JPH028664A - Multi room type air conditioner - Google Patents

Abstract

PURPOSE:To enable a simultaneous cooling and heating operation to be carried out by a method wherein a bypassing circuit through a two-way valve is formed between an outdoor expansion valve and a heater connected to each of indoor units through a first expansion valve and a second expansion valve. CONSTITUTION:In case that an indoor unit 6a is in its heating operation and indoor units 6b and 6c are in its cooling operation under a cooling operation mode, an outdoor expansion valve 5 is opened by a predetermined opening, a first two-way valve V1a is opened, V1b and V1c are closed, a second two-way valve V2a is closed, V2b and V2c are opened, a first expansion valve EV1a is fully closed, EV1b and EV1c are opened by a predetermined opening, a second expansion valve EV2a is fully opened, EV2b and EV2c are fully closed and a bypassing circuit two-way valve BV is closed. In this way, coolant of high temperature and high pressure from an outdoor heat exchanger is fed into an indoor unit 6a and further fed to the indoor units 6b and 6c through the expansion valve EV2a, a header 20 and expansion valves EV1b and EV1c, respectively. In turn, in the case of heating operation mode, each of the valves is made reverse. In this way, it is possible to perform a simultaneous operation of the cooling and heating operations.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention provides a multi-room air conditioner using air as a heat source, which is equipped with a refrigeration cycle system μ for simultaneously performing cooling operation and heating operation for each room. This article relates to a heat pump type air conditioner.

Prior Art A conventional multi-room air conditioner having multiple indoor units has a second
As shown in the figure, a compressor 2.
Four-way valve 3. Outdoor heat exchanger4. and an indoor expansion valve 7 in the indoor unit G installed in parallel with the outdoor expansion valve 5. In addition, the indoor heat exchanger 8 is connected in parallel and connected sequentially to the ring test, thereby constructing a heat pump type refrigeration cycle. The compressor 2 has a variable capacity, and its capacity can be changed by changing the frequency of the supplied power. In addition, cooling operation and heating operation are switched by the four-way valve 3. During cooling operation, the refrigerant flows in the direction of the solid line arrow in the figure to form a cooling cycle, and during heating operation, the refrigerant flows in the direction of the broken line in the figure. A heating cycle is formed. In addition, the outdoor heat exchanger 4
．． An outdoor fan 9 and an indoor fan 10 are installed adjacent to the indoor heat exchanger 8, respectively.

In such a multi-room air conditioner, a plurality of, for example, three indoor units 6a, 6b, and 6c can be operated individually, and when only the indoor unit 6a is operated, other indoor units ( 3b and 3c, the indoor expansion valves 7b and 7c are fully closed, and the indoor blowers 10b and 10c are also stopped. At this time, the capacity of the compressor 2 is controlled by an inverter, etc.
It is possible to operate the indoor unit at a capacity corresponding to the number of operating indoor units.

Problems to be Solved by the Invention However, in the conventional example described above, the operation mode of the indoor units 6 is set to the same mode in all three rooms.
For example, even when the outside temperature is low, such as in winter, two rooms need to be heated and one room needs to be cooled, which has the disadvantage of not being able to meet the need for simultaneous heating and cooling operations.

Therefore, the present invention provides an outdoor blower whose rotation speed can be varied according to the outside temperature and the operating capacity of the indoor units for cooling and heating, and provides two two-way valves and two expansion valves for each of the plurality of indoor units. The purpose is to realize simultaneous heating and cooling operation by installing a header and forming a bypass circuit via a two-way valve between the outdoor expansion valve and the header. .

Means for Solving the Problems The technical means of the present invention for solving the above problems includes a variable capacity compressor, a four-way valve, and a rotation speed that can be varied according to the outside temperature and the operating capacity of the indoor unit for cooling and heating. An outdoor unit consisting of an outdoor blower, an outdoor heat exchanger, and an outdoor expansion valve; an indoor first two-way valve; an indoor heat exchanger; an indoor blower; an indoor second two-way valve; It is equipped with a refrigeration cycle in which a circuit is formed by connecting a plurality of indoor units in parallel, each consisting of a first expansion valve and a second indoor expansion valve.
The two-way valve is connected to the indoor second two-way valve, and the connection is between the indoor first two-way valve and the indoor heat exchanger and between the indoor second two-way valve and the indoor heat exchanger. A circuit is formed between the two by a first indoor expansion valve, a header, and a second indoor expansion valve, and a bypass circuit is formed between the outdoor expansion valve and the header via a two-way valve. It is.

