JP2698117B2 - Air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial application field The present invention comprises an outdoor unit and a plurality of indoor units, and simultaneously cools or heats all of the plurality of rooms and simultaneously cools any room. The present invention relates to a multi-room air conditioner that heats another room.

(B) Conventional technology A multi-room air conditioner capable of simultaneously cooling or heating all of a plurality of rooms, and simultaneously cooling one of the plurality of rooms and heating the other room is disclosed in Japanese Patent Publication No. 5224710/1972. No. 52-24711 and Japanese Utility Model Publication No. 54-3020.

(C) Problems to be Solved by the Invention The devices presented in the above-mentioned JP-B-52-24710 and JP-B-52-24711 require four-way switching valves and outdoor heat exchangers by the number of indoor units. The piping circuit configuration becomes complicated and the manufacturing cost is high. Further, since two unit pipes have to be drawn out of the outdoor unit for each indoor unit, the number of unit-unit pipes is increased and piping work is troublesome. Had disadvantages. 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 apparatus presented in the above-mentioned Japanese Utility Model Publication No. 54-3020, a combination of a room capable of cooling and a room capable of heating is determined during a cooling / heating operation in which a certain room of a plurality of rooms is simultaneously cooled and another room is heated. The cooling and heating operation could not be freely selected and performed in each room, so that there was a drawback that the usability was poor.

An object of the present invention is to provide a multi-chamber air conditioner that solves the above-mentioned problems and facilitates on-site piping connection work.

(D) Means for Solving the Problems The present invention branches one end of an outdoor heat exchanger to a refrigerant discharge pipe and a refrigerant suction pipe of a compressor via a switching valve, and connects a pipe between units to a discharge pipe. Two high pressure gas pipes, a low pressure gas pipe connected to the suction pipe, and a liquid pipe connected to the other end of the outdoor heat exchanger, two pipe connection ports connected to the high pressure gas pipe And two pipe connection ports connected to the low-pressure gas pipe, two pipe connection ports connected to the liquid pipe, and a high-pressure gas pipe and a low-pressure gas pipe, which are branched and connected via a switching valve, and the indoor heat is connected. A pipe connection port connected to one end of the exchanger;
Each indoor unit is connected by piping to a branch unit which is connected to the liquid pipe and has a pipe connection port connected via a refrigerant pressure reducer and the other end of the indoor heat exchanger.

(E) Function When all the rooms are cooled at the same time, by setting the switching valve of the outdoor heat exchanger and the switching valve of each branch unit to the cooling state, the refrigerant discharged from the compressor is discharged from the discharge pipe through the outdoor heat exchanger. After flowing to the exchanger and condensed and liquefied here, it is distributed to the refrigerant decompressor of each indoor unit via the liquid pipe, and then, after evaporating and evaporating in each indoor heat exchanger, the low-pressure gas pipe and the refrigerant suction pipe Are sequentially sucked into the compressor. Thus, all the rooms are cooled by each indoor heat exchanger acting as an evaporator.

Also, when heating all the rooms at the same time, by setting the switching valve of the outdoor heat exchanger and the switching valve of the branching unit to the heating state, the refrigerant discharged from the compressor passes through the discharge pipe and the high-pressure gas pipe. After being sequentially decomposed into each indoor heat exchanger and condensed and liquefied here, they are merged in the liquid tubes through each refrigerant decompressor,
After that, after being evaporated and vaporized in the outdoor heat exchanger, it is 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.

In addition, when simultaneously cooling any two rooms, for example, heating one room, the switching valve of the outdoor heat exchanger is set to the heating state and the switching valve of the branch unit of the indoor unit to be cooled is set to the cooling state, And when the switching valve of the branch unit of the indoor unit to be heated is set to the heating state, part of the refrigerant discharged from the compressor flows to the outdoor heat exchanger and the remaining refrigerant is heated through the high-pressure gas pipe. It flows to the indoor heat exchanger and is condensed and liquefied by the indoor heat exchanger and the outdoor heat exchanger. The refrigerant condensed and liquefied by these heat exchangers is distributed to the refrigerant decompressor of each indoor unit via a liquid pipe, and then evaporated and vaporized by each indoor heat exchanger. Thereafter, the low-pressure gas pipe and the refrigerant suction pipe are formed. Are sequentially sucked into the compressor. 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.

