
0b, and by closing one switching valve 15a, 15b, 15e of the indoor heat exchangers 6a, 6b, 6c and opening the other switching valve 16a, 16b, 16c, the refrigerant discharged from the compressor 2 is Discharge pipe 7, switching valves 9a, 9b
After sequentially flowing with the outdoor heat exchangers 3a and 3b and condensing and liquefying there, the indoor units 5a, 5b and 5c are passed through the liquid pipe 1d.
Are distributed to the refrigerant decompressors 17a, 17b, 17c and are decompressed here. After that, each indoor heat exchanger 6a, 6b, 6
After evaporating in c, the switching valves 16a, 16b, 16
c, the low-pressure gas pipe 13, the suction pipe 8, and the gas-liquid separator 4 in that order, and then sucked into the compressor 2. In this way, all the indoor heat exchangers 6a, 6b, 6c acting as evaporators cool all the rooms at the same time.

During such cooling operation, for example, the indoor unit 5
When b and / or 5c are thermo-off and the cooling operation is stopped and the cooling load is reduced, one of, for example, the outdoor heat exchanger 3b
When the switching valves 9b and 10b are closed, the outdoor heat exchanger 3b stops operating as a condenser and is operated with a condenser capacity commensurate with the cooling load.

On the contrary, when heating all the rooms at the same time, the switching valves 9a, 9b of the outdoor heat exchangers 3a, 3b are closed and the other switching valves 10a, 10b are opened, and the indoor heat exchangers 6a, 6b, 6c one of the switching valves 15a, 15b,
15c is opened and the other switching valves 16a, 16b, 16
By closing c, the refrigerant discharged from the compressor 2 sequentially passes through the discharge pipe 7 and the high-pressure gas pipe 12, and the changeover valves 15a, 1
5b, 15c, and the indoor heat exchangers 6a, 6b, 6c, where they are condensed and liquefied respectively, and then each refrigerant pressure reducer 17
a, 17b, 17c are decompressed and merged in the liquid pipe 14,
After that, after evaporating and vaporizing in the outdoor heat exchangers 3a and 3b, they are sucked into the compressor 2 through the switching valves 10a and 10b, the suction pipe 8 and the gas-liquid separator 4 in this order. In this way, all the indoor heat exchangers 6a, 6b, 6c acting as condensers simultaneously heat all the rooms.

During such heating operation, for example, the indoor unit 5
When b and / or 5c are thermo-off and the heating operation is stopped and the heating load is reduced, one of, for example, the outdoor heat exchanger 3b
The switching valves 9b and 10b are closed, the outdoor heat exchanger 3b stops operating as an evaporator, and the outdoor heat exchanger 3b is operated with the evaporator capacity corresponding to the heating load. Further, when, for example, cooling two arbitrary chambers and heating one chamber at the same time, one switching valve 9a of the outdoor heat exchanger 3a is opened and the other switching valve 10a and the outdoor heat exchanger 3b are both switching valves 9b. , 10b, and one of the switching valves 15a, 1 of the indoor units 5a, 5c for cooling.
5c is closed, the other switching valves 16a and 16c are opened, and one switching valve 15 of the indoor unit 5b for heating is also provided.
When b is opened and the other switching valve 16b is closed, a part of the refrigerant discharged from the compressor 2 sequentially flows through the discharge pipe 7 and the switching valve 9a to only one outdoor heat exchanger 3a, and the remaining refrigerant remains. It flows to the switching valve 15b of the indoor unit 5b for heating via the high-pressure gas pipe 12 and the indoor heat exchanger 6b, and is condensed and liquefied by the indoor heat exchanger 6b and the outdoor heat exchanger 3a. The refrigerant condensed and liquefied in the heat exchangers 6b and 3a is decompressed in the refrigerant decompressors 17a and 17c of the indoor units 5a and 5c through the liquid pipe 14, and then evaporated in the respective indoor heat exchangers 6a and 6c. After being vaporized, each switching valve 16
After passing through a and 16c, they are merged in the low-pressure gas pipe 13, and are sequentially sucked into the compressor 2 through the suction pipe 8 and the gas-liquid separator 4. In this way, one room is heated by the indoor heat exchanger 6b acting as a condenser, and the other indoor heat exchanger 6 acting as an evaporator.
The two chambers are cooled by a and 6c.