For production The effect of this technical means is as follows.

First, the cooling and heating operation capacities of each indoor unit are compared, and the operation mode of the outdoor unit is determined.

In other words, when (total cooling capacity of the indoor unit) ≧ (total heating capacity of the indoor unit), the outdoor unit is in cooling operation mode, and when (total cooling capacity of the indoor unit) is less than (total heating capacity of the indoor unit), the outdoor unit is in cooling operation mode. is set to heating operation mode. The case of each operation mode of the outdoor unit will be explained below.

Outdoor unit: In case of cooling operation mode> Outdoor expansion valve: Predetermined opening degree, Indoor unit 1st two-way valve of indoor unit in warming DJ mode: Open, Indoor 2nd 2-way valve: Closed, Indoor side 2nd valve: Closed 1 expansion valve: closed, indoor second expansion valve p: fully open, indoor first two-way valve of indoor unit in cooling mode: closed, indoor second two-way valve: open, indoor first expansion valve : Predetermined, indoor side second expansion valve: Fully closed, and bypass circuit two-way valve: Closed. At this time, the high-temperature, high-pressure refrigerant sent from the outdoor heat exchanger passes through the indoor first two-way valve of the indoor unit in heating mode, flows into the indoor heat exchanger 11111, and radiates heat into the room (heating operation).

After that, it passes through the second indoor expansion valve and then through the header.
The refrigerant, which has been depressurized to a liquid or two-phase state by the first indoor expansion valve of the indoor unit in cooling mode, absorbs heat from the room in the indoor heat exchanger (cooling operation), and then passes through the second indoor two-way valve. Return to the outdoor unit via. In this case, the outdoor heat exchanger can cover the condensing capacity obtained by subtracting the condensing capacity of the indoor unit performing heating operation from the condensing capacity required for cooling the indoor unit. Therefore, the capacity of the outdoor heat exchanger is smaller than when all indoor units are in cold FjS mode.
In particular, when the outside temperature is low, by reducing the rotational speed of the outdoor fan and reducing the heat dissipation capacity of the outdoor heat exchanger, it is possible to suppress an extreme drop in the condensing pressure, that is, the compressor discharge pressure. Improves machine reliability.

However, when the indoor unit is in cooling mode for all rooms, the two-way valve of the bypass circuit is opened, and the high-temperature, high-pressure refrigerant is sent to the header, and the pressure is reduced by the first expansion valve on the indoor side of the indoor unit, resulting in a liquid or two-phase state. The resulting refrigerant returns to the outdoor unit via the indoor second two-way valve after the indoor heat exchanger absorbs heat from the room (cooling operation).

Outdoor unit: in heating operation mode> Outdoor expansion valve: specified opening, valve to the indoor cylinder of the indoor unit in heating mode: closed, indoor second two-way valve: open, indoor first expansion Valve: specified, indoor second expansion valve: fully open, valve 'V; J + indoor second two-way valve: closed, indoor first expansion valve: fully closed, Second indoor expansion valve: Set as specified, and two-way valve of bypass circuit: Closed. At this time, the high-temperature, high-pressure refrigerant sent from the outdoor heat exchanger passes through the indoor second two-way valve of the indoor unit in heating mode, flows into the indoor heat exchanger, and radiates heat into the room (heating operation).