(F) Embodiment An embodiment of the present invention will be described with reference to the drawings.
Is an outdoor unit having a compressor (2), an outdoor heat exchanger (3) and a gas-liquid separator (4), and (5a), (5b) and (5c) are indoor heat exchangers (6a) (6b) (6c) ), One end of an outdoor heat exchanger (3) is connected to a refrigerant discharge pipe (7) and a refrigerant suction pipe (8) of a compressor (2) by switching valves (9a) (9b).
A high-pressure gas branch-connected to the refrigerant discharge pipe (7) is connected between the outdoor unit (1) and the indoor unit (5a) (5b) (5c). A low pressure gas pipe (12) branched and connected to a pipe (11), a refrigerant suction pipe (8), and a liquid pipe (13) connected to the other end of the outdoor heat exchanger (3). , Each indoor heat exchanger (6a)
(6b) A gas branch pipe (14a) (15a) in which one end of (6c) is branched and connected to a high-pressure gas pipe (11) and a low-pressure gas pipe (12).
(14b) (15b), (14c) (15c) and the switching valves (16a) (17a), (16b) (17b), (16c) (1
7c) and the other end of each indoor heat exchanger (6a) (6b) (6c) is connected to the liquid pipe (13) via a refrigerant pressure reducer (18a) (18b) (18c) such as an electric expansion valve Liquid branch pipe (19a) (19b) (19
c) are provided in the branch units (20a), (20b), and (20c).

(21a) (21b) (21c) are capillary tubes (22a) (22b) (22
(23a) (23)
b) and (23c) are on-off valves smaller in diameter than the switching valves (17a), (17b) and (17c). These bypass pipes and on-off valves are connected in parallel with the switching valves (17a), (17b) and (17c), respectively. ,
The high-pressure gas pipe (11) and the liquid pipe (13) are connected to the capillary (24a) (24
b) Bypass pipe (25c) with throttle resistance by (24c)
a) Connect with (25b) and (25c) and use this capillary (24a)
Capillaries (26a) (26b) (26c) and on-off valves (27a) (27b) with smaller resistance than this capillary in parallel with (24b) (24c)
(27c) and these bypass pipes (21c
a) (21b) (21c), (25a) (25b) (25c) and on-off valves (23a) (23b) (23c) are (27a) (27b) (27c), and capillaries (26a) (26b) (26c) is also provided in the branch units (20a) (20b) (20c) as shown. still,
The bypass pipe (25a) (25b) (25c) is a high-pressure gas pipe (11)
And a low-pressure gas pipe (12). (28) is an auxiliary refrigerant decompressor such as an electric expansion valve interposed in the liquid pipe (13).

The air conditioner of the present invention is configured as described above,
The on-site refrigerant pipe connection work consists of three pipe connection ports (29) and branch units (20a) (20b) (20) of the outdoor unit (1).
c) A set of three pipe connection ports (30a) (31a), (30b)
(31b), (30c) and each branch unit (20a) (20b)
Two pipe connection ports (32a) (32b) (32c) of (20c) and two pipe connection ports (33a) (33b) (33c) of each indoor unit (5a) (5b) (5c) As shown in the figure, the pipes are connected and the three pipe connection ports (31
When c) is closed with a blind plug, the procedure is completed.