During such simultaneous heating and cooling operation, the indoor unit 5
Although the refrigerant pressure reducer 17b of b is fully opened to prevent the refrigerant pressure loss, the pressure is adjusted by the auxiliary pressure reducer 18a so that the pressure of the liquid refrigerant in the liquid pipe 14 does not become unbalanced.

Further, if such simultaneous cooling and heating operation is performed in the summer when the outside air temperature is high, the outdoor heat exchanger 3a cannot sufficiently extract the heat source from the outside air, and the cooling capacity is deteriorated. In such an operating state, the switching valve 9b is opened and a part of the refrigerant discharged from the discharge pipe 7 is transferred to the other outdoor heat exchanger 3b.
After condensing and liquefying after flowing into the liquid refrigerant, it comes to join the liquid pipe 14 through the auxiliary refrigerant decompressor 18b, and the outdoor heat exchanger 3b acting as a condenser further draws a heat source from the outside air to reduce the cooling capacity. To prevent. In addition, during this summer operation, for example, when the indoor unit 5c thermostats off and the cooling operation is stopped, and the cooling load is reduced, the amount of heat source pumped from the outside air may be small. Therefore, for example, one of the switching valves 9a, 1
0a is closed and only the other outdoor heat exchanger 3b acts as a condenser.

Next, when cooling one chamber and heating two chambers, it is possible to operate the auxiliary refrigerant decompressor 18a.

For example, when the indoor unit 5b is used for cooling and the indoor units 5a, 5c are used for heating, one switching valve 10a of the outdoor heat exchanger 3a is opened and the other switching valve 9a, 9 is opened.
b, 10b are closed, and one switching valve 15b of the indoor unit 5b for cooling is closed and the other switching valve 16b is opened, and one switching valve 15a, 15c of the indoor units 5a, 5c for heating is opened and the other switching valve 15b is opened. Switching valve 16a,
When 16c is closed, the refrigerant discharged from the compressor 2 sequentially passes through the discharge pipe 7 and the high pressure gas pipe 12, and then the switching valves 15a and 15c.
And is condensed and liquefied in the respective indoor heat exchangers 6a and 6c. The liquefied refrigerant flows into the liquid pipe 14 through the fully opened refrigerant decompressors 17a and 17c, respectively, and a part of the liquid refrigerant in the liquid pipe is decompressed by the refrigerant decompressor 17b, and then the indoor heat exchanger 6b. In addition, the remaining liquid refrigerant is decompressed by the auxiliary refrigerant decompressor 18a, then evaporated and vaporized by the outdoor heat exchanger 3a, and then sucked into the compressor 2 through the suction pipe 8 and the gas-liquid separator 4. In this way, the two chambers are heated by the indoor heat exchangers 6a and 6c which act as condensers, and the one chamber is cooled by the other indoor heat exchanger 6b which acts as an evaporator.

If such a simultaneous heating and cooling operation is performed in the winter when the outside air temperature is low, the outdoor heat exchanger 3a cannot sufficiently extract the heat source from the outside air and the heating capacity is deteriorated. In such an operating state, the switching valve 10b is opened, the auxiliary refrigerant decompressor 18b operates, and the other outdoor heat exchanger 3b also functions as an evaporator, so that the reduction of the heating capacity is prevented. When the indoor unit 5c thermostats off and the heating operation is stopped and the heating load is reduced during this winter operation, the heat source pumping amount from the outside air may be small. For example, one of the switching valves 9a and 10b is closed. On the other hand, only the other outdoor heat exchanger 3b acts as an evaporator.

