JPH0599526A - Multi-chamber type air conditioner - Google Patents

Abstract

PURPOSE:To provide a multi-chamber type air conditioner in which a cooling operation and a heating operation can be freely selected for every indoor device under a freezing cycle, an accumulation of refrigerant in an indoor heat exchanger of the stopped indoor device is prevented under a less-expensive specification and then a desired cooling or heating capability can always be assured. CONSTITUTION:A multi-chamber type air conditioner is provided with an indoor device operating state sensor 21 and an indoor device controlling means 22 for use in sensing whether an indoor device 6 performs a cooling operation and a heating operation or the indoor device 6 is stopped. The indoor device control means 22 fully closes an expansion valve 7 in respect to the indoor device 6 being stopped in reference to a result of sensing operation of the indoor device operating state sensor 21, closes either the first solenoid valve 12 or the second solenoid valve 13 connected to a high voltage side and opens either one of them connected to a low voltage side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-room air conditioner, and more particularly to a refrigerating cycle of a multi-room air conditioner in which cooling and heating can be freely selected for each indoor unit.

[0002]

2. Description of the Related Art Conventionally, various developments have already been made for a multi-room air conditioner having a plurality of indoor units, for example, Refrigeration, Vol. 61, No. 708 (1st 1986).
(October issue) P1038 to 1045.

The conventional multi-room air conditioner of the above-mentioned publication will be described below with reference to the drawings.

In FIG. 4, reference numeral 1 denotes an outdoor unit of a multi-room air conditioner, which includes a compressor 2, a four-way valve 3, an outdoor heat exchanger 4,
It comprises an outdoor expansion valve 5. An indoor unit 6 includes an indoor expansion valve 7 and an indoor heat exchanger 8.

The outdoor unit 1 and the indoor unit 6 are annularly connected by a liquid pipe 9 and a gas pipe 10 to form a refrigerant circuit 11. It should be noted that four indoor units 6 are connected in this conventional example, and the subscripts a, b, c, and d are added to distinguish them.

Next, the operation of the multi-room air conditioner having the above structure will be described. First, the case of only the cooling operation will be described. Here, the operating states of the indoor units 6 are the indoor units 6a, 6
b, 6c ... Cooling, indoor unit 6d ... Each indoor expansion valve 7a, 7b, 7c in the stopped and operating state is opened according to each indoor load, and the indoor expansion valve 7d in the stopped state is fully closed. .. The high-temperature high-pressure gas discharged from the compressor 2 is condensed and liquefied by the outdoor heat exchanger 4 via the four-way valve 3, and the outdoor expansion valve 5
Each of the indoor expansion valves 7a, 7b, 7 via a, 5b, 5c
After being decompressed at c, each of the indoor heat exchangers 8a, 8b, 8c is vaporized and vaporized, and then returned to the compressor 2 via the four-way valve 3 to perform the cooling operation.

Next, the case of only the heating operation will be described. Here, the operating states of the indoor units 6 are the indoor units 6a, 6
b, 6c ... Heating, indoor unit 6d ... Each indoor expansion valve 7a, 7b, 7c in the stopped and operating state is opened according to each indoor load, and the indoor expansion valve 7d in the stopped state is in a slightly opened state ( For example, the opening is 200 STEP). The high-temperature and high-pressure gas discharged from the compressor 2 is guided to the indoor heat exchangers 8a, 8b, 8c via the four-way valve 3, where it is condensed and liquefied to the indoor expansion valves 7a, 7b, 7c. Through the outdoor expansion valve 5a,
After being decompressed by 5b and 5c, entering the outdoor heat exchanger 4 and evaporating and evaporating, it returns to the compressor 2 through the four-way valve 3 to perform heating operation.