After that, it passes through the first expansion valve on the indoor side and via the header.
The refrigerant, which has been depressurized by the second indoor expansion valve of the indoor unit in cooling mode and becomes a liquid or two-phase state, absorbs heat from the room in the indoor heat exchanger (cooling operation), and then enters the indoor cylinder with a diversion valve. return to the outdoor unit via the

In this case, the outdoor heat exchanger can cover the condensing capacity obtained by subtracting the condensing capacity of the indoor unit performing heating operation from the condensing capacity required for cooling the indoor unit. Therefore, the capacity of the outdoor heat exchanger is smaller than when all indoor units are in cooling mode, especially when the outside temperature is low.
By lowering the rotational speed of the outdoor blower and suppressing the heat dissipation capacity in the outdoor heat exchanger, it is possible to suppress the condensing pressure, that is, the compressor suction pressure, and [II: Small pressure], thereby suppressing the extreme drop in the compressor pressure. reliability is improved.

As shown in [2] above, an outdoor heat exchanger whose capacity can be varied according to the outside temperature and the cooling and heating operating capacity of the indoor unit is installed in the outdoor unit, and headers are installed in multiple indoor units, Two-way valves and expansion valves installed in each indoor unit, and
By controlling the two-way valve installed in the bypass circuit between the outdoor expansion valve and the header as described above, it is possible to realize simultaneous heating and cooling operations throughout the year.

Embodiment Hereinafter, an embodiment of the present invention will be described based on the accompanying drawings, and the same components as those in the conventional art will be denoted by the same reference numerals, and detailed explanation thereof will be omitted.

FIG. 1 is a refrigeration cycle diagram of a heat pump type air conditioner according to an embodiment of the present invention. The heat pump type air conditioner of this embodiment has a variable capacity compressor, 2° four-way valve, 3. Outdoor heat exchanger4. An outdoor unit 1 consisting of an outdoor side blower 9° and an outdoor side expansion valve 5, a direction valve Vl on the indoor side cylinder, and an indoor side heat exchanger 8.
Indoor blower 10, indoor second two-way valve V2. Indoor side 1st
Expansion valve IEV 1 and indoor second expansion valve IEV2
A refrigeration cycle is provided in which three indoor units 6 consisting of the following are connected in parallel to form a main circuit. Outdoor ventilation! 39 can vary the rotation speed in several stages depending on the outside temperature and the operating capacity of the indoor unit for cooling and heating. Outdoor unit 1 and each indoor unit 6
a, 6b, (3c is a valve on the indoor side cylinder ■l a J V
1 b, V lc and the second indoor two-way valve V2a.

V2b and V2c, and the indoor cylinder is connected between the one-way valves Vla to Vlc and the indoor heat exchangers 8a to 8C, and the second indoor two-way valves V2a to V2c and the indoor heat exchanger. 8a to 8c, the indoor first expansion valve EV1a"1E
V1c, a common header 20 for each indoor unit. A circuit is formed between the second indoor expansion valve IEV2a and IEV2c, and a bypass circuit is formed between the outdoor expansion valve 5 and the header 20 via the two-way valve BV.

Next, the operation of the configuration of this embodiment will be explained.

First, the capacity of cooling and heating operations is compared based on the operation mode set by the controller of each indoor unit, and the operation mode of the outdoor unit is determined. In other words, when (total cooling capacity of the indoor unit) ≧ (total heating capacity of the indoor unit), the outdoor unit goes into cooling operation mode, and when (total cooling capacity of the indoor unit) < (total heating capacity of the indoor unit), the outdoor unit goes into the cooling mode. Set the machine to heating mode. Then, depending on the operation mode of the outdoor unit, the outdoor M'A valve 5. Indoor side first two-way valve Vla to Vlc, indoor side second two-way valve V2
a to V2c, indoor first expansion valve EV1a''EVlc, indoor second expansion valve [EV2a-EV2c+ and two-way valve B
The following operation is performed by controlling the opening/closing or opening degree of V.

For example, indoor unit 6a: heating mode, indoor unit 6b, (3
c: The case of cooling mode will be explained.

Outdoor expansion valve 5: Predetermined opening degree, indoor unit 6a in heating mode
Directional valve Via: Open, indoor second two-way valve V2a to the indoor cylinder
: Closed, 1st indoor expansion valve IEVIa: Fully open, 2nd indoor expansion valve
Expansion valve IEV2a: fully open, indoor unit 6b in cooling mode
, 6c, one-way valve Vlb, Vlc: closed, second indoor two-way valve V2b in the indoor cylinder.