In this way, each indoor unit 5a, 5b,
5c is each switching valve 15a, 16a, 15b, 16b,
15c, 16c and each switching valve 9 for the outdoor heat exchangers 3a, 3b
It is possible to arbitrarily perform heating / cooling operation by opening / closing a, 10a, 9b, 10b, and further, heat recovery by the respective indoor heat exchangers 6a, 6b, 6c which act as an evaporator and a condenser during simultaneous cooling / heating operation. The operation efficiency can be improved.

When the outdoor heat exchangers 3a and 3b functioning as evaporators during the heating operation for all the rooms are frosted, one switching valve 9a is opened and the other switching valve 10a is closed to exchange one outdoor heat. The outdoor heat exchanger 3a is defrosted by guiding a part of the high-temperature discharge refrigerant from the discharge pipe 7 to the container 3a, and then the one switching valve 9a is closed and the other switching valve 10a is opened. By causing one of the outdoor heat exchangers 3a to act again as an evaporator, the switching valve 9b is opened and the switching valve 10b is closed to guide one of the hot discharge refrigerants from the discharge pipe 7 to the other outdoor heat exchanger 3b. The heating operation for all rooms is continuously performed while defrosting the outdoor heat exchangers 3a and 3b in such a manner that the outdoor heat exchanger 3b is defrosted.

Further, during the simultaneous cooling and heating operation in which one of the outdoor heat exchangers 3a and 3b acts as an evaporator and the other one is deactivated, one outdoor heat exchanger 3a acting as an evaporator is worn. In the case of frost, one of the switching valves 9a and 10a is switched to defrost the outdoor heat exchanger 3a, and at the same time, the other switching valve 9b and 10b is switched to operate the outdoor heat exchanger 3b as an evaporator. The operation continues.

FIG. 2 shows another embodiment of the present invention, which differs from the previous embodiment in that the outdoor units 1a, 1
Two b are provided, and one outdoor unit 1a has a variable capacity compressor 2a having a variable compression capacity, an outdoor heat exchanger 3a, a gas-liquid separator 4a, switching valves 9a and 10a, and an auxiliary refrigerant decompressor 18.
While having a built-in a, the other outdoor unit 1b has a constant capacity compressor 2b whose compression capacity does not change and an outdoor heat exchanger 3b.
The gas-liquid separator 4b, the switching valves 9b and 10b, and the auxiliary refrigerant decompressor 18b are built in, and the refrigerant discharge pipes 7a and 7b are connected to the high pressure gas pipe 12 and the refrigerant suction pipes 8a and 8b are connected to the low pressure gas pipe 13. This is the point where the switching valves 9a, 10a, 9b, 10b, 15a, 16a, 15 are connected, as in the above embodiment.
By opening / closing b, 16b, 15c, 16c, all room cooling operation, all room heating operation and simultaneous cooling / heating operation can be performed.

In the above embodiment, three indoor units 5 are used.
Although a, 5b, and 5c are used, even in the case of four or more indoor units having different capacities, it is sufficient to simply branch and connect to the inter-unit pipe 11 and the outdoor heat exchanger according to the number of indoor units. Alternatively, the number of outdoor heat exchangers or the number of outdoor units can be easily increased by branching the outdoor units.

Further, in both of the above embodiments, the switching valves 9a, 10
a, 9b, 10b, 15a, 16a, 15b, 16b,
Although two-way valves are used for 15c and 16c, respectively, five switching valves 9a and 10a may be used instead of three-way valves, and switching valves 9b and 10b may be used for three-way valves.
Further, in the above embodiment, a plurality of outdoor heat exchangers 3a and 3b are used.
However, the outdoor heat exchangers 3a and 3b may be integrally formed.