[0008]

However, in the above-mentioned structure, when the indoor unit of the stopped indoor unit (for example, the indoor unit 6d) is present during the heating operation, if the indoor expansion valve of the indoor unit of the stopped indoor unit is fully closed, the chamber of the indoor unit of the stopped indoor unit is closed. Refrigerant is accumulated in the inner heat exchanger, and the circulation amount of refrigerant flowing to the heating indoor unit decreases, leading to a decrease in heating capacity.Therefore, the indoor expansion valve of the stopped indoor unit is set to a slightly open state, and the refrigerant is stopped. I was trying not to collect in the exchanger. However, if the opening of the indoor expansion valve of the stopped indoor unit is too small, refrigerant accumulates in the indoor heat exchanger of the stopped indoor unit, and if the opening is too large, the thermostat can perform capacity control according to the load. There is a problem that it is difficult to set the opening such that there is no capacity (even if capacity is not needed).

The present invention has been made in view of the above-mentioned problems, and it is possible to prevent the refrigerant from accumulating in the indoor heat exchanger of the stopped indoor unit with an inexpensive specification and always ensure the capacity of each indoor unit. It is intended to provide a multi-room air conditioner capable of freely cooling and heating each indoor unit.

[0010]

In order to solve the above problems, the present invention provides an outdoor unit comprising a compressor, a four-way valve and an outdoor heat exchanger, and a plurality of indoor chambers comprising an expansion valve and an indoor heat exchanger. Machine is connected in parallel via a first connecting pipe and a second connecting pipe, and one of the indoor heat exchangers is connected to the first connecting pipe or the second connecting pipe and a first solenoid valve, respectively. ,
A switchable connection is made via a second solenoid valve, the other one of the indoor heat exchangers is connected to a third connection pipe via an expansion valve, and the third connection pipe is connected to a flow control device. Via either the first connection pipe or the second connection pipe, whichever is connected to the outdoor heat exchanger, while the indoor unit is in cooling and heating operation or is stopped. The indoor unit operating state detector for detecting whether or not the indoor unit control unit, the indoor unit control unit, the indoor unit is stopped based on the detection result of the indoor unit operating state detector, the expansion The valve is fully closed, and one of the first solenoid valve and the second solenoid valve that is connected to the high pressure side is closed and the one that is connected to the low pressure side is opened.

[0011]

With the above-described structure, the present invention prevents the refrigerant from accumulating in the indoor heat exchanger of the stopped indoor unit during heating and heating-main operation, and ensures a predetermined capacity of the indoor unit that is always in operation. That is.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. Incidentally, the same parts as those of the conventional one are designated by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 1, reference numeral 1 is an outdoor unit of a multi-room air conditioner, which includes a compressor 2, a four-way valve 3, an outdoor heat exchanger 4,
It consists of an outdoor controller 20. An indoor unit 6 includes an expansion valve 7, an indoor heat exchanger 8, a first electromagnetic valve 12, a second electromagnetic valve 13, and an indoor controller 19.

One of the indoor heat exchangers 8 communicates with a first connecting pipe 14 for connecting the outdoor unit 1 and the indoor unit 6 via a first electromagnetic valve 12 and a second electromagnetic valve 13 to the other. Second connection pipe 15 for connecting the outdoor unit 1 and the indoor unit 6
And one of the indoor heat exchangers 8 is switchably connected to the first connection pipe 14 or the second connection pipe 15 by opening and closing the first solenoid valve 12 and the second solenoid valve 13. ing.

The other side of the indoor heat exchanger 8 has an expansion valve 7
Is connected to the third connecting pipe 16 via
The connection pipe 16 is connected to the first connection pipe 14 via the flow control device 17.

FIG. 4 is a block diagram of a multi-room type air conditioner in one embodiment of the present invention, and FIG. 5 is a flow chart of expansion valve and solenoid valve control of a stopped indoor unit. The expansion valve and solenoid valve control of the stopped indoor unit will be described with reference to FIGS. 4 and 5. First, the remote controller 18 of the indoor unit 6 is turned on, and the compressor 2
Starts and the system is operated (step 1). Next, the indoor unit operating state detector 21 detects whether all the connected indoor units are operating and the operating state of the system (steps 2 and 3). Obtaining the above information, the expansion valve and solenoid valve control of the stopped indoor unit when the system is in the cooling or cooling-main operating state through the indoor unit control means 22 is in the heating or heating-main operating state as in step 4. The control of the expansion valve and solenoid valve of the stopped indoor unit is controlled as in step 5.

