JP2804622B2 - Air conditioner - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner, and more particularly, to an air conditioner in which an interior part and a perimeter part in a building can be individually cooled or heated by a plurality of use side heat exchangers. The present invention relates to an air conditioner that has been manufactured.

[Conventional technology]

Generally, the interior of a building is divided into a central interior section and a perimeter section facing the outer wall. In recent years, the period of air conditioning in the interior has been increasing with the increase in OA equipment etc. placed in the central interior.In recent years, the perimeter facing the outer wall has been heated in the middle period etc. While cooling the central interior.

Therefore, conventionally, in accordance with the recent trend, a plurality of use-side heat exchangers are connected to the heat-source-side heat exchanger, and these use-side heat exchangers are arranged separately in the interior and perimeter sections of the building. And a switching valve for switching the refrigerant flow path for operating the heat source side heat exchanger and the use side heat exchanger as a condenser or an evaporator, and the interior part and the perimeter part are switched by switching the switching valve. Are individually cooled or heated (JP-A-63-27963).

By the way, the power demand at midnight is less than the power demand at daytime, and the power cost at midnight is cheaper. Then, it is economically desirable to perform a heat storage operation using low-cost power at midnight and release the heat stored during this operation during daytime operation to reduce daytime power consumption.

[Problems to be solved by the invention]

However, in a multi-type in which a cooling operation and a heating operation can be individually performed by a plurality of use-side units, an air conditioner that can perform a heat storage operation and reduce power consumption during daytime operation has not been proposed. .

Therefore, an object of the present invention is to provide a multi-type air conditioner that can solve the above-described problems of the conventional technology and can reduce power consumption during daytime operation.

[Means for solving the problem]

In order to achieve the above object, the present invention provides a compressor, a plurality of heat source side heat exchangers, and a plurality of utilization side heat exchangers, and a high pressure pipe connected to a refrigerant discharge pipe of the compressor, The low-pressure pipe and the liquid pipe connected to the refrigerant suction pipe of the compressor are each branched, and the high-pressure branch pipe and the low-pressure branch pipe have a heat source side exchanger and a use side heat exchanger connected to each branch pipe. And a switching valve for switching the refrigerant flow path for operating as a condenser or an evaporator, respectively, and the liquid branch pipes are connected to the heat source side heat exchanger and the use side heat exchanger via the refrigerant pressure reducer, respectively. In the connected air conditioner, at least one of the plurality of heat source side heat exchangers is provided in the heat storage tank, and the heat storage heat exchanger in the heat storage tank is replaced with another heat source side heat exchanger. The heat exchanger for storage and the heat exchanger for heat storage are arranged in a branch pipe between the heat exchanger for use in heat storage and the heat exchanger for use in heat storage. The connecting tube between the switching valve of the coolant channel switching, via an auxiliary branch pipe having an auxiliary switching valve,
It is characterized by being connected to a liquid pipe.

(Operation)

According to the present invention, first, at midnight when power demand is small, a heat storage operation is performed using, for example, one heat source side heat exchanger and a heat storage heat exchanger. In this case, the switching valve for switching the refrigerant flow path is switched so that the heat source side heat exchanger functions as a condenser and the heat storage heat exchanger functions as an evaporator. When the heat storage heat exchanger acts as an evaporator,
The heat storage water in the heat storage tank accommodating the heat storage heat exchanger is cooled and becomes cold water or ice. That is, by performing the heat storage operation using the low-cost midnight power, cold heat is stored in the heat storage water in the heat storage tank. Next, during the cooling operation in the daytime,
The cold stored in the heat storage tank is released. In this case, the switching valve for switching the refrigerant flow path is switched so that the heat source side heat exchanger and the heat storage heat exchanger function as a condenser, and the use side heat exchanger functions as an evaporator. When the heat storage heat exchanger functions as a condenser, a liquid refrigerant flows into the condenser. The liquid refrigerant is supercooled by receiving the release of the cold stored in the heat storage tank. Thus, during daytime cooling operation, the use side heat exchanger acts as an evaporator,
Cooling air is sent from there, but during the refrigeration cycle, the liquid refrigerant is supercooled by the heat storage heat exchanger, so the refrigeration capacity increases by that much, and the power consumption of the compressor during the day decreases. I do.