[0027]

According to the present invention, one outdoor unit containing a plurality of outdoor heat exchangers and inter-unit piping for connecting a plurality of indoor units, a high pressure gas pipe, a low pressure gas pipe, and a liquid pipe. Since it is composed of three refrigerant pipes, it is possible to combine as many indoor units as possible by simply branching and connecting the indoor units to the inter-unit piping, as well as simultaneous cooling and heating operations for multiple indoor units, as well as simultaneous heating and cooling operations. The operation can be freely selected and performed in any indoor unit, and the operating capacities of a plurality of outdoor heat exchangers are changed according to the cooling / heating load during the simultaneous cooling operation, simultaneous heating operation, and simultaneous cooling / heating operation. As a result, efficient cooling / heating operation can be performed under the optimum refrigerant pressure.

In addition, since the indoor heat exchanger acting as a condenser and the indoor heat exchanger acting as an evaporator are connected in series during the simultaneous heating / cooling operation, efficient operation can be performed by heat recovery. .

Further, if a plurality of outdoor heat exchangers are built in one outdoor unit, the installation area can be kept small, and if a plurality of outdoor units are provided, the outdoor units can be installed according to the number of indoor units. You can easily increase or decrease the number of units.

[Brief description of drawings]

FIG. 1 is a refrigerant circuit diagram of a multi-room air conditioner according to an embodiment of the present invention.

FIG. 2 is a refrigerant circuit diagram of a multi-room air conditioner according to an embodiment of the present invention.

[Explanation of symbols]

1, 1a, 1b Outdoor unit 2, 2a, 2b Compressor 3a, 3b, Outdoor heat exchanger 5a, 5b, 5c Indoor unit 6a, 6b, 6c Indoor heat exchanger 7, 7a, 7b Refrigerant discharge pipe 8, 8a, 8b Refrigerant suction pipe 9a, 10a, 9b, 10b Switching valve 11 Inter-unit piping 12 High pressure gas pipe 13 Low pressure gas pipe 14 Liquid pipe 15a, 16a, 15b, 16b, 15e, 16e Switching valve 17a, 17b, 17c Refrigerant pressure reducer

Claims (2)

[Claims] 1. An outdoor unit containing a compressor and an outdoor heat exchanger, a plurality of indoor units containing an indoor heat exchanger, and inter-unit piping connecting these units, The outdoor heat exchanger is branched and connected to the refrigerant discharge pipe and the refrigerant suction pipe of the compressor via the first switching valve, while the inter-unit pipe is a high pressure gas pipe branched and connected to the refrigerant discharge pipe, and the refrigerant. It consists of a low pressure gas pipe branched from the suction pipe and a liquid pipe connected to a plurality of outdoor heat exchangers, and each indoor heat exchanger is divided into the high pressure gas pipe, the low pressure gas pipe and the low pressure gas pipe. A multi-chamber cooling / heating apparatus, which is branched and connected via a second switching valve and is connected to the liquid pipe via a refrigerant decompressor so that the indoor unit can perform a cooling operation and a heating operation at the same time. Multiple heat exchangers should be installed in parallel. A multi-chamber type air conditioning apparatus characterized by changing the number of the outdoor heat exchanger to act in accordance with the load of the device. 2. An outdoor unit having a compressor and an outdoor heat exchanger built therein, a plurality of indoor units having an indoor heat exchanger built therein, and an inter-unit pipe connecting these units, The outdoor heat exchanger is branched and connected to the refrigerant discharge pipe and the refrigerant suction pipe of the compressor via the first switching valve, while the inter-unit pipe is a high pressure gas pipe branched and connected to the refrigerant discharge pipe, and the refrigerant. It consists of a low pressure gas pipe branched from the suction pipe and a liquid pipe connected to a plurality of outdoor heat exchangers, and each indoor heat exchanger is divided into the high pressure gas pipe, the low pressure gas pipe and the low pressure gas pipe. A multi-chamber cooling / heating apparatus, which is branched and connected via a second switching valve and is connected to the liquid pipe via a refrigerant decompressor so that the indoor unit can perform a cooling operation and a heating operation at the same time. Multiple heat exchangers should be installed in parallel. A multi-chamber type air conditioning apparatus characterized by changing the number of the outdoor heat exchanger to act in accordance with the difference between the cooling load and the heating load of the device.