JPH03211373A - Multi-room type air conditioner - Google Patents

Abstract

PURPOSE:To allow selecting cooling operation and heating operation at the same time by a method wherein a high pressure pipe of a refrigerant branch circuit is diverted into two ways, one branch is connected to a liquid pipe through a two-way valve which cut off the spouting gas, a liquid header and two-way valves provided on room units, and the other branch and a low pressure pipe are connected to a gas pipe through an auxiliary three-way valve. CONSTITUTION:When room units respectively perform cooling and heating operation at the same time, the high temperature, high pressure refrigerant gas delivered from a compressor 1 is led to room units in heating operation through a delivery side three- way valve 3, a high pressure pipe 12, and auxiliary three-way valve 10a - 10c, and condensed at room heat exchangers 14a - 14c, so that heating effect is produced. The condensed refrigerant liquid is led to room units in cooling operation through liquid pipes 16a - 16c, two-way valves 19 provided on the room units, and liquid header 7, reduced in pressure by a restriction devices 15a - 15c and evaporated at room heat exchangers 14a - 14c, so that cooling effect can be produced. The evaporated low pressure refrigerant gas is induced by the compressor 1 through gas pipes 17a - 17c, auxiliary three way-valves 10a - 10c, a low pressure pipe 13, and a suction side three- way valve 4. Thus, cooling and heating operation can be performed at the same time.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to a multi-room air conditioner that is composed of one outdoor unit and a plurality of indoor units and is capable of heating and cooling at the same time.

0. Prior Art FIG. 6 is a refrigerant circuit diagram of an example of a conventional multi-room air conditioner. The outdoor unit 23 is composed of a refrigerant circuit of an overcrowded heat pump type air conditioner, and includes liquid pipes 29 and gas pipes 30, a power director branch circuit 31, and a power pipe branch circuit 31 connected to a plurality of indoor units 24 (three in the example shown). The space pipe branch circuit 25 branches as many as the indoor units 24, and cooling operation or heating operation is determined by the switching position of the four-way valve 26. In other words, during cooling operation, the refrigerant flows as shown by the solid line, and the pressure! The high-temperature, high-pressure power refrigerant discharged from the machine 27 is condensed in the indoor heat exchanger and is supplied to each indoor unit 24 via the liquid pipe branch circuit 31. Furthermore, the air is depressurized by the indoor unit filtering device 32 and evaporated in the indoor heat exchanger 33, thereby providing a cooling effect.

During heating operation, the flow of the refrigerant circuit can be reversed by switching the four-way valve 26 in the direction indicated by the wire. The operation modes of a multi-room air conditioner in such a circuit configuration are limited to cooling operation mode and heating operation mode,
Each indoor unit can only be selected to run or stop in its respective operation mode.

Problems to be solved by the invention: The above conventional multi-room air conditioners cannot operate cooling and heating in different rooms at the same time. It cannot respond to different negative muscles.

In addition, separate air conditioners are required for rooms that require annual cooling, such as computer rooms and power distribution rooms, and living rooms that are heated and cooled.

The present invention has been made in consideration of the above circumstances, and aims to provide a multi-room air conditioner that can select cooling operation and heating operation at the same time.

Means for Solving the Two Problems The present invention has been made in view of the above points, and includes an outdoor unit consisting of a variable capacity compressor, an outdoor heat exchanger, a three-way valve on the discharge side, a three-way valve on the suction side, etc. High-pressure piping and low-pressure piping are installed between the electronic expansion valve for the outdoor heat exchanger, refrigerant branch circuit, etc., and a distribution control device installed indoors, and multiple indoor units consisting of the indoor heat exchanger and throttling device, etc. , in an air conditioner in which a liquid pipe and a gas pipe are respectively provided between the branch flow control device, the refrigerant branch circuit of the branch flow control device has high pressure piping branched into three directions, and one side is blocked from inflow of discharge gas. The two-way valve, liquid pipe header, and two-way valve provided for each indoor unit are connected to the return pipe in sequence, and the other and low-pressure pipes are connected to the gas pipe via the auxiliary three-way valve provided for each indoor unit. It is an object of the present invention to provide a multi-room air conditioner configured to be connected.