〔Example〕

Hereinafter, an embodiment of an air conditioner according to the present invention will be described with reference to the accompanying drawings.

In FIG. 1, reference numeral 1 denotes a heat source side unit,
Use side units 5a to 5d are connected to the heat source side unit 1 through unit piping 3. The heat source side unit 1 incorporates a variable capacity (inverter) compressor 21, a gas-liquid separator 22, and heat source side heat exchangers 23A to 23C, and these heat source side heat exchangers 23A to 23C. Are connected to first switching valves 25A to 25C and second switching valves 26A to 26C. The first switching valves 25A to 25C are branched high-pressure gas pipes 32A to 3C.
2C, is connected to the refrigerant discharge pipe 27 of the compressor 21 and
Are connected to the refrigerant suction pipe 28 of the compressor 21 via branch low-pressure gas pipes 33A to 33C.

The unit-to-unit pipe 3 includes a liquid pipe 31, a high-pressure gas pipe 32, and a low-pressure gas pipe 33. One end of the liquid pipe 31 is branched, and each of the branched liquid pipes 31A to 31C is provided with an electric expansion valve or the like. Are connected to the heat source side heat exchangers 23A to 23C through the refrigerant decompressors 29A to 29C, respectively, and the other end of the liquid pipe 31 is branched, and the respective branched liquid pipes 31a to 31d are electrically operated expansion valves. Refrigerant pressure reducer 35, etc.
They are connected to the four use side heat exchangers 51a to 51d via a to 35d, respectively. The high-pressure gas pipe 32 is connected to the refrigerant discharge pipe 27, and the low-pressure gas pipe 33 is connected to the refrigerant suction pipe.

The four use side heat exchangers 51a to 51d are incorporated in each of the use side units 5a to 5d described above. Each of the use side heat exchangers 51a to 51d is connected to a low pressure gas switching valve 37a to 37d and a high pressure gas switching valve 38a to 38d, and the low pressure gas switching valve 37a to 37d is connected to a low pressure gas pipe 33. Are connected to branch low-pressure gas pipes 33a to 33d. High pressure gas switching valve 38a-3
8d is a branch high-pressure gas pipe 32a-3 branched from the high-pressure gas pipe 32.
Connected to 2d. The above configuration is almost the same as the conventional one.

Thus, according to this embodiment, the heat source side heat exchanger 23A
23C, one heat source side heat exchanger 23C (hereinafter referred to as a heat storage heat exchanger) is housed in a heat storage tank 60, and the heat storage tank
60 is filled with heat storage water. This heat storage heat exchanger 23C is connected between the other heat source side heat exchangers 23A and 23B and the use side heat exchangers 51a to 51d, and a connecting pipe 61 of the heat storage heat exchanger 23C has an auxiliary pipe. The liquid pipe 31 is connected via a branch pipe 62 and an auxiliary switching valve 63 formed of a three-way valve.

 Next, the operation of this embodiment will be described.

According to this system, heat storage operation can be performed. That is, late-night power is cheaper than daytime power. Therefore, using low-cost electricity at midnight,
By keeping the heat storage water in the heat storage tank 60 as cold water or ice, and releasing the cold stored as cold water or ice during daytime cooling operation, it is possible to reduce the use of electric power during daytime cooling operation. .

For example, when performing heat storage operation using the heat source side heat exchanger 23B (or the heat source side heat exchanger 23A) and the heat storage heat exchanger 23C at midnight, the first switching valve 25B is opened. Then, the second switching valve 26B is closed, the first switching valve 25C is closed, and the second switching valve 26C is opened. Of course, the other switching valves 25A and 26A, the low pressure gas switching valves 37a to 37d, and the high pressure gas switching valves 38a to 38d are all closed, and the auxiliary switching valve 63 is closed to shut off the flow to the auxiliary branch pipe 62. .

In this state, when the variable capacity (inverter) compressor 21 is driven with a low capacity, the refrigerant discharged from the compressor 21 is sequentially transmitted to the refrigerant discharge pipe 27, the first switching valve 25B, and the heat source side heat exchanger 23B. After flowing and condensed and liquefied here, it reaches the refrigerant decompressor 29C via the branch liquid pipe 31B, the liquid pipe 31, and the branch liquid pipe 31C. Then, the pressure is reduced here, and evaporates and evaporates in the heat storage heat exchanger 23C, and is sequentially compressed through the second switching valve 26C, the branch low-pressure gas pipe 33C, the low-pressure gas pipe 33, the refrigerant suction pipe 28, and the gas-liquid separator 22. Machine 21.

That is, when the heat storage operation is performed, the heat storage heat exchanger 23C acts as an evaporator, and the heat storage water in the heat storage tank 60 becomes cold water or ice, where cold heat is stored.

Next, during the daytime cooling operation, the cold stored in the heat storage tank 60 is released.

To perform the cooling operation, the first switching valves 25A, 25B connected to the heat source side heat exchangers 23A, 23B are opened, and the second switching valve 26 is opened.
Close A and 26B. Further, the low pressure gas switching valves 37a to 37d connected to the use side heat exchangers 51a to 51d are opened, and the high pressure gas switching valves 38a to 38d are closed.

Then, the first switching valve 25C and the second switching valve 26C are closed, the auxiliary switching valve 63 is opened, and the flow from the branch liquid pipes 31A and 31B to the auxiliary branch pipe 62 is opened.

When the switching valve is opened / closed in this manner, the refrigerant discharged from the compressor 21 flows through the refrigerant discharge pipe 27, the first switching valves 25A and 25B,
After flowing sequentially to the heat source side heat exchangers 23A and 23B and condensed and liquefied here, they pass through the branch liquid pipes 31A and 31B, further pass through the auxiliary switching valve 63 and the auxiliary branch pipe 62, and pass through the heat storage heat exchanger 23C. Inflow.

The heat storage water in the heat storage tank 60 has already been turned into cold water or ice by midnight operation, and the cold heat is stored therein, so that the liquid refrigerant flowing into the heat storage heat exchanger 23C passes there. Cooled.

The supercooled liquid refrigerant passes through the branch liquid pipe 31C, the liquid pipe 31, and the branch liquid pipes 31a to 31d, and passes through the respective refrigerant decompressors 35a.
It is distributed to ~ 35d and decompressed. After that, it is evaporated and vaporized in the use-side heat exchangers 51a to 51d, and the low-pressure gas switching valves 37a to 37d,
Branch low-pressure gas pipes 33a to 33d, low-pressure gas pipe 33, refrigerant suction pipe 28
Then, it is sucked into the compressor 21 through the gas-liquid separator 22 in order.

That is, in the case of cooling operation, all the use side heat exchangers
51a to 51d function as an evaporator and cool air is sent out therefrom.According to this embodiment, during the refrigeration cycle, the liquid refrigerant is supercooled by the heat storage heat exchanger 23C. Accordingly, the refrigeration capacity is increased, and the power consumption of the compressor 21 during the day can be reduced.

Therefore, according to this embodiment, an effect is obtained that the demand for power at midnight and daytime can be leveled.

In this embodiment, all the use side heat exchangers 51a to 51d
Accordingly, in the case of simultaneous heating, the opening and closing operation of the valve is reversed from that in the case of simultaneous cooling described above. That is, the heat source side heat exchanger 23
A, the first switching valves 25A, 25B connected to 23B are closed, and the second
Open the switching valves 26A and 26B. In addition, the use side heat exchanger 51a ~
Close the low pressure gas switching valves 37a to 37d connected to 51d,
The high pressure gas switching valves 38a to 38d are opened. In this case,
Naturally, the switching valves 25C and 26C are closed, and all the systems related to the heat storage heat exchanger 23C are separated from the system.

When the switching valve is opened and closed in this way, the refrigerant discharged from the compressor 21 sequentially passes through the refrigerant discharge pipe 27, the high-pressure gas pipe 32, the branch high-pressure gas pipes 32a to 32d, and the high-pressure gas switching valves 38a to 38d, It is distributed to each use side heat exchanger 51a-51d.
After being condensed and liquefied here, the pressure is reduced by the refrigerant decompressors 35a to 35d, and the liquids are joined by the liquid pipe 31 through the branch liquid pipes 31a to 31d. After being evaporated and vaporized in the heat source side heat exchangers 23A and 23B, the refrigerant is sucked into the compressor 21 through the second switching valves 26A and 26B, the refrigerant suction pipe 28 and the gas-liquid separator 22 in order.

That is, when heating at the same time, all the use-side heat exchangers 51a to 51d act as condensers, from which warm air is sent.

Further, in this embodiment, by opening and closing the switching valve, the use side heat exchangers 51a to 51d can be individually used as evaporators or condensers, and can be individually cooled and heated.

For example, in the case where only the right-side use-side heat exchanger 51d among the use-side heat exchangers 51a to 51d is used for cooling and the rest is used for heating, the first one connected to the heat-source-side heat exchangers 23A and 23B is used. The switching valves 25A and 25B are closed, and the second switching valves 26A and 26B are opened.
Further, the low-pressure gas switching valve 37d and the high-pressure gas switching valve 38a to 38c connected to the use side heat exchangers 51a to 51d are opened, and the low-pressure gas switching valves 37a to 37c and the high-pressure gas switching valve 38d are opened. To close.

According to this, the refrigerant discharged from the compressor 21 is supplied to the refrigerant discharge pipe 27, the high-pressure gas pipe 32, the branch high-pressure gas pipes 32a to 32c, the high-pressure gas switching valves 38a to 38c, and the use side heat exchangers 51a to 51c. And sequentially condensed and liquefied in each of the heat exchangers 51a to 51c. The refrigerant liquefied in the use side heat exchangers 51a to 51c is
The refrigerants are joined at 31, a part of the refrigerant is distributed to the refrigerant decompressors 29A and 29B, and the remaining refrigerant is distributed to the refrigerant decompressor 35d, where the pressure is reduced.

Thereafter, the refrigerant evaporated and vaporized in the heat source side heat exchangers 23A and 23B passes through the switching valves 26A and 26B, and the refrigerant evaporated and vaporized in the use side heat exchanger 51d is switched to a low pressure gas switching valve 37d and a branch low pressure gas pipe 33b. , Through the low-pressure gas pipe 33 in sequence, and further into the refrigerant suction pipe 2
The liquid is sucked into the compressor 21 via the gas and the gas-liquid separator 22.

That is, when only the right end is used for cooling and the rest is used for heating, the use-side heat exchangers 51a to 51c are operated as condensers, and the use-side heat exchangers 51d are sent out while supplying warm air therefrom.
Acts as an evaporator, from which cool air is delivered.

The above describes an example in which one unit is cooled and the remaining unit is heated. However, only the right-side use side exchanger 51d is heated and the remaining unit is cooled, or two units are cooled and the remaining unit is heated. Thus, it is possible to operate any of them.

 FIG. 2 shows another embodiment.

In this embodiment, two heat source side heat exchangers 23D and 23E (hereinafter referred to as heat recovery heat exchangers) are added, and one of the heat recovery heat exchangers 23D is housed in a hot water supply heat storage tank 65. The other heat recovery heat exchanger 23E is housed in a waste heat tank 66. In the waste heat tank 66, for example, waste heat of a factory is recovered and stored.

To explain the operation of this embodiment, by performing heat storage operation at midnight, the waste heat water in the heat storage tank 60 is turned into high-temperature water by utilizing the waste heat of the factory stored in the waste heat tank 66 and the like. In the meantime, during the daytime heating operation, the stored heat is released into the storage heat tank 60 to reduce the power consumption during the day.

To explain this in detail, first, the heat recovery heat exchanger 23
The storage operation is performed using E and the heat exchanger for livestock heat 23C.

In this case, the first switching valve 25E is closed, the second switching valve 26E is opened, the first switching valve 25C is opened, and the second switching valve 26C is closed. Of course, other switching valves 25
A, 25B, 25D, 26A, 26B, 26D, low-pressure gas switching valves 37a to 37d,
The high-pressure gas switching valves 38a to 38d are all closed, and the auxiliary switching valve 63 is closed to shut off the flow to the auxiliary branch pipe 62.

In this state, when the variable capacity (inverter) compressor 21 is driven with a low capacity, the refrigerant discharged from the compressor 21 is cooled by the refrigerant discharge pipe 27, the high pressure gas pipe 32, the branch high pressure gas pipe 32C, and the first high pressure gas pipe 32C.
Through the switching valve 25C and the connection pipe 61, and is distributed to the heat exchanger for livestock heat 23C. After being condensed and liquefied here, the pressure is reduced by the refrigerant pressure reducer 29C, and then reaches the heat recovery heat exchanger 23E via the branch liquid pipe 31C, the liquid pipe 31, and the branch liquid pipe 31E. Here, the refrigerant is evaporated and vaporized and then sucked into the compressor 21 through the second switching valve 26E, the branch low-pressure gas pipe 33E, the refrigerant suction pipe 28, and the gas-liquid separator 22 in that order.

In other words, when the heat storage operation is performed, the heat recovery heat exchanger 23E functions as an evaporator, and the heat storage heat exchanger 23C functions as a condenser. Waste heat and the like are collected, and the animal heat water in the animal heat tank 60 becomes high-temperature water, where it is heated.

In this way, the heat stored in the storage tank 60 is released during the daytime heating operation.

To perform the heating operation, the first switching valves 25A to 25C connected to the heat source side heat exchangers 23A to 23C are closed, and the second switching valve 26 is closed.
Open A ~ 26C. In addition, the low-pressure gas switching valves 37a to 37d connected to the use side heat exchangers 51a to 51d are closed, and the high-pressure gas switching valves 38a to 38d are opened. In this case, as a matter of course, the first switching valves 25D, 25E and the second switching valves 26D, 26E, etc. are closed, and all the systems related to the heat recovery heat exchangers 23D, 23E are
Disconnect from the system.

When the switching valve is opened and closed in this way, the refrigerant discharged from the compressor 21 sequentially passes through the refrigerant discharge pipe 27, the high-pressure gas pipe 32, the branch high-pressure gas pipes 32a to 32d, and the high-pressure gas switching valves 38a to 38d, It is distributed to each use side heat exchanger 51a-51d.
After being condensed and liquefied here, the pressure is reduced by the refrigerant decompressors 35a to 35d, the liquids are joined by the liquid pipe 31 through the branch liquid pipes 31a to 31d, and then, through the branch liquid pipes 31A to 31C and the refrigerant pressure reducers 29A to 29C,
After being evaporated and vaporized in the heat source side heat exchangers 23A to 23C, the refrigerant is sucked into the compressor 21 through the second switching valves 26A to 26C, the refrigerant suction pipe 28 and the gas-liquid separator 22 in order.

That is, when heating at the same time, all the use-side heat exchangers 51a to 51d act as condensers, and warm air is sent out therefrom.According to this embodiment, during the refrigeration cycle,
Since the livestock heat exchanger 23C is used as a heating heat source,
As a result, the heating capacity is increased and the power consumption of the compressor 21 in the daytime can be reduced, so that the effect of leveling the power demand in the middle of the night and in the daytime can be obtained.

 Next, the function and effect of the hot water supply heat tank 65 will be described.

During the cooling operation, as described above, the use-side heat exchanger 51
a to 51d function as an evaporator, and cool air is sent out from the evaporator. In this case, since the heat source side heat exchanger 23 functions as a condenser, heat is released therefrom.

Thus, according to this embodiment, during the cooling operation, the heat recovery heat exchanger 23D in the hot water supply / stock heat tank 65 is used as a condenser. According to this, since surplus heat in the refrigeration cycle can be recovered, if this is used as a hot water supply heat source,
High-temperature water can be easily stored in the hot-water supply heat tank 65. Since this high-temperature water may be used for factory water, it is possible to obtain effects such as extremely efficient waste heat recovery.

[Effects of the Invention] As is clear from the above description, according to the present invention, at least one heat exchanger of the plurality of heat source side heat exchangers is provided in the storage heat tank, and Is disposed between the branch between the other heat source side heat exchanger and the use side heat exchanger, and the heat storage heat exchanger and a refrigerant flow switching valve of the heat storage heat exchanger The connection pipe between the switching pipe and the switching valve is connected to the liquid pipe via an auxiliary branch pipe having an auxiliary switching valve, so that at night when power demand is low, the heat source side exchanger and the heat storage heat exchanger Can be used for heat storage operation,
If the cold heat stored in the heat storage tank by this heat storage operation is released during the daytime cooling operation, the refrigeration capacity can be increased, so that the power consumption of the daytime compressor can be reduced. Play.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a refrigerant circuit diagram showing one embodiment of an air conditioner according to the present invention, and FIG. 2 is a refrigerant circuit diagram showing another embodiment. 1 ... heat source side unit, 3 ... unit piping, 5a-5d
... Utilizing unit, 21 ... Compressor, 23A-23E ... Heat source side heat exchanger, 25A-25E ... First switching valve, 26A-26E ...
2nd switching valve, 31 ... liquid pipe, 31A to 31E, 31a to 31d ... branch liquid pipe, 32 ... high pressure gas pipe, 32A to 32E, 32a to 32d ... branch high pressure gas pipe, 33 ... low pressure Gas pipe, 33A-33E, 33a-33d
…… Branch low pressure gas pipe, 37a-37d …… Low pressure gas switching valve,
38a-38d switching valve for high-pressure gas, 51a-51d usage-side heat exchanger, 60 heat storage tank, 61 connecting pipe, 62 auxiliary branch pipe, 63 auxiliary switching valve, 65 ... hot water storage tank, 66 ... waste heat tank.

Claims (1)

(57) [Claims] A compressor, a plurality of heat source side heat exchangers, and a plurality of use side heat exchangers, wherein a high pressure pipe connected to a refrigerant discharge pipe of the compressor and a refrigerant suction pipe of the compressor are provided. The connected low-pressure pipe and the liquid pipe are branched, respectively, and the high-pressure branch pipe and the low-pressure branch pipe are provided with a heat source-side heat exchanger and a use-side heat exchanger connected to each branch pipe, respectively, in a condenser or In an air conditioner in which a switching valve for switching a refrigerant flow path for operating as an evaporator is provided, and a liquid branch pipe is connected to a heat source side heat exchanger and a use side heat exchanger via a refrigerant pressure reducer, respectively. At least one of the plurality of heat source side heat exchangers is provided in a heat storage tank, and the heat storage heat exchanger in the heat storage tank is used for heat exchange with another heat source side heat exchanger. The heat exchanger for heat storage and the refrigerant flow switching of the heat exchanger for heat storage are disposed in a branch pipe between the heat exchanger and the heat exchanger. The connecting tube between the valve, through the auxiliary branch pipe having an auxiliary switching valve, the air conditioner being characterized in that connected to the liquid pipe.