Next, the operation of the multi-room air conditioner having the above structure will be described. First, the case of only the cooling operation will be described. Here, the operating states of the indoor units 6 are the indoor units 6a, 6
b, 6c ... Cooling, indoor unit 6d ... Stop. The flow of the refrigerant in this case is represented by a solid arrow, and the open / closed state of each valve is as follows. That is, the first solenoid valves 12a, 12b, 12c
Is closed, the second solenoid valves 13a, 13b, 13c are open, the flow control device 17 is open, and the expansion valves 7a, 7b in operation are
7c is an opening degree according to each indoor load. The first solenoid valve 12d, the second solenoid valve 13d, and the expansion valve 7d in the stopped state are closed by the expansion valve and solenoid valve control of the stopped indoor unit,
Open and fully closed.

The high temperature and high pressure gas discharged from the compressor 2 is
It is condensed and liquefied in the outdoor heat exchanger 4 via the four-way valve 3, and is led to the third connection pipe 16 through the first connection pipe 14 and the flow rate control device 17. And expansion valves 7a, 7b, 7c
After being decompressed by, each indoor heat exchanger 8a, 8b, 8c is vaporized and vaporized respectively, and then returns to the compressor 2 via the second solenoid valve 13 and the four-way valve 3 to perform the cooling operation. Further, one of the indoor heat exchangers 8d of the indoor unit 6d in the stopped state is fully closed by the expansion valve 7d, and the other is closed by the first solenoid valve 12d, and the indoor heat exchanger 8d is Since the refrigerant does not flow in and the second solenoid valve 13d is opened, the refrigerant is drawn to the low pressure side, so that the refrigerant does not accumulate in the indoor heat exchanger 8d.

Next, the case of only the heating operation will be described. Here, the operating states of the indoor units 6 are the indoor units 6a, 6
b, 6c ... heating, indoor unit 6d ... stop. The flow of the refrigerant in this case is indicated by a dashed arrow, and the open / closed state of each valve is as follows. That is, the first solenoid valves 12a, 12b, 12c
Is closed, the second solenoid valves 13a, 13b, 13c are open, the flow control device 17 is open, and the expansion valves 7a, 7b, 7c have opening degrees according to the indoor loads. First solenoid valve 12 in a stopped state
The d, the second solenoid valve 13d, and the expansion valve 7d are opened, closed, and fully closed by controlling the expansion valve and the solenoid valve of the stopped indoor unit, respectively.

The high-temperature high-pressure gas discharged from the compressor 2 is
Second solenoid valves 13a, 13b, 13c via the four-way valve 3
Is guided to each indoor heat exchanger 8a, 8b, 8c via
Here, it is condensed and liquefied, flows into the third connecting pipe 16 through the expansion valves 7a, 7b, and 7c, is depressurized to a low-pressure two-phase state by the flow control device 17, and passes through the first connecting pipe 14 to the outside of the room. After entering the heat exchanger 4 and evaporating and evaporating, it returns to the compressor 2 via the four-way valve 3 to perform heating operation. Further, one of the indoor heat exchangers 8d of the indoor unit 6d in the stopped state is fully closed by the expansion valve 7d, and the other is opened by the second electromagnetic valve 13d, and the indoor heat exchanger 8d is Since the refrigerant does not flow in and the first solenoid valve 12d is opened, the refrigerant is drawn to the low pressure side, so that the refrigerant does not accumulate in the indoor heat exchanger 8d.