V2c: Open, indoor 1st I111! Zhang Ben Evtb,r:
vIC: Predetermined, indoor second expansion valve E V 2 b , E
V 2 C: Fully closed, bypass circuit two-way valve B■: Closed.

At this time, the high-temperature, high-pressure refrigerant sent from the outdoor heat exchanger 4 passes through the valve Via to the indoor cylinder of the indoor unit 6a in the heating mode, flows into the indoor heat exchanger 8a, and radiates heat into the room (heating driving). Thereafter, the refrigerant passes through the second indoor expansion valve V2a, passes through the header 20, and is depressurized into a liquid or two-phase state by the indoor first S expansion valves Vlb and Vlc of the indoor units 6b and 6c in the cooling mode. After the indoor heat exchanger 8b absorbs heat from the room at 8 degrees (cooling operation), it returns to the four-way valve 3 in the outdoor unit 1 via the second indoor two-way valve V 2 b + V 2 c.

However, if the indoor units 6a to 6C are in the indoor cooling mode,
The two-way valve B■ of the bypass circuit: 17i1 sends high-temperature, high-pressure refrigerant to the header 20, and the refrigerant that has been depressurized and turned into a liquid or two-phase state by the indoor first expansion valves Via to Vlc of the indoor units 6a to 6c is , After the indoor heat exchangers 8a to 8c absorb heat from the room (cooling operation), the indoor second two-way valve V2a
~ Return to the four-way valve 3 in the outdoor unit 1 via V2c.

In this case, the outdoor heat exchanger 4 can cover the condensing capacity obtained by subtracting the condensing capacity of the indoor unit 6a, which is in heating operation, from the condensing capacity required for cooling the indoor units 6b and 6c. Therefore, the capacity of the outdoor heat exchanger 4 is smaller than when all the indoor units are in the cooling mode, so especially when the outside temperature is low, the rotational speed of the outdoor fan 9 is lowered and the outdoor heat exchanger 4 is By keeping the heat dissipation capacity low, it is possible to suppress an extreme drop in the condensing pressure, that is, the compressor suction pressure, and the discharge pressure, and the reliability of the compressor is improved.

For example, indoor unit 6a: cooling mode, indoor units 6b, 6c
: Explain the case of heating mode.

Outdoor expansion valve 5: Predetermined opening degree, indoor heating mode 4!1
The two-way valves Vlb and V'IC in the indoor cylinders of 6b and 6c are closed, and the second indoor two-way valves V2b and V2c are open.

Indoor side first expansion valve rEV1b, EVlc: predetermined, indoor side second expansion valve EV2b, EV2c: fully closed, open to indoor cylinder of indoor unit 6a in cooling mode Valve ■1a: open, indoor side second two way Valve V2a: closed, first indoor expansion valve IEV1a: fully closed, second indoor expansion valve EV2a: predetermined, and two-way valve B2 of the bypass circuit: closed. At this time, the high-temperature, high-pressure refrigerant sent from the outdoor heat exchanger 4 passes through the indoor second two-way valves V2b and V2c of the indoor units 6b+6c in the heating mode, and flows into the indoor heat exchangers 3b and 8c. Dissipates heat into the room (heating operation). After that, the indoor first expansion valve Vlb
, Vlc, and the header 20, the refrigerant that has been depressurized by the indoor second expansion valve EV2a of the indoor unit 6a in the cooling mode and becomes a liquid or two-phase state is transferred to the indoor heat exchanger 8a.
After heat is absorbed from the room (cooling operation), a direction valve V is installed in the indoor cylinder.
It returns to the outdoor expansion valve 5 in the outdoor unit 1 via la.