Depending on the switching position of the three-way valve on the discharge side, the refrigerant flowing through the high-pressure piping can be converted to liquid or high-pressure two-phase refrigerant when the outdoor heat exchanger is used as a condenser, or high-temperature and high-pressure when bypassing the outdoor heat exchanger. It becomes a gas refrigerant.

The three-way valve on the suction side is controlled so that when the refrigerant returned from the low-pressure pipe is a low-pressure gas refrigerant, the refrigerant returns directly to the compressor suction pipe, and when the refrigerant returns from the low-pressure two-phase refrigerant, the outdoor heat exchanger is used as the evaporator. The auxiliary three-way valve provided for each indoor unit connects the gas pipe and low-pressure pipe when the indoor unit performs cooling operation, and connects the gas pipe and high-pressure pipe when the indoor unit performs heating operation. controlled.

When the indoor unit performs cooling and heating at the same time, the high-temperature, high-pressure gas refrigerant discharged from the compressor is guided to the indoor unit that is heating via the discharge side three-way valve, high-pressure piping, and auxiliary three-way valve, and is transferred to the indoor heat exchanger. A heating effect is obtained by condensing it. The condensed (further condensed) refrigerant is led to the cooling indoor unit via liquid pipes, two-way valves installed for each indoor unit, liquid pipe headers, etc., is depressurized by a throttling device, and evaporated in an indoor heat exchanger. By doing so, you can obtain a cooling effect. The evaporated low-pressure gas refrigerant is sucked into the compressor through the gas pipe, sub-three-way valve, low-pressure pipe, and suction-side three-way valve in this order. By configuring the refrigerant circuit as described above, it is possible to perform cooling and heating at the same time.

When the heating load is small, the outdoor heat exchanger is used as a condenser by switching the three-way valve on the discharge side, and the high-pressure piping becomes a high-pressure two-phase refrigerant. Furthermore, when only cooling is required, all refrigerant is condensed in the outdoor heat exchanger, and the high-pressure piping becomes liquid refrigerant.Two-way valves are installed for each liquid pipe header and each indoor unit to cut off the inflow of discharge gas. , and are guided to the indoor unit through liquid pipes in sequence.

Whether the high-pressure piping uses high-pressure two-phase refrigerant or liquid refrigerant is controlled by the air volume of the outdoor blower.

When the cooling load is small, part of the liquid refrigerant is used, and when only heating is used, all the liquid refrigerant is depressurized by the electronic expansion valve for the outdoor heat exchanger in the distribution control device, and the low-pressure piping becomes a low-pressure two-phase refrigerant. The outdoor heat exchanger is used as an evaporator by switching the three-way valve.

Embodiment An embodiment of the present invention will be explained based on FIGS. 1 to 5. The variable capacity compressor 1, the outdoor heat exchanger 2, the accumulator 18, and the flow of discharge gas into the compressor suction piping will be described below. Two-way valve 19 to shut off, variable air volume blower 20, three-way discharge valve 3
and an outdoor unit 5 consisting of a three-way valve 4 on the suction side, an electronic expansion valve 6 for the outdoor heat exchanger, a liquid pipe header 7, a two-way valve 8 that blocks discharge gas from flowing into the liquid pipe header, and each indoor unit. Two-way valves 9a, 9b, 9c and sub three-way valves 10a, 1 provided in
A high pressure pipe 12 and a low pressure pipe 13 are provided between the flow control device 11 consisting of 0b and 10c, and indoor heat exchangers 14a, 14b, 14c and a throttle device 15.
a.

Three indoor units A and B consisting of 15b, 15c, etc.

C) and branch pipes 16a between the branch control device 11 and the
, 16b, i6c and gas pipe 17a.

17b and 17c are provided. The check valve 21 blocks the flow of the high-temperature, high-pressure gas refrigerant discharged to the high-pressure distribution v12 into the outdoor heat exchanger 2 depending on the switching position of the discharge-side three-way valve 3. The check valves 22a, 22b, and 22c bypass the throttling devices 15a, 15b, and 15c when the indoor units A, B, and C are heating.

Next, the operation of the above configuration will be explained. The following table shows the heating load of the indoor unit in each operation mode, the state of the refrigerant in the high-pressure distribution f12, the state of the refrigerant in the low-pressure pipe 13, and the state of change in the function of the outdoor heat exchanger 2, respectively. .

In FIG. 1, arrows indicate the flow of refrigerant during operation mode 1, that is, only cooling operation, and indoor units A, B, and C are all performing cooling operation.

The high-temperature, high-pressure gas refrigerant discharged from the compressor 1 is guided to the outdoor heat exchanger 2 by the switching position of the three-way valve 3 on the discharge side, condenses into liquid refrigerant, and then passes through the high-pressure pipe 12, the two-way valve 8, and the liquid pipe. Header 7, two-way valves 9a and 9b provided for each indoor unit
, 9c and the liquid pipes 16a, 16b, 16c successively to the indoor units A, B, C, and then to the throttle device 15a.

The pressure is reduced in 15b and 15c, and the indoor heat exchangers 14a and 14
It evaporates in steps b and 14c to obtain a cooling effect.

The evaporated low-pressure gas refrigerant is contained in gas pipes 17a and 17b.

17c, sub three-way valve 10a, 10b, 10c, low pressure piping 1
3, the three-way valve 4 on the suction side, and the accumulator 1 in order to be sucked into the compressor 1.

Fig. 2 shows the flow of refrigerant with arrows when operating mode 2, that is, cooling operation and heating operation are performed simultaneously and the heating load is small, indoor unit A is in heating operation, indoor unit B is in heating operation,
C-force 9-reifu driving is carried out. The high-temperature, high-pressure gas refrigerant discharged from the compressor 1 is guided to the outdoor heat exchanger 2 by the switching position of the discharge-side three-way valve 3, and a portion thereof is condensed to become high-pressure two-phase refrigerant. At this time, in order to keep the temperature of the air blown from the indoor unit performing heating high, the air volume of the outdoor blower 20 is adjusted to control the condensation pressure. The high-pressure two-phase refrigerant passes sequentially through the high-pressure piping 12, the auxiliary three-way valve 10a, and the gas pipe 17a to the indoor unit. It is condensed in the heat exchanger 14a and becomes a liquid refrigerant to obtain a heating effect, as well as check valves 22a, ? ? Z tube 16a
, two-way valve 9a, liquid pipe header 7, two-way valve 9b9C5) It is led to the indoor units B and C via the rear pipes 16b and 16c in order, and then the pressure is reduced by the expansion devices 15b and 15c, and the indoor heat exchanger 1
4b and 14c, it evaporates and becomes a low-pressure gas refrigerant to obtain a cooling effect. The low pressure gas refrigerant is sucked into the compressor 1 through the gas pipes 17b, 17c, the sub three-way valves 10b, 10c, the low pressure pipe 13, the suction side three-way valve 4, and the accumulator 1 in this order.

Figure 3 shows the flow of refrigerant using arrows in operation mode 3, that is, when cooling operation and heating operation are performed simultaneously and the difference between cooling load and heating load is small. C is performing heating operation, and indoor unit B is stopped. The high-temperature, high-pressure gas refrigerant discharged from the compressor 1 is guided to the high-pressure pipe by the switching position of the discharge-side three-way valve 3, and is further transferred to the heat exchanger 14c of the indoor unit C via the sub-three-way valve 10c and the gas pipe 17c. It condenses to become a liquid refrigerant and provides a heating effect, as well as a check valve 22c, a liquid pipe 16c, and a two-way valve 9c.
, the liquid pipe header 7, the two-way valve 9a, and the rear pipe 16a.
It evaporates in the indoor heat exchanger 14a and becomes a low-pressure gas refrigerant to obtain a cooling effect. The low-pressure gas refrigerant is sucked into the compressor 1 through the gas pipe 17a, the sub three-way valve 10a, the low-pressure pipe 13, the suction-side three-way valve 4, and the accumulator 18 in this order.

In operation mode 1 to operation mode 3 shown in FIGS. 1 to 3 above, the electronic expansion valve 6 for the outdoor heat exchanger is normally closed, but the degree of heating of the suction force cooling a becomes excessive. At this time, part of the liquid refrigerant is bypassed to the low-pressure piping to prevent the temperature of the compressor discharge gas from rising.

Fig. 4 shows the flow of refrigerant with arrows in operation mode 4, that is, when cooling operation and heating operation are performed at the same time and the cooling load is small.
B is performing heating operation. The high-temperature, high-pressure gas refrigerant discharged from the compressor 1 is guided to the high-pressure pipe by the switching position of the discharge-side three-way valve 3, and then to the indoor unit A via the sub-three-way valves 10a, 10b and the gas pipes 17a, 17b.

It is condensed in the heat exchangers 14a and 14b of B to become a liquid refrigerant to obtain a heating effect, and the check valve 22a.

22b,? (The liquid refrigerant is guided to the liquid pipe header 7 via the seven pipes 16a, 16b and the two-way valves 9a, 9b sequentially.
'c is depressurized and evaporated in the heat exchanger 14C to become a low-pressure gas refrigerant to obtain a cooling effect. A part of the liquid refrigerant is depressurized by the outdoor heat exchanger electronic expansion valve 6 and becomes a low-pressure two-phase refrigerant, which is mixed with the low-pressure gas refrigerant that returns via the gas pipe 17c and the sub three-way valve 10c, and is mixed with the low-pressure gas refrigerant that returns through the gas pipe 17c and the sub three-way valve 10c. It is led to the outdoor heat exchanger 2 through the suction side three-way valve 4, where it is evaporated, and then sucked into the compressor 1 through the two-way valve 19 and the accumulator 1.

In FIG. 5, arrows indicate the flow of refrigerant during operation mode 5, that is, only heating operation, and indoor units A, B, and C are all performing heating operation.

The high-temperature, high-pressure gas refrigerant discharged from the compressor 1 is guided to the high-pressure pipe 12 by the switching position of the three-way valve 3 on the discharge side, and then to the sub-three-way valves 10a, 10b, 10C, and the gas pipes 17a, 17b.
, 17c to the indoor rooms IA, B, and C, and then to the heat exchanger 14a.

14b, 14cT: Condenses to become a liquid refrigerant and provides a heating effect. Furthermore, check valves 22a, 22b, 22cS liquid pipe 16a
, 16b, 16c, two-way valve 9a.

9b, 9c and the liquid pipe header 7, the pressure is reduced by the outdoor heat exchanger electronic expansion valve 6, and it becomes a low-pressure two-phase refrigerant, which is evaporated in the outdoor heat exchanger via the low-pressure pipe 13 and the suction side three-way valve 4, Further, it is sucked into the compressor 1 through a two-way valve 19 and an accumulator.

The configuration and operation of the embodiment have been explained above, but indoor unit A
, B, and C do not necessarily have the same capacity, the selection of each operating mode and the operating capacity of the compressor 1 are determined in the following relationship. However, R1 and R2 represent constants determined experimentally.

Cooling load = Heating load = Operation mode 1 Σ (Indoor unit capacity during cooling operation) Σ (Indoor unit capacity during heating operation) When (Cooling load > 0) and (Heating load = 0) (Cooling load/ Heating load)〉R1 If R1≧(Cooling load/Heating load)≧ R2 (Cooling load/Heating load)〈R2 (Cooling load=0) and (Heating load>0) Operation mode 2 operation Mode 3 Operation mode 4 Operation mode 5 Compressor operation capacity = MAX (cooling load, heating negative head) / outdoor unit capacity (%) While maintaining the advantage of simplifying the indoor/outdoor connecting refrigerant piping of a room air conditioner, it is possible to operate zero room and heating at the same time in different rooms, making it possible to achieve optimal air conditioning for the different loads in each room. Furthermore, heat recovery operation in which one of the indoor heat exchangers is used as a condenser and the other as an evaporator has the effect of significantly saving energy.

In conventional heat pump air conditioners, the operation mode is switched by switching the four-way valve and performing reverse cycle operation, so when changing the operation mode, the effect of refrigerant in the indoor/outdoor connection piping on the operating status and compressor is reduced. is large. For example, when the defrost operation starts, the high-temperature, high-pressure gas refrigerant in the gas pipe returns to the compressor, posing the risk of an excessive rise in the temperature of the discharged gas. In contrast, the refrigerant circuit of the present invention
Because of the special structure, the flow of refrigerant in the indoor/outdoor connecting piping is unidirectional, with high-pressure piping from the outdoors to the indoors, and low-pressure piping from the indoors to the outdoors. However, the flow direction remains the same, and the influence of the refrigerant in the indoor/outdoor connecting piping on the operating conditions and compressor is minimized. This is particularly important in multi-room air conditioners that can perform heating and cooling at the same time, where the operating mode may frequently change each time the indoor unit is turned on or off due to the action of the room temperature thermostat, and contributes greatly to improving reliability. ing.

In operation mode 4 shown in Fig. 4, that is, when cooling operation and heating operation are performed simultaneously and the cooling load is small, the refrigerant circuit is configured so that the indoor heat exchanger and outdoor heat exchanger during cooling are connected in series. Since there is a pressure loss between these two exchangers, it is possible to omit an evaporation pressure regulating valve or the like to prevent freezing of the indoor heat exchanger.

[Brief explanation of drawings]

Figures 1 to 5 show the flow of refrigerant in each operating mode in the zero-control circuit of one embodiment of the present invention.
The figure is a refrigerant circuit diagram of an example of a conventional multi-room air conditioner. 1... Variable capacity compressor, 2... Outdoor heat exchanger, 3
...Discharge side three-way valve, 4...Suction side three-way valve, 5...
Outdoor unit, 6...Electronic expansion valve, 7...Liquid pipe header, 8
, 9.19... Two-way valve, 10... Sub-three-way valve, 11.
...Diversion control device, 12...High pressure piping, 13...-Low pressure piping, 14...Indoor heat exchanger, 15...Frame device, 16...? ! Pipe, 17...Gas pipe, 1st...Accumulator, 20...Variable air volume blower, 21.22...Reverse valve, A, B, C...Indoor unit procedure correction M (method ) April 25, 1990, Fumitake Yoshida, Director General of Jikogo Agency, 1, Indication of the case, Patent Application No. 2-69b9, 2, Name of the invention, Multi-room air conditioner 3, Person making the amendment, Relationship with the case Patent applicant name Toyo Career Kogyo Co., Ltd. 4 Agent address 752-ku Marunouchi Pildink 5, 2-4-1 Marunouchi, Chiyoda-ku, Tokyo 100 Date of procedural amendment order March 29, 1990 (Shipping date: Heisei) (April 24, 2016) 6゜ Amendment subject specification

Claims (1)

[Claims] An outdoor unit consisting of a variable capacity compressor, an outdoor heat exchanger, a three-way valve on the discharge side, a three-way valve on the suction side, etc., and a shunt control device installed indoors consisting of an electronic expansion valve for the outdoor heat exchanger, a refrigerant branch circuit, etc. In an air conditioner in which a high pressure pipe and a low pressure pipe are provided between the air conditioner and a liquid pipe and a gas pipe are respectively provided between a plurality of indoor units including an indoor heat exchanger, a throttle device, etc. and the branch control device, The refrigerant branch circuit of the branch control device is configured by branching the high-pressure pipe into two directions, and sequentially passing through a two-way valve that blocks the inflow of discharge gas on one side, a liquid pipe header, and a two-way valve provided for each indoor unit. A multi-room air conditioner characterized in that it is connected to a liquid pipe and the other and low pressure pipes are connected to a gas pipe via a sub three-way valve provided for each indoor unit.