Next, the driving operation will be described. When cooling all the rooms at the same time, one switching valve (9a) of the outdoor heat exchanger (3) is opened, the other switching valve (9b) is closed, and the branch unit (20) is opened.
a) One of the switching valves (16a) (16b) (16)
c) is closed and the other switching valve (17a) (17b) (17c)
, The refrigerant discharged from the compressor (2) flows sequentially through the discharge pipe (7), the switching valve (9a), and the outdoor heat exchanger (3), where it is condensed and liquefied. ) And liquid branch pipes (19a) (19b) (19c) through each indoor unit (5a) (5
b) It is distributed to the refrigerant decompressors (18a), (18b), and (18c) of (5c), where the pressure is reduced. After that, each indoor heat exchanger (6a)
(6b) After evaporating in (6c), the switching valves (17a) (1
7b) (17c), on-off valves (23a) (23b) (23c), low-pressure gas pipe (12), suction pipe (8), and gas-liquid separator (4), which are sucked into compressor (2) in this order. . Thus, all the rooms are simultaneously cooled by the indoor heat exchangers (6a), (6b), and (6c) acting as evaporators.

During such simultaneous cooling operation, the on-off valves (27a) (27b) (27
c) is closed and the refrigerant discharged from the compressor (2) flows from the high-pressure gas pipe (11) to the bypass pipes (25a) (25b) (25).
Since the liquid is led to the liquid pipe (13) through each of c), the refrigerant does not accumulate in the high-pressure gas pipe (11).

Conversely, when heating all the rooms at the same time, one switching valve (9a) of the outdoor heat exchanger (3) is closed, the other switching valve (9b) is opened, and the branch units (20a) (20b) (20) are opened.
By opening one of the switching valves (16a), (16b), (16c) and closing the other switching valve (17a), (17b), (17c), the refrigerant discharged from the compressor (2) is discharged from the discharge pipe. (7),
Gas branch pipe (14a) (14b) through high-pressure gas pipe (11) sequentially
After being distributed to (14c), switching valves (16a) (16b) (16
c), flows to the indoor heat exchangers (6a), (6b), and (6c), where they are condensed and liquefied respectively, and then each refrigerant decompressor (18a) (18b)
After the pressure is reduced in (18c), the liquid is merged in the liquid pipe (13) through the liquid branch pipes (19a), (19b), and (19c). 9b), sucked into the compressor (2) through the suction pipe (8) and the gas-liquid separator (4) in that order. Thus, all the rooms are simultaneously heated by the indoor heat exchangers (6a) (6b) (6c) acting as condensers.

In order to simultaneously cool two rooms and heat one room at the same time, for example, one switching valve (9a) of the outdoor heat exchanger (3) is opened and the other switching valve (9b) is closed, and cooling is performed. Branch unit (20a) (20c) of indoor unit (5a) (5c)
The one switching valve (16b) in the branch unit (20b) of the indoor unit (5b) for heating and opening the other switching valve (17a) (17c) and opening the other switching valve (17a) (17c) When the other switching valve (17b) is opened and the other switching valve (17b) is closed, a part of the refrigerant discharged from the compressor (2) flows to the outdoor heat exchanger (3) through the discharge pipe (7) and the switching valve (9a) sequentially. At the same time, the remaining refrigerant flows to the switching valve (16b) of the branch unit (20b) and the indoor heat exchanger (6b) of the indoor unit (5b) for heating through the high-pressure gas pipe (11), and this indoor heat exchanger ( It is condensed and liquefied in 6b) and the outdoor heat exchanger (3). The refrigerant condensed and liquefied in the heat exchangers (6b) (3) passes through the liquid pipe (13) and passes through the indoor units (5a) (5c).
After being decompressed by the refrigerant decompressors (18a) and (18c), the refrigerant is evaporated and vaporized by the indoor heat exchangers (6a) and (6c), and then passed through the switching valves (17a) and (17c). They are merged by a pipe (12) and are sucked into a compressor (2) through a suction pipe (8) and a gas-liquid separator (4) in order. Thus, one room is heated by the indoor heat exchanger (6b) acting as a condenser, and two rooms are cooled by the other indoor heat exchangers (6a) (6c) acting as an evaporator.

Even during the simultaneous cooling and heating operation, the refrigerant discharged from the compressor (2) is guided from the high-pressure gas pipe (11) to the liquid pipe (13) via the bypass pipes (25a) and (25c). 11) No refrigerant will accumulate.

When the simultaneous cooling and heating operation is performed in winter, the indoor heat exchangers (6a) and (6c) of the indoor units (5a) and (5c) that are cooling because the low-pressure refrigerant pressure is affected by the outside air temperature
While the refrigerant pressure of the inner tends to decrease to 4 kg / cm ² or less, the pressure drop switching valve (17a) of diameter closes the (17c) smaller-off valve (23a) the indoor heat exchanger by opening the (23c) (6
a) It is prevented by increasing the pressure of the refrigerant outlet side of (6c), and the indoor heat exchangers (6a) and (6c) do not freeze.

Next, when cooling one room and heating two rooms, it is possible to operate the auxiliary refrigerant decompressor (28).

For example, when cooling with the indoor unit (5b) and heating with the indoor unit (5a) (5c), one of the switching valves (9a) of the outdoor heat exchanger (3) is closed and the other switching valve (9b) is opened. An indoor unit (5a) that closes one switching valve (16b) of the branch unit (20b) of the indoor unit (5b) to be cooled and opens the other switching valve (17b) and heats
One switching valve (16a) (16c) of the branch unit (20a) (20c) of (5c) is opened and the other switching valve (17a) (17
When c) is closed, the refrigerant discharged from the compressor (2) passes through the discharge pipe (7) and the high-pressure gas pipe (11) in order, and the switching valve (16a)
(16c) distributed to each indoor heat exchanger (6a) (6c)
Is condensed and liquefied. The liquefied refrigerant flows into the liquid pipe (13) via the refrigerant decompressors (18a) (18c) which are fully opened, respectively, and a part of the liquid refrigerant in the liquid pipe is converted into the refrigerant decompressor (18b)
And then the remaining liquid refrigerant is decompressed by the auxiliary refrigerant decompressor (28) and then evaporated and vaporized by the outdoor heat exchanger (3), and the suction pipe (8) , And sequentially sucked into the compressor (2) through the gas-liquid separator (4). Indoor heat exchangers acting as condensers (6a) (6c)
, Two rooms are heated, and one room is cooled by another indoor heat exchanger (6b) acting as an evaporator.

Even during the simultaneous cooling and heating operation, the refrigerant discharged from the compressor (2) is guided from the high-pressure gas pipe (11) to the liquid pipe (13) via the bypass pipe (25b), so that the high-pressure gas pipe (1
There is no accumulation of refrigerant in 1).

As described above, when the number of rooms to be cooled (cooling capacity) is larger than the number of rooms to be heated (heating capacity), the outdoor heat exchanger (3)
When the number of rooms to be heated (heating capacity) is smaller than the number of rooms to be cooled (coolant capacity), the outdoor heat exchanger (3) acts as an evaporator. Heating and cooling can be performed freely, and heat recovery is performed in each of the indoor heat exchangers that function as an evaporator and a condenser during the simultaneous cooling and heating operation, so that operation efficiency can be improved.

Also, during the above-mentioned cooling operation for all rooms, for example, the indoor unit (5
If only b) is switched to heating operation, the switching valve (16b) (17
b) is closed and the on-off valve (27b) is opened to raise the refrigerant pressure in the indoor heat exchanger (6b) in advance.
Opening b) prevents the generation of refrigerant noise due to the refrigerant pressure difference.

Similarly, during the heating operation in all rooms, for example, the indoor unit (5b)
When switching only to cooling operation, one switching valve (16b)
When the refrigerant pressure reducer (18b) is closed, the high-pressure refrigerant flows from the bypass pipe (21b) to the low-pressure gas pipe (12), and after the refrigerant pressure in the indoor heat exchanger (6b) drops, the switching valve (17b) is opened. Opening prevents the generation of refrigerant noise due to the refrigerant pressure difference.

The bypass pipes (21a), (21b), and (21c) serve to prevent refrigerant from accumulating in these indoor units when the indoor units (5a), (5b), (5c) stop cooling or heating operation. It also acts as a collector.

In the above embodiment, three indoor units (5a) (5b)
Although (5c) is used, even in the case of four or more indoor units having different capacities, it is only necessary to branch and connect the interunit piping (11) with the branch unit, and the piping connection work can be easily performed.

In the above embodiment, the switching valves (9a) (9b), (16a)
The two-way valves were used for (17a), (16b), (17b), (16c) and (17c), respectively. Instead, the switching valves (9a) and (9b) were replaced by three-way valves, and the switching valves (16a) and (17a) ) May be used as a three-way valve so that a total of four three-way valves may be used.

(G) Effect of the Invention In the present invention, the unit-unit piping connecting the outdoor unit and the plurality of indoor units is constituted by three refrigerant pipes of a high-pressure gas pipe, a low-pressure gas pipe, and a liquid pipe. Any number of indoor units can be combined simply by branching and connecting them to the piping between the units. Simultaneous cooling and heating operations of multiple indoor units as well as simultaneous cooling and heating operations can be freely selected and performed by any indoor unit. 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 simultaneous cooling and heating operation, efficient operation by heat recovery can be performed.

Moreover, two pipe connection ports connected to the high-pressure gas pipe, two pipe connection ports connected to the low-pressure gas pipe, two pipe connection ports connected to the liquid pipe, a high-pressure gas pipe and a low-pressure gas pipe And a pipe connection port connected to one end of the indoor heat exchanger and connected to a liquid pipe and connected to the other end of the indoor heat exchanger via a refrigerant pressure reducer. Since each of the indoor units is connected to the branch unit having a pipe connection port, the pipe connection work on site can be easily performed, and only two pipes are required to be taken out from each indoor unit as described above. In addition, the number of pipes can be minimized.

[Brief description of the drawings]

The drawing is a refrigerant circuit diagram of an air conditioner showing an embodiment of the present invention. (1) ... outdoor unit, (2) ... compressor, (3) ...
... outdoor heat exchanger, (5a) (5b) (5c) ... indoor unit, (6a) (6b) (6c) ... indoor heat exchanger, (7) ...
Refrigerant discharge pipe, (8) ... refrigerant suction pipe, (9a) (9b) ...
Switching valve, (10) ... Unit-to-unit piping, (11) ... High-pressure gas pipe, (12) ... Low-pressure gas pipe, (13) ... Liquid pipe, (14)
a) (15a), (14b) (15b), (14c) (15c) ... gas branch pipe, (16a) (17a), (16b) (17b), (16c) (1
7c) Switching valve (18a) (18b) (18c) Refrigerant pressure reducer (19a) (19b) (19c) Liquid branch pipe (20a) (20)
b) (20c) ... Branch unit.

Claims (1)

(57) [Claims] 1. An air conditioner in which an outdoor unit having a compressor and an outdoor heat exchanger and a plurality of indoor units having an indoor heat exchanger are connected by inter-unit piping, and one end of the outdoor heat exchanger is provided. Is connected to a refrigerant discharge pipe and a refrigerant suction pipe of the compressor via a switching valve, while a unit-to-unit pipe is connected to the discharge pipe and a high-pressure gas pipe is connected to the suction pipe. And a liquid pipe connected to the other end of the outdoor heat exchanger, two pipe connection ports connected to the high-pressure gas pipe, and two pipe connection ports connected to the low-pressure gas pipe And two pipe connection ports connected to the liquid pipe, and a pipe connection port branched and connected to the high-pressure gas pipe and the low-pressure gas pipe via a switching valve and connected to one end of the indoor heat exchanger. And the indoor heat exchange connected to the liquid pipe. Air conditioner, characterized in that at the branching unit and a pipe connecting port which is connected through the other end and the refrigerant pressure reducer was the indoor units connected by piping in.