In this case, the outdoor heat exchanger 4 should cover the evaporation capacity obtained by subtracting the evaporation capacity of the indoor unit 6a, which is in cooling operation, from the evaporation capacity required for heating the indoor units (ib, 3c). Therefore, the capacity of the outdoor heat exchanger 4 is smaller than when all indoor units are in heating mode.
In particular, when the outside temperature is high, the rotation speed of the outdoor blower 9 is lowered to keep the heat dissipation capacity of the outdoor heat exchanger 4 low, thereby suppressing the heat absorption capacity of the outdoor heat exchanger 4 and lowering the evaporation temperature. By lowering the pressure, it is possible to suppress an extreme increase in the compressor discharge pressure, and the reliability of the pressure W+ machine is improved.

As mentioned above, the outdoor unit controls the outside temperature and the indoor unit's cooling, and
An outdoor heat exchanger whose capacity can be varied according to the operating capacity of the heating system is installed, a header is installed on the indoor unit, two two-way valves and expansion valves are installed on each indoor unit, and an outdoor heat exchanger is installed on the indoor unit. By controlling the two-way valve installed in the bypass circuit between the expansion valve and the ladder as described above, it is possible to realize simultaneous heating and cooling operations throughout the year.

In the above embodiment, the header 20 is connected to each indoor unit 6a, 6.
b, 6c have the same diameter specifications, but each indoor unit 6
The same effect can be obtained by installing dedicated headers for each of a, 6b, and 6c and connecting these headers with pipes of different diameters.

Effects of the Invention As described above, the present invention provides a variable capacity compressor, a four-way valve, an outdoor blower whose rotation speed can be varied according to the outside temperature and the operating capacity of indoor unit cooling and heating, and an outdoor heat exchanger. , and an outdoor unit consisting of an outdoor expansion valve.

Indoor 1111 Multiple indoor units consisting of a first two-way valve, an indoor heat exchanger, an indoor blower, an indoor second two-way valve, an indoor first expansion valve, and an indoor second expansion valve are connected in parallel. The outdoor unit and each indoor unit are connected by a first indoor two-way valve P and a second indoor two-way valve, and the first indoor two-way valve and the indoor The indoor first expansion valve is connected between the inner heat exchanger and between the indoor second two-way valve and the indoor heat exchanger.

A circuit is formed that connects each indoor unit with a common expansion valve and a second #2 expansion valve on the indoor side, and a bypass circuit is formed between the outdoor expansion valve and the ladder through a two-way valve. As a result, in a multi-room air conditioner, it is possible to simultaneously perform cooling operation and heating rj5 operation for each room throughout the year.

[Brief explanation of the drawing]

FIG. 1 is a diagram of a refrigeration system of a heat pump type air conditioner according to an embodiment of the present invention, and FIG. 2 is a diagram of a refrigeration system of a heat pump type air conditioner showing a conventional example. 1... Outdoor unit, 2... Variable capacity compressor, 3... Four-way valve, 4... Outdoor heat exchanger, 5... Outdoor expansion valve, 6a to 6c... Indoor unit , 8a to 8c... Indoor heat exchanger, 9... Outdoor blower, 10a to 10c...
Indoor side blower, Vla to Vlc...Indoor side first two-way valve, V2a to V2c---Indoor side second two-way valve, EVla''
EV1c=・Indoor side first expansion valve, EV 2 a -E
V 2C...Indoor side second expansion valve, 20...Header nv...Two-way valve.

Claims (1)

[Claims] An outdoor unit consisting of a variable capacity compressor, a four-way valve, an outdoor heat exchanger, an outdoor blower, and an outdoor expansion valve; an indoor first two-way valve; an indoor heat exchanger; an indoor blower; 2, a refrigeration cycle in which a circuit is formed by connecting a plurality of indoor units consisting of a two-way valve, a first indoor expansion valve, and a second indoor expansion valve in parallel; The rotation speed can be varied according to the cooling and heating operating capacity of the machine, and the outdoor unit and each indoor unit are connected by a first two-way valve on the indoor side and a second two-way valve on the indoor side, Between the indoor first two-way valve and the indoor heat exchanger and between the indoor second two-way valve and the indoor heat exchanger, the indoor first expansion valve, the header, and the indoor second expansion A multi-room air conditioner characterized by forming a circuit connected by a valve, and forming a bypass circuit via a two-way valve between the outdoor expansion valve and the header.