Next, the case of the cooling main operation will be described with reference to FIG. Here, the operating state of each indoor unit 6 is the indoor units 6a, 6b ... Cooling, the indoor unit 6c ... Heating, the indoor unit 6d ... Stop, and the open / close state of each valve is as follows. That is, the first
The solenoid valves 12a and 12b are closed, the first solenoid valve 12c is open, the second solenoid valves 13a and 13b are open, the second solenoid valve 13c is closed,
The flow rate control device 17 is open, and the expansion valves 7a, 7b, 7c have opening degrees according to the indoor loads. The first solenoid valve 12d, the second solenoid valve 13d, and the expansion valve 7d in the stopped state are closed, opened, and fully closed by controlling the expansion valve and the solenoid valve of the stopped indoor unit, respectively.

The high-temperature high-pressure gas discharged from the compressor 2 is
It is condensed and liquefied to some extent in the outdoor heat exchanger 4 through the four-way valve 3, passes through the first connecting pipe 14, and is partially guided to the indoor heat exchanger 8c through the first electromagnetic valve 12c. Here, it is condensed and liquefied and flows into the third connecting pipe 16 through the expansion valve 7c. In addition, the remaining refrigerant passes through the flow rate control device 17 to the third
Of the expansion valve 7c, the pressure is reduced by the expansion valves 7a and 7b, and the indoor heat exchangers 8a and 8b are respectively vaporized and vaporized, and then the second connection pipe 15 is connected. After that, it returns to the compressor 2 via the four-way valve 3. Further, one of the indoor heat exchangers 8d of the indoor unit 6d in the stopped state is fully closed by the expansion valve 7d, and the other is closed by the first solenoid valve 12d, and the indoor heat exchanger 8d is Since the refrigerant does not flow in and the second solenoid valve 13d is opened, the refrigerant is drawn to the low pressure side, so that the refrigerant does not accumulate in the indoor heat exchanger 8d.

Next, the case of heating-main operation will be described with reference to FIG. Here, the operating state of each indoor unit 6 is indoor unit 6a, 6b ... Heating, indoor unit 6c ... Cooling, indoor unit 6d ... Stop, and the open / closed state of each valve is as follows. That is, the first
The solenoid valves 12a and 12b are closed, the first solenoid valve 12c is open, the second solenoid valves 13a and 13b are open, the second solenoid valve 13c is closed,
The flow rate control device 17 is open, and the expansion valves 7a, 7b, 7c have opening degrees according to the indoor loads. The first solenoid valve 12d, the second solenoid valve 13d, and the expansion valve 7d in the stopped state are opened, closed, and fully closed by the expansion valve and solenoid valve control of the stopped indoor unit, respectively.

The high-temperature high-pressure gas discharged from the compressor 2 is
The four-way valve 3 is passed through the second connecting pipe 15 and the second electromagnetic valves 13a, 13b to the indoor heat exchangers 8a, 8b where they are condensed and liquefied to pass through the expansion valves 7a, 7b. Three
Flows into the connection pipe 16 of. Then, a part of the refrigerant is decompressed by the expansion valve 7c, evaporated and vaporized by the indoor heat exchanger 8c, and flows into the first connection pipe 14 through the first electromagnetic valve 12c. The remaining refrigerant is decompressed by the flow control device 17 and the first
Of the first electromagnetic valve 12c, the refrigerant merges with the refrigerant from the first solenoid valve 12c, evaporates and vaporizes in the outdoor heat exchanger 4, and returns to the compressor 2 via the four-way valve 3. In addition, the indoor unit 6 in the stopped state
One of the indoor heat exchangers 8d of d is fully closed by the expansion valve 7d, and the other is closed by the first solenoid valve 12d, so that the refrigerant does not flow into the indoor heat exchanger 8d, Since the solenoid valve 13d is opened, it is pulled to the low pressure side, so that the refrigerant does not accumulate in the indoor heat exchanger 8d.

As described above, during heating and heating-based operation,
In the indoor unit in the stopped state, the expansion valve is fully closed, and either the first solenoid valve or the second solenoid valve, whichever is connected to the high pressure side, is closed to allow the refrigerant to flow into the indoor heat exchanger. Instead, the first solenoid valve or the second solenoid valve, whichever is connected to the low-pressure side, is opened to pull it to the low-pressure side, so the refrigerant accumulates in the indoor heat exchanger of the stopped indoor unit. First, it is to ensure a predetermined capacity of the indoor unit that is always in the operating state.

[0026]

As is apparent from the above description, the present invention includes an outdoor unit including a compressor, a four-way valve and an outdoor heat exchanger, and a plurality of indoor units including an expansion valve and an indoor heat exchanger. The first and second connecting pipes are connected in parallel via a first connecting pipe and a second connecting pipe, and one of the indoor heat exchangers is connected to the first connecting pipe or the second connecting pipe, respectively, and a first solenoid valve and a second electromagnetic valve. It is switchably connected via an electromagnetic valve, the other one of the indoor heat exchangers is connected to a third connection pipe via an expansion valve, and the third connection pipe is further connected via a flow rate control device. The first
Which is connected to the outdoor heat exchanger, whichever is connected to the connection pipe or the second connection pipe, and which detects whether the indoor unit is in cooling and heating operation or is stopped. The indoor operation state detector and the indoor unit control means, the indoor unit control means, the indoor unit is stopped based on the detection result of the indoor unit operation state detector, the expansion valve fully closed One of the first solenoid valve and the second solenoid valve that is connected to the high pressure side is closed, and the one that is connected to the low pressure side is opened.

Therefore, the multi-room air conditioner of the present invention prevents the refrigerant from accumulating in the indoor side heat exchanger of the stopped indoor unit at a low cost during heating and heating-main operation, and reduces the refrigerant circulation amount. It is possible to prevent a decrease in the capacity of each indoor unit due to the above, to always ensure the capacity of each indoor unit, and to freely cool and heat each indoor unit. Further, only two pipes are required to connect the indoor unit and the outdoor unit, which is excellent in work efficiency.

[Brief description of drawings]

FIG. 1 is a refrigeration cycle diagram of a multi-room air conditioner according to an embodiment of the present invention.

FIG. 2 is a refrigeration cycle diagram showing a cooling-main operation state of the multi-room air conditioner of the same embodiment.

FIG. 3 is a refrigeration cycle diagram showing a heating-main operating state of the multi-room air conditioner of the same embodiment.

FIG. 4 is a block diagram of the multi-room air conditioner of the same embodiment.

FIG. 5 is a flow chart of expansion valve and solenoid valve control of a stopped indoor unit of the multi-room air conditioner of the same embodiment.

FIG. 6 is a refrigeration cycle diagram of a conventional multi-room air conditioner.

[Explanation of symbols]

 1 outdoor unit 2 compressor 3 four-way valve 4 outdoor heat exchanger 6 indoor unit 7 expansion valve 8 indoor heat exchanger 12 first solenoid valve 13 second solenoid valve 14 first connection pipe 15 second connection pipe 16 Third connection pipe 17 Flow control device 19 Indoor controller 20 Outdoor controller

Claims (1)

[Claims] 1. An outdoor unit including a compressor, a four-way valve, and an outdoor heat exchanger and a plurality of indoor units including an expansion valve and an indoor heat exchanger are provided with a first connecting pipe and a second connecting pipe. And one of the indoor heat exchangers is switchably connected to the first connection pipe or the second connection pipe via a first solenoid valve and a second solenoid valve, respectively. The other one of the indoor heat exchangers is connected to a third connection pipe via an expansion valve, and the third connection pipe is further connected to the first connection pipe or the second connection via a flow rate control device. An indoor unit operating state detector and an indoor unit control, which are connected to either one of the pipes connected to the outdoor heat exchanger and which detect whether the indoor unit is in cooling and heating operation or stopped. Means, the indoor unit control means, the indoor unit operating state detector With respect to the indoor unit that has stopped based on the detection result, the expansion valve is fully closed, and the first
A multi-chamber air conditioner characterized in that one of the solenoid valve and the second solenoid valve connected to the high pressure side is closed and the one connected to the low pressure side is opened.