JPS6145145B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a multi-chamber air conditioner, specifically a compressor,
This relates to a multi-room air conditioner consisting of an outdoor unit equipped with an outdoor heat exchanger connected to multiple indoor units equipped with an indoor heat exchanger and a cooling expansion mechanism. When at least one indoor unit among multiple indoor units is in cooling operation, at least one remaining indoor unit is enabled for heating operation, and all or a predetermined number of indoor units are placed in heating operation or cooling operation. The object of the present invention is to provide a multi-room air conditioner that can be operated.

Generally speaking, in this type of multi-room air conditioner, if even one of the multiple indoor units is in cooling operation,
The remaining indoor units can only perform cooling operation, and in the case of a heat pump type, if even one unit performs heating operation, the remaining indoor units can only perform heating operation, and one or more indoor units can only perform cooling operation. It was not possible to perform heating operation with the remaining indoor units when the unit was in use, or to perform cooling operation in the opposite case.

Therefore, when there are rooms that require heating at the same time as well as cooling, such as during the spring or autumn seasons or in buildings with many rooms, the heating operation is performed in parallel with the cooling operation in the rooms that require cooling. It was not possible to perform the heating operation in the required room at the same time.

However, in order to solve this problem, it is possible to use two compressors or two outdoor units, but since two compressors or outdoor units are required, there is a problem of high initial cost. I couldn't come up with a fundamental solution.

The present invention was invented to solve the above problems, and focuses on the fact that high-pressure gas refrigerant flows through the pipes from the compressor to the outdoor heat exchanger during cooling operation, and connects the pipes to each indoor unit. By providing a plurality of communicating branch pipes, when at least one of the indoor units is in a cooling operation, at least one of the remaining indoor units can be operated in a heating operation with the high pressure gas refrigerant, and all the indoor units can be heated. The number or all of a predetermined number of units can be operated in heating or cooling mode.

That is, the present invention solves the above-mentioned problems with a simple configuration, and the outdoor unit equipped with a compressor and an outdoor heat exchanger has a plurality of liquid-side branch pipes and a plurality of gas-side main pipes for each of the liquid-side main pipe and the gas-side main pipe. By providing a lateral branch pipe,
In addition to installing on-off valves in each of these branch pipes,
In a multi-room air conditioner in which a plurality of indoor units each equipped with an indoor heat exchanger and a cooling expansion mechanism are connected to these branch pipes, a heating expansion mechanism is interposed in the liquid side main pipe, and a heating expansion mechanism is interposed in the liquid side main pipe. , high pressure gas is flowed from the compressor to the gas side branch pipe, and low pressure gas is returned to the compressor from the outdoor heat exchanger to perform heating operation; and from the compressor to the outdoor heat exchanger. An air conditioning/heating switching means is provided that allows high pressure gas to flow and low pressure gas is returned from the gas side branch pipe to the compressor to enable cooling operation, while a plurality of branch pipes are provided in the pipe line through which high pressure gas flows during cooling operation. connecting each of these branch pipes to each gas side branch pipe between the on-off valve of the gas side branch pipe and each of the indoor heat exchangers, interposing an on-off valve in each of these branch pipes, and Allowing only flow from each liquid-side branch pipe to the liquid-side main pipe between the cooling expansion mechanism of each indoor unit and the on-off valve of each liquid-side branch pipe, and from the liquid-side branch pipe to the liquid-side main pipe. A connecting pipe with a check valve is installed to enable all of the indoor units to operate in a cooling or heating mode, and when at least one of the indoor units is in a cooling mode, at least one remaining indoor unit is installed. It is characterized by being capable of heating operation.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to an air conditioner in which three indoor units are connected to one outdoor unit will be described in detail below with reference to the drawings.

In the figure, 0 is the outdoor unit, A, B, and C are the indoor units;
is connected to the outdoor unit 0 via connecting pipes D and D.

The outdoor unit 0 is equipped with a compressor 1, an outdoor heat exchanger 2, a heating expansion mechanism 3, a liquid receiver 6, and an accumulator 7, and each of these devices is connected to a refrigerant pipe 8.
They are connected by each. Three liquid side branch pipes 10, 11, 12 are connected to the liquid side main pipe 9 of the refrigerant pipe 8 via headers, and on-off valves are provided to each of these liquid side branch pipes 10, 11, 12, respectively.
SVLA, SVLB, SVLC are interposed, and three gas side branch pipes 14, 15, 16 are connected to the gas side main pipe 13 of the refrigerant pipe 8 via a header,
Opening/closing valves SVGA, SVGB, and SVGC are interposed in each of these gas side branch pipes 14, 15, and 16, respectively. The on-off valves SVLA..., SVGA use, for example, two-way solenoid valves.

The six on-off valves mentioned above SVLA..., SVGA...
All of these are so-called one-way type, that is, the refrigerant flows in a fixed direction by opening operation, more specifically, the opening/closing valve
SVGA... allows flow only from the gas side branch pipe 14... to the gas side main pipe 13 direction, and the on-off valve SVLA... allows flow only from the liquid side main pipe 9 to the liquid side branch pipe 10... direction,
The closing action prevents the flow from flowing in a direction opposite to this fixed direction.

Note that 17 is an outdoor fan, 17a is an outdoor fan motor, and 18 is a high pressure control valve.

The indoor units A, B, and C each have an indoor heat exchanger 19 and an expansion mechanism 2 for cooling.
0, a check valve 22 is provided in a bypass circuit 21 that bypasses the expansion mechanism 20 during heating, and these devices are connected by refrigerant pipes 23, respectively. The liquid side pipes and gas side pipes in the refrigerant pipes 23 of these indoor units A, B, and C are connected to the liquid side branch pipes 10, 11, and 11 of the outdoor unit 0, respectively.
12 and gas side branch pipes 14, 15, and 16 via connecting pipes D and D, respectively.

Note that 24 is an indoor fan, and 24a is an indoor fan motor.

And each opening/closing valve SVLA..., SVGA during cooling
...Indoor unit A that requests cooling operation,
The compressor 1 is driven with only those connected to B and C open, and the high-pressure gas refrigerant discharged from the compressor 1 is condensed and liquefied in the outdoor heat exchanger 2 and sent to the operating indoor unit. It flows only to A, B, and C, and after cooling the room that requires cooling operation due to the evaporation action in the indoor heat exchanger 19, the compressor 1 is turned on again.
The cycle of returning to is repeated.

However, in the multi-chamber air conditioner constructed as described above, the compressor 1 shown in FIG.
high-pressure gas is flowed from the gas side branch pipes 14, 15, and 16, and low-pressure gas is returned from the outdoor heat exchanger 2 to the compressor 1 for heating operation. High pressure gas flows through the heat exchanger 2, and the gas side branch pipes 14, 15, 16
Cooling/heating switching means SV ₁ , SV ₂ , 35 are provided for returning low pressure gas from the compressor 1 to the compressor 1 to enable cooling operation, and a branch pipe is provided in the pipe 8 a through which high pressure gas flows during cooling operation in the refrigerant pipe 8 . Connect 37,
Three branch pipes 25, 26, and 27 are connected to this branch pipe 37 via headers. These branch pipes 25, 26, 27 are connected to the gas side branch pipes 14, 1
connected to each gas side branch pipe 14, 15, 16 between the on-off valves 5, 16, SVGA, SVGB, SVGC and each of the indoor heat exchangers 19, 19, 19,
On-off valves in each of these branch pipes 25, 26, 27
Interpose SVA, SVB, and SVC respectively.

And each expansion mechanism 20, 20, 20 of each indoor unit A, B, C and liquid side on-off valve SVLA,
Connection pipes 28, 29, 30 are connected from the liquid pipe line between SVLB and SVLC to the liquid side main pipe 9, and the liquid side branch pipes 11, 12 are connected to these communication pipes 28, 29, 30 in the direction of the liquid side main pipe 9. A check valve 31 is installed to allow only the flow of water.

On-off valves installed in the branch pipes 25, 26, 27
SVA, SVB, and SVC are for each indoor unit A, B,
When all of the indoor units A, B, and C are in the cooling operation or stopped state and do not request heating, they are in the closed state, and at least one of each indoor unit A, B, and C is in the cooling operation, and at least one of the remaining units is in the closed state. When heating is requested, and when all units or a predetermined number of units are requesting heating, only those connected to the outdoor unit are kept open. At this time, the on-off valves installed in the liquid side branch pipes 10, 11, 12 and the gas side branch pipes 14, 15, 16 communicating with the indoor unit requesting heating are maintained in a closed operating state.

In addition, communication pipes 32 are provided between the connection pipe D side positions of the on-off valves SVLA, SVLB, and SVLC in the liquid side branch pipes 10, 11, and 12 and between the outdoor heat exchanger 2 and the liquid receiver 6, respectively. A check valve 33 and a capillary reach tube 34 are installed in each communication pipe 32 to prevent liquid refrigerant leaking from the shut-off valves SVA, SVB, and SVC from accumulating in indoor units A, B, and C while the unit is stopped. In order to return the liquid refrigerant to the outlet side of the outdoor heat exchanger 2, the indoor units A, B,
Liquid refrigerant is prevented from accumulating in C.

The operation of the air conditioner configured as above will now be explained.

Among the three indoor units A, B, and C, one indoor unit A is in cooling operation, that is, the on-off valves installed in the branch pipes 25, 26, and 27.
Shut off SVA, SVB, and SVC, and open/close valves SVLA and
At the same time as opening the SVGA, the compressor 1 is driven, and the refrigerant condensed in the outdoor heat exchanger 2 is transferred to the indoor unit A.
In order to perform heating operation on one indoor unit B of the remaining indoor units B and C in a state where only the remaining indoor units B and C are electrically connected, the on-off valve SVB installed in the branch pipe 26 is opened.

That is, a portion of the gas discharged from the compressor 1 flows into the indoor unit B through the branch pipe 37, the branch pipe 26, and the on-off valve SVB, and is condensed in the indoor heat exchanger 19 to produce a heating effect. The condensed liquid refrigerant passes through the check valve 22 to the connecting pipe D and the liquid side branch pipe 1.
1, it flows into the liquid side main pipe 9 through the communication pipe 29 and the check valve 31, and joins the high-pressure liquid refrigerant flowing from the liquid receiver 6 side to cool the indoor unit A. This high-pressure liquid refrigerant is transferred to the liquid side branch pipe 10 and the on-off valve
SVLA, flows into the indoor unit A through the connecting pipe D, evaporates in the indoor heat exchanger 19, performs a cooling action, and is connected to the gas side branch pipe 14, the on-off valve SVGA, and the gas side main pipe 1.
3 and then returned to the compressor 1, and the cycle is repeated.

Next, when only indoor unit A is in cooling operation, in order to operate both remaining indoor units B and C in heating operation, an on-off valve installed in branch pipes 26 and 27 is required.
SVB and SVC are opened, and by this operation, part of the gas discharged from the compressor 1 is transferred to the branch pipe 26,
The air flows into indoor units B and C from 27 and is condensed in indoor heat exchangers 19 and 19, respectively, and performs a heating effect. The condensed liquid refrigerant is transferred to the connecting pipe 2.
9, 30 and check valves 31, 31, it flows into the liquid side main pipe 9, and joins with the high pressure liquid refrigerant flowing from the liquid receiver 6 side. After that, the high pressure liquid refrigerant is transferred to the liquid side branch pipe 1.
0, the gas side branch pipe 14 after flowing through the on-off valve SVLA and the connecting pipe D and performing cooling action in the indoor unit A;
It flows through the on-off valve SVGA and the gas side main pipe 13 and is returned to the compressor 1.

Also, the above explanation assumes that only one indoor unit A is in cooling operation, but indoor units A and B
In order to operate one of the remaining indoor units C for heating while two units are in cooling operation, branch pipe 27
This operation opens the on-off valve SVC installed in the branch pipe 27.
The refrigerant then flows into the indoor unit C to perform a heating effect, and then flows into the liquid side main pipe 9 from the communication pipe 30, where it joins with the refrigerant flowing from the liquid receiver 6 side and flows into the indoor units A and B. The two streams are divided, each having a cooling effect, and then returned to the compressor 1.

However, the above explanation is based on indoor units A, B,
When at least one unit of C is in cooling operation, at least one remaining unit is in heating operation.
As shown by the broken line in the figure, a heating expansion mechanism 3 is provided in the liquid side main pipe 9 between the outdoor heat exchanger 2 and the liquid receiver 6, and a check valve 5 is provided in the bypass circuit 4 of the expansion mechanism 3. On the other hand, a first on-off valve is provided between a branch point toward the branch pipes 25, 26, and 27 side in the pipe line 8a through which high-pressure gas flows during cooling and the outdoor heat exchanger 2.
SV ₁ , and a communication pipe 3 between the outdoor heat exchanger 2 side of the first on-off valve SV ₁ and the gas side main pipe 13.
By providing the second on-off valve _SV2 in the connecting pipe 35, all or a predetermined number of indoor units A, B, and C can be operated for heating or cooling. For convenience of explanation, the above heating operation will be referred to as heating-main operation, and the above-described cooling operation will be referred to as cooling-main operation. In addition, for cooling-based operation, the first on-off valve SV ₁ is opened and the second on-off valve SV ₁ is closed, and for heating-based operation, the first on-off valve SV 1 is closed.
SV ₁ is closed and the second on-off valve SV ₂ is used.

The heating-based operation will be explained below. In this heating-based operation, as described above, the first on-off valve SV ₁ is closed, the second on-off valve SV ₂ is opened, and the branch pipes 25, 26,
Open the on-off valves SVA, SVB, and SVC installed in 27 that communicate with the indoor unit that requests heating, and open the gas side branch pipes 14, 15, and 16 and the liquid side branch pipe 1.
Each on-off valve SVGA installed at 0, 11, 12...
This is done by closing each SVLA...

By doing so, the discharged gas is transferred to the branch pipes 25, 2.
The liquid flows into the indoor unit requesting heating through only those connected to the indoor units requesting indoor heating at 6 and 27, and releases the condensation heat in the indoor heat exchanger 19 to perform a heating effect. Lateral canal 10,1
1, 12, and the communication pipes 28, 29, and 30, which flow into the liquid-side main pipe 9 through those communicating with the indoor unit requesting heating, and then the expansion mechanism 3 and the outdoor heat exchanger 2.
The cycle of returning the air to the compressor 1 through the communication pipe 35 is repeated.

When the heating-main operation is being performed as described above, at least one of the indoor units A, B, and C is
To operate the unit for cooling, open/close valves SVA, SVB,
Only the SVC connected to the indoor unit requesting internal heating is opened, and the on-off valve SVGA...
..., SVLA..., only those that communicate with the indoor unit requesting cooling are placed in the open operating state.

That is, taking as an example a case where one of the indoor units A is operated for heating and the remaining indoor units B and C are operated for cooling, the on-off valve SVA connected to the indoor unit A of the on-off valve SVA...... At the same time, only the on-off valves SVGC and SVLC that communicate with the inner indoor unit C of the on-off valves SVGA, SVLA, and so on are opened. At this time, the discharged gas flows into the indoor unit A through the branch pipe 25, releases condensation heat in the indoor heat exchanger 19, and performs a heating effect. While repeating the cycle of returning the refrigerant to the compressor 1 through the outdoor heat exchanger 2 and the communication pipe 35, the refrigerant that has flowed from the communication pipe 28 into the liquid side main pipe 9 from the header passes through the liquid side branch pipe 12. It flows into the indoor unit C, evaporates in the indoor heat exchanger 19, performs a cooling effect, and then returns to the compressor 1 through the gas side branch pipe 16 and the gas side main pipe 13, repeating the cycle.

In particular, when outdoor unit A is in heating operation, indoor unit B is in cooling operation, and indoor unit C is stopped in cooling operation and heating operation, both the first and second on-off valves SV ₁ and SV ₂ should be closed. Therefore, unnecessary heat radiation or heat absorption in the outdoor heat exchanger 2 can be completely eliminated, and when operating with only one of the first and second on-off valves SV ₁ and SV ₂ open as described above, In comparison, it is possible to perform cooling operation and heating operation at the same time efficiently.

By using the first and second on-off valves SV ₁ and SV ₂ in this way, each room can be cooled at will, regardless of whether the indoor units in other rooms are in cooling or heating mode. Alternatively, heating operation can be performed.

In the above explanation, the on-off valves SVLA installed in the liquid side branch pipes 10 are all one-way type, but they are variable type, that is, the refrigerant can flow in either the forward or reverse direction. If a device that can control the flow cutoff is used, the connecting pipes 28, 2 equipped with check valves 31, 31, 31 as shown in FIG.
9 and 30 become unnecessary.

In addition, the above explanation is for an air-conditioning/heating switching means to enable air-conditioning or heating-based operation.
First and second on-off valves SV ₁ and SV ₂ and communication pipe 35
However, as shown in FIG. 2, a four-way switching valve 36 is used as the heating/cooling switching means,
The branch pipe 2 is connected to the refrigerant pipe 8 between the inflow side of the outdoor heat exchanger 2 and the boat through which high pressure gas flows out during cooling.
It is also possible to connect 5, 26, and 27. In addition, in Figure 2, the on-off valve SVA...
..., SVGA... are reversible types, and the on-off valves SVLA... are unidirectional types.

That is, when the three indoor units A, B, and C are operated mainly for cooling and for heating, the four-way switching valve 36 is switched so that the refrigerant flows in the direction of the solid arrow in FIG. 2, and the on-off valves SVGA...SVLA... Among the valves SVA, only those communicating with the indoor unit requesting cooling are opened, and among the on-off valves SVA, only those communicating with the indoor unit requesting heating are opened.

Also, when the three indoor units A, B, and C are operated mainly for heating and for cooling, the four-way switching valve 36 is switched so that the refrigerant flows in the direction of the broken line arrow in Figure 2, and the on-off valve SVGA... Open only those connected to indoor units requesting heating, and open/close valves.
Of the SVLA and SVA, only the one that communicates with the indoor unit requesting cooling is opened.

However, the operation of the air conditioner mainly for cooling or heating in Fig. 2 is due to the operation of the first and second on-off valves.
Since this is basically the same as the case shown in FIG. 1 using SV ₁ and SV ₂ , no particular details will be given.

In the above explanation, the number of indoor units is 3, but even if there are 2 or 4 or more, 3 indoor units will be used.
Needless to say, the same effect as in the case of a stand is produced.

As described above, the present invention provides a multi-room air conditioner in which a plurality of liquid side branch pipes and a plurality of gas side branch pipes in an outdoor unit are each provided with on-off valves, and a plurality of indoor units are connected between these branch pipes. A heating expansion mechanism 3 is interposed in the liquid side main pipe 9, and
High-pressure gas flows from the compressor 1 to the gas side branch pipes 14, and low-pressure gas is returned from the outdoor heat exchanger 2 to the compressor 1 for heating operation. Air conditioning/heating switching means SV ₁ , SV ₂ , 35 or 36 that allows high pressure gas to flow through the outdoor heat exchanger 2 and returns low pressure gas to the compressor 1 from the gas side branch pipes 14 . . . to enable cooling operation. At the same time, a plurality of branch pipes 25... are connected to the pipe line 8a through which high-pressure gas flows during cooling operation, and each of these branch pipes 25... is connected to the gas side branch pipe 14...
on-off valve SVGA... and each of the indoor heat exchangers 19
and each of the branch pipes 25... is connected to each gas side branch pipe between them, and an on-off valve SVA... is interposed in each of these branch pipes 25..., and the cooling expansion mechanism 20 of each indoor unit A... and each of the liquids are connected to A check valve 31 that only allows flow from the liquid side branch pipe to the liquid side main pipe 9 is provided from each liquid side branch between the on-off valve SVLA of the side branch pipe 10 and the liquid side main pipe 9 side. Since the connecting pipe 28... is installed, when at least one of the plurality of indoor units is in cooling operation, at least one remaining indoor unit can be operated in heating mode at the same time. It is. Therefore, this multi-room air conditioner is suitable for use when cooling and heating are required at the same time, such as during the middle of the year. Moreover, when at least one indoor unit among the plurality of indoor units A is in cooling operation, not only can at least one remaining indoor unit be in heating operation at the same time, but also the heating expansion mechanism 3 Air conditioning/heating switching means
Since SV ₁ , SV ₂ , 35 or 36 are provided, all indoor units, for example, if three indoor units A, B, and C are connected to one outdoor unit 0, all three units will be heated. It can be operated in full operation or in full cooling operation.

[Brief explanation of the drawing]

FIG. 1 is a refrigerant piping system diagram showing an embodiment of the present invention, and FIG. 2 is a refrigerant piping system diagram showing another embodiment of the invention. 14, 15, 16... Gas side branch pipe, 19... Indoor heat exchanger, 25, 26, 27... Branch pipe,
SVGA, SVGB, SVGC...on/off valve, SVLA,
SVLB, SVLC...Open/close valve, SVA, SVB, SVC...
...Opening/closing valve, A, B, C... Indoor unit, 1...
Compressor, 2...Outdoor heat exchanger, 3...Heating expansion mechanism, O...Outdoor unit, 9...Liquid side main pipe,
13... Gas side main pipe, 10, 11, 12... Liquid side branch pipe, 20... Cooling expansion mechanism, SV ₁ , SV ₂ , 3
5, 36... Air conditioning/heating switching means, 28, 29, 30
...Connection pipe.

Claims (1)

[Claims] 1 A plurality of liquid side branch pipes 10 and gas side branch pipes 14 are installed in the liquid side main pipe 9 and the gas side main pipe 13 of the outdoor unit 0 equipped with the compressor 1 and the outdoor heat exchanger 2, respectively.
. . . and these branch pipes 10 and 14 are provided.
... respectively on-off valves SVLA and SVGA...
..., and a plurality of outdoor units A each equipped with an indoor heat exchanger 19 and a cooling expansion mechanism 20 are connected to these branch pipes 10 and 14... It is an air conditioner,
The heating expansion mechanism 3 is interposed in the liquid side main pipe 9, and the gas side branch pipe 14 is connected from the compressor 1 to the gas side branch pipe 14...
high pressure gas is caused to flow through the outdoor heat exchanger 2.
low pressure gas is returned to the compressor 1 from the compressor 1 for heating operation, high pressure gas is flowed from the compressor 1 to the outdoor heat exchanger 2, and the gas side branch pipe 14
Air conditioning/heating switching means SV ₁ , SV ₂ , 35 for returning low pressure gas from . . