JP2777459B2 - Air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial application field The present invention is composed of one heat source side unit and a plurality of utilization side units, and simultaneously cools or heats all of a plurality of rooms and simultaneously arbitrarily arbitrarily. The present invention relates to a multi-room air conditioner for cooling a certain room and heating another room.

(B) Conventional technology A heat source side unit having a compressor and a heat source side heat exchanger, and a plurality of use side units having a use side heat exchanger and a refrigerant decompressor are connected to a high pressure gas pipe and a low pressure gas pipe. A switching valve for switching between the heat source side heat exchanger and the use side heat exchanger individually as a condenser or an evaporator is provided while connecting with a unit pipe comprising a liquid pipe, and all of the plurality of chambers are simultaneously operated. A multi-room air conditioner for cooling or heating and simultaneously cooling an arbitrary room and heating another room is disclosed in JP-A-61-11.
No. 0833.

(C) Problems to be Solved by the Invention In the device presented in the above-mentioned publication, for example, at the time of simultaneous cooling / heating operation in which one use side unit heats one room and two use side units cools two rooms, It is necessary to increase the high-pressure refrigerant pressure of the compressor in order to increase the heating capacity of one use-side unit. However, from the viewpoint of the use-side unit performing the cooling operation, maintaining the high-pressure pressure high is the operating result. This has led to a decrease in the coefficient, and there has been a problem in that the operating efficiency has deteriorated.

In view of the above, it is an object of the present invention to provide an air conditioner that improves heating capacity and operation efficiency during simultaneous cooling and heating operations.

(D) Means for Solving the Problems The present invention provides an air conditioner in which a compressor, a heat source side heat exchanger, and a plurality of use side heat exchangers are connected by refrigerant pipes, wherein a plurality of compressors are provided. A high-pressure gas refrigerant pipe to which the discharge pipe of each compressor is connected and a low-pressure gas refrigerant pipe to which the suction pipe is connected are connected to one end of each of the heat source side heat exchanger and the use side heat exchanger via a switching valve. At the same time, the other end of the heat source side heat exchanger and the other end of the use side heat exchanger are connected by a liquid refrigerant pipe via a refrigerant decompressor, and the high pressure gas refrigerant pipe has a refrigerant at an intermediate position between a plurality of compressors. A control valve is provided.

Further, the present invention provides an air conditioner in which a compressor, a heat source side heat exchanger, and a plurality of use side heat exchangers are connected by refrigerant pipes. The high-pressure gas refrigerant pipe to which the pipe is connected and the low-pressure gas refrigerant pipe to which the suction pipe of the compressor is connected are connected via a switching valve to one end of each of the heat source side heat exchanger and the use side heat exchanger, The other end of the heat source side heat exchanger and the other end of the utilization side heat exchanger are connected by a liquid refrigerant pipe via a refrigerant decompressor, and the refrigerant main control is located at an intermediate position between a plurality of discharge pipes in the high pressure gas refrigerant pipe. A valve is provided, and a refrigerant sub-control valve is provided on at least one of the discharge pipes.

(E) Function When cooling all the rooms at the same time, the heat source side switching valve and the utilization side switching valve are set to the cooling state and the refrigerant control valve is opened, so that a plurality of compressors or a plurality of discharge pipes are opened. The discharged refrigerant flows through the heat source side switching valve to the heat source side heat exchanger, where it is condensed and liquefied.Then, the refrigerant is distributed to the refrigerant decompressor of each use side unit through the liquid pipe, and then each use side heat After being evaporated and vaporized by the exchanger, it is sucked into the compressor through the use side switching valve, the low pressure gas pipe, and the refrigerant suction pipe in order. In this way, all the rooms are cooled by each use-side heat exchanger acting as an evaporator.

Also, when heating all the rooms at the same time, by setting the heat source side switching valve and the utilization side switching valve to the heating state and opening the refrigerant control valve, the refrigerant discharged from the compressor passes through the high pressure gas pipe to each After being distributed to the use side heat exchanger and condensed and liquefied respectively here, they are joined by the liquid tubes through the respective refrigerant decompressors, and then flow to the heat source side heat exchangers to evaporate and vaporize, respectively. After that, it is sucked into the compressor. In this way, all the rooms are heated by each use side heat exchanger acting as a condenser.

In addition, when simultaneously cooling any two rooms and heating one room at the same time, for example, the heat source side switching valve is set to the cooling state, the refrigerant control valve is closed, and the switching valve of the user side unit for cooling is set to the cooling state. When the switching valve of the use side unit for heating and heating is set to the heating state, the refrigerant discharged from one compressor flows to the heat source side heat exchanger and the refrigerant discharged from the other compressor passes through the high pressure gas pipe. The heat flows to the use side exchanger of the use side unit to be heated, and is condensed and liquefied by the heat exchanger and the heat source side heat exchanger. The refrigerant condensed and liquefied by these heat exchangers is distributed to the refrigerant decompressor of each usage-side unit via a liquid pipe, and then evaporated and vaporized in each usage-side heat exchanger. It is sucked into a compression tube through the suction pipe. In this way, one room is heated by the use side heat exchanger acting as a condenser, and two rooms are cooled by another use side heat exchanger acting as an evaporator.

(F) Embodiment The first embodiment of the present invention will be described with reference to FIG. 1. (1) is a combination of two variable capacity compressors (2a) and (2b) whose operating frequency is changed by an inverter device. Liquid separator (3
a) a mechanical unit having (3b); (4) two heat source side heat exchangers (5a) (5b) and heat source side switching valves (6a) (7
a), (6b), (7b) and refrigerant decompressors (8
a) (8b) and (9a) (9b) (9
c) is a use side unit having a use side heat exchanger (10a) (10b) (10c) and a refrigerant decompressor (11a) (11b) (11c) such as an electric expansion valve, and (12) is a use side switch Valve (13a) (13b)
(13c), (14a) (14b) A branch unit having (14c), (15) an inter-unit pipe comprising a high-pressure gas refrigerant pipe (16), a low-pressure gas refrigerant pipe (17), and a liquid refrigerant pipe (18) The high-pressure gas refrigerant pipe (16) to which the discharge pipes (19a) (19b) of each compressor (2a) (2b) are connected, and the suction pipes (20a) (20b)
Is connected to the low pressure gas refrigerant pipe (17), the heat source side heat exchanger (5a) (5b) and the use side heat exchanger (10a) (10b) (10c)
The heat source side switching valve (6a) (7a), (6b) (7
b) and user-side switching valves (13a) (14a), (13b) (14
b), (13c), (14c) and the other end of the heat source side heat exchanger (5a) (5b) and the use side heat exchanger (10a)
(10b) The other end of (10c) and the refrigerant decompressor (8a) (8b),
The liquid refrigerant pipe (18) is connected via (17a), (17b) and (17c), and the high-pressure gas refrigerant pipe (16) in the mechanical unit (1) is located at an intermediate position between the two compressors (2a) and (2b). Is provided with an electrically operated refrigerant control valve (21).

(22) is a controller for controlling the opening degree of the refrigerant control valve (21), and is a use side unit (9a) (9b) (9c)
And outputs a control signal for changing the valve opening by the cooling / heating operation, and also outputs a variable capability signal for changing the operating frequency of both compressors (2a) and (2b).

Next, the driving operation will be described. When cooling all the rooms at the same time, one of the heat source side switching valves (6a) and (6b) is opened, and the other heat source side switching valves (7a) and (7b) are closed. ) (13c) is closed and the other usage-side switching valves (14a) (14b) (14c) are opened, and the control valve (2
By closing 1), the refrigerant discharged from the compressors (2a) (2b) discharges the discharge pipes (19a) (19b), the high-pressure gas refrigerant pipe (16), the heat source side switching valves (6a) (6b), and the heat source After flowing sequentially through the side heat exchangers (5a) and (5b) and condensed and liquefied here, they pass through the refrigerant decompressors (8a) and (8b) in the fully open state, and through the liquid refrigerant pipe (18), to each use-side unit (9a) ( 9b) (9c) refrigerant pressure reducer (11
a) Partitioned into (11b) and (11c), where the pressure is reduced. Then, after evaporating and evaporating in each use side heat exchanger (10a) (10b) (10c), the switching valves (14a) (14b) (14c), the low-pressure gas refrigerant pipe (17), and the suction pipe (20a ) (20b) and gas-liquid separators (3a), (3b), and then sucked into the compressors (2a) (2b). As described above, all the rooms are simultaneously cooled by the use-side heat exchangers (10a) (10b (10c)) which function as evaporators.

Conversely, when heating all the rooms simultaneously, one of the heat source side switching valves (6a) and (6b) is closed and the other heat source side switching valve (7
a) Open (7b) and use one of the usage side switching valves (13a) (13b)
(13c) is opened and the other usage-side switching valve (14a) (14
b) By closing the (14c) and the control valve (21), the refrigerant discharged from the compressors (2a) (2b) is discharged from the discharge pipes (19a) (19).
b), switching valve (13a) through high-pressure gas refrigerant pipe (16) sequentially
(13b) (13c), use side heat exchanger (10a) (10b) (10
c), where they are condensed and liquefied respectively, and then passed through the refrigerant decompressors (11a), (11b), and (11c) in the fully open state to form a liquid pipe (1).
8), and then decompressed by the refrigerant decompressors (8a) and (8b) and evaporated and vaporized by the heat source side heat exchangers (5a) and (5b). Then, the heat source side switching valves (7a) and (7b) , Low-pressure gas refrigerant pipe (1
7), suction pipe (20a) (20b), gas-liquid separator (3a) (3b)
Are sequentially sucked into the compressors (2a) and (2b). Thus, each use side heat exchanger (10a) (10
b) All rooms are heated simultaneously in (10c).

In addition, in order to simultaneously cool, for example, two rooms and heat one room, one of the heat source side switching valves (6a) is opened and the other heat source side switching valves (6a), (7a), (7b) are closed. One switching valve (13a) (13c) of user side unit (9a) (9c)
Is closed and the other switching valves (14a) and (14c) are opened, and one switching valve (13b) of the heating use side unit (9b) is opened, the other switching valve (14) is closed, and the control valve (2) is closed.
When the valve opening degree of 1) is closed by a signal from the controller (22), the refrigerant discharged from one of the compressors (2a) discharges the discharge pipe (19).
a), the high-pressure gas refrigerant pipe (16), the heat source side switching valve (6a), and then flow to only one heat source side exchanger (3a) and discharge from the other compressor (2b) through the discharge pipe (19b). The refrigerant that has flowed into the high-pressure gas refrigerant pipe (12) is blocked by the control valve (21) in the closed state and does not flow to the heat source side unit (4), but the switching valve (13b) of the user side unit (9b) for heating,
It flows to the use side heat exchanger (10b) and is condensed and liquefied by the use side heat exchanger (10b) and the heat source side heat exchanger (5a). Then, the refrigerant condensed and liquefied in these heat exchangers (10b) (5a) passes through the liquid pipe (18) and then goes into the use side unit (9a).
After being depressurized by the refrigerant decompressors (11a) and (11c) of (9c), the refrigerant is evaporated and vaporized by the respective use-side heat exchangers (10a) and (10c), and thereafter, each of the switching valves (14a) and (14c) Through the low pressure gas refrigerant pipe (17), and is sucked into the compressors (2a) (2b) sequentially through the suction pipes (20a) (20b) and the gas-liquid separators (3a) (3b). Thus, one room is heated by the clothing-side heat exchanger (10b) acting as a condenser, and two rooms are cooled by the other utilization-side heat exchangers (10a) (10c) acting as an evaporator.

As described above, in the simultaneous cooling and heating operation, the control valve (21) is used because only the high-pressure refrigerant pressure of the use side unit (9b) needs to be kept high to increase the heating capacity of the use side unit (9b). Is closed and the high-pressure medium pressure of the use side unit (9b) is maintained high only by the compressor (2b). To maintain this, the controller (22) includes the use side heat exchanger (10
The operation frequency of the compressor (2b) is variably controlled by inputting the detection signal of the refrigerant temperature and the high-pressure refrigerant pressure of b). At the same time, the detection signal of the refrigerant temperature and the low-pressure refrigerant pressure of the use-side heat exchangers (10a) (10c) of the use-side units (9a) (9c) operating in the cooling operation is input to the controller (22). Thus, the compressor (2b) is configured to compensate for the shortage of the cooling capacity of the use-side units (9a) (9c) by the operation of the compressor (2a), which cannot be covered by the heating operation of the use-side unit (9b) alone. )
Is variably controlled. Moreover, the high-pressure refrigerant pressure required for the cooling operation is controlled by the use side unit (9a) (9
c) The pressure of the high-pressure refrigerant of the compressor (2a) can be reduced because the pressure of the refrigerant can be supplied to the liquid refrigerant pipe (18) from the heat source side heat exchanger (5a) to the extent that the refrigerant does not run out of gas (gas shortage). Machine (2b)
Need not be as high as the high pressure refrigerant pressure of the compressor (2
The operation efficiency is improved by the pressure drop resulting from lowering the high pressure refrigerant pressure in a).

This operation efficiency is remarkably improved in the cooling / heating operation mainly in cooling, in which the number of the use side units is, for example, eight, one of which is in the heating operation, and the seven is in the cooling operation.

In the simultaneous cooling and heating operation, when the cooling load is large, the operating frequency of the compressor (2a) is increased by the control signal from the controller (22) to increase the operating capacity. If the capacity is still insufficient, the control valve is used. By slightly opening (21) and raising the operating frequency of the compressor (2b) to increase the operating capacity, the compressor ( Part of the high-pressure refrigerant gas discharged from 2b) is guided to the heat-source-side heat exchanger (5a) via the control valve (21), so that a desired cooling and heating capacity can be obtained.

In this way, each of the user-side units (9a) (9b) (9c) has its own switching valve (6a) (7a), (6b) (7b), (13a) (1
4a), (13b), (14b), (13c), (14c) opening / closing and control of the valve opening of the control valve (21) enable the cooling and heating operation arbitrarily. Since heat recovery is performed in each of the use side heat exchangers (10a) (10b) (10c) acting as an evaporator and a condenser, the operation efficiency is improved.

FIG. 2 shows a second embodiment of the present invention. The difference from the first embodiment is that two compressors (2a) (2
A single variable capacity compressor (2) having an intermediate discharge port (23) is provided instead of the intermediate discharge port (2).
3) and an intermediate discharge pipe (2) connecting the high-pressure gas refrigerant pipe (16).
4) and high pressure gas refrigerant pipe (16) between the main discharge pipe (25)
Is provided with a refrigerant main control valve (26) and an electric refrigerant sub-control valve (27) in the intermediate discharge pipe (24).

Incidentally, (28) is a controller for controlling the opening and closing of the main control valve (26) and the sub-control valve (27), (29) is a rotor, and (30) is a partition vane.

The cooling operation in all rooms, the heating operation in all rooms, and the simultaneous operation in cooling and heating are the same as those in the first embodiment described above. The supplementary explanation of the operation of the sub control valve (27) will be given.

Main control valve (26) for all-room cooling operation and all-room heating operation
Is opened and the sub-control valve (27) is closed, so that the high-pressure gas refrigerant discharged from the main discharge pipe (25) is supplied to the heat source side unit (4) during the cooling operation in all rooms, and the utilization side unit ( It flows to 9a), (9b) and (9c) in the same manner as in the first embodiment, and is returned to the compressor (2) via the suction pipe (20) and the gas-liquid separator (3).

In the simultaneous cooling / heating operation in which one room is heated and two rooms are cooled, the main control valve (26) is closed and the sub-control valve (27) is opened, so that the main discharge port (31) is connected to the main discharge pipe (25). ) Is discharged to the use side unit (9b) for heating operation, and from the intermediate discharge port (23) to the intermediate discharge pipe (2).
The medium-pressure gas refrigerant discharged via 4) flows to the heat source side unit (4) in the same manner as in the first embodiment, and the compressor (2)
Is returned through the suction pipe (20) and the gas-liquid separator (4).

In the second embodiment, the pressure and flow rate of the high-pressure gas refrigerant discharged from the main discharge port (31) and the discharge pressure from the sub-discharge port (23) are adjusted by adjusting the valve opening of the sub-control valve (27). Since the pressure and flow rate of the medium-pressure gas refrigerant are controlled in inverse proportion,
The main control valve (26) may be a simple on-off valve.

FIG. 3 shows a third embodiment of the present invention. The difference from the first embodiment is that the compressor (2a) and the heat source side heat exchanger (5
a) and the compressor (2b) and the heat source side heat exchanger (51b) having a smaller capacity than the heat source side heat exchanger (5a) are housed in the heat source side units (4a) and (4b), respectively. The point is that a control valve (34) including a pressure regulating valve (32) and an electromagnetic on-off valve (33) is provided in the high-pressure gas refrigerant pipe of the heat source side unit (4b).

The cooling operation in all rooms, the heating operation in all rooms, and the simultaneous operation in heating and cooling are the same as those in the first embodiment described above. The operation of the valve (33) will be supplementarily described.

The solenoid on-off valve (3
By opening 3) and closing the pressure control valve (32), the high-pressure gas refrigerant discharged from the discharge pipe (19b) is supplied to the heat source side unit (4) during all-room cooling operation, and to the utilization side unit during all-room heating operation. (9a), (9b) and (9c) flow in the same manner as in the first embodiment, and the compressors (2a) and (2b) have suction pipes (20).
a) (20b), returned via gas-liquid separator (4a) (4b).

In the simultaneous cooling and heating operation in which one chamber is heated and two chambers are cooled, the high-pressure gas refrigerant discharged from the compressor (2b) is heated by closing the pressure regulating valve (32) and the solenoid on-off valve (33). To the operating user unit (9b) and to the compressor (2a)
The high-pressure gas refrigerant discharged from the compressor flows into the heat source side unit (4) in the same manner as in the first embodiment, and is returned to the compressor (2) via the suction pipe (20) and the gas-liquid separator (3). .

Even during such simultaneous cooling and heating operation, the pressure regulating valve (3
By slightly opening 2), a part of the refrigerant discharged from the compressor (2b) is guided to the heat source side heat exchangers (5a) and (51b) as in the first embodiment.

In the first and second embodiments, the heat source side heat exchangers (5a) and (5b) may have the same capacity or different capacities as in the third embodiment. ) May be one in which an electromagnetic on-off valve and a capillary are connected in parallel.

(G) Effects of the Invention According to the present invention, simultaneous cooling and heating operations of a plurality of use-side units as well as simultaneous cooling and heating operations can be freely selected and performed by an arbitrary use-side unit.
Moreover, the high-pressure gas refrigerant pipe is provided with a refrigerant control valve at an intermediate position between the plurality of compressors, or a refrigerant main control valve at an intermediate position between the discharge pipes of the compressor, and a refrigerant sub-control valve at at least one of the discharge pipes. The control valve is closed or slightly opened at the time of simultaneous heating and cooling operation, so that the high-pressure refrigerant pressure of only the use-side unit heating by one of the compressors is maintained at a high level and the desired heating capacity is maintained. Along with
The pressure of the refrigerant discharged from the other compressor need only be such that the use-side unit performing the cooling operation does not run out of gas, and the operating efficiency can be improved by the amount of the pressure drop by reducing the high-pressure refrigerant pressure.

[Brief description of the drawings]

FIG. 1 is a refrigerant circuit diagram of an air conditioner showing a first embodiment of the present invention, FIG. 2 is a refrigerant circuit diagram of an air conditioner showing a second embodiment of the present invention, and FIG. FIG. 9 is a refrigerant circuit diagram of an air conditioner showing a third embodiment of the present invention. (2) (2a) (2b) Compressor, (5a) (5b) (51b)
…… The heat source side heat exchanger, (6a) (7a), (6b) (7b),
(13a) (14a), (13b) (14b), (13c) (14c) ...
Switching valve, (8a) (8b), (11a) (11b) (11c) ... Refrigerant decompressor, (10a) (10b) (10c) ... User side heat exchanger, (16) ... High-pressure gas refrigerant Pipe, (17) ... low-pressure gas refrigerant pipe, (18) ... liquid refrigerant pipe, (19a) (19b), (24)
(25) ... discharge pipe, (20) (20a) (20b) ... suction pipe,
(21), (34) ... refrigerant control valve, (26) ... refrigerant main control valve, (27) ... refrigerant sub-control valve.

Claims (2)

(57) [Claims] An air conditioner in which a compressor, a heat source side heat exchanger, and a plurality of use side heat exchangers are connected by a refrigerant pipe.
A plurality of compressors are provided, and a high-pressure gas refrigerant pipe to which the discharge pipe of each compressor is connected and a low-pressure gas refrigerant pipe to which the suction pipe is connected are connected to one end of each of the heat source side heat exchanger and the use side heat exchanger. And the other end of the heat source side heat exchanger and the other end of the use side heat exchanger are connected by a liquid refrigerant pipe via a refrigerant decompressor, and a plurality of high pressure gas refrigerant pipes are connected to the high pressure gas refrigerant pipe. An air conditioner, wherein a refrigerant control valve is provided at an intermediate position of the compressor. 2. An air conditioner in which a compressor, a heat source side heat exchanger, and a plurality of use side heat exchangers are connected by refrigerant pipes.
A compressor is provided with a plurality of discharge pipes, and a high-pressure gas refrigerant pipe connected to each discharge pipe and a low-pressure gas refrigerant pipe connected to a suction pipe of the compressor are connected to a heat source side heat exchanger and a use side heat exchanger. And the other end of the heat source side heat exchanger and the other end of the use side heat exchanger are connected by a liquid refrigerant pipe via a refrigerant pressure reducer, and the high pressure gas refrigerant pipe An air conditioner, wherein a refrigerant main control valve is provided at an intermediate position between a plurality of discharge pipes, and a refrigerant sub-control valve is provided on at least one of the discharge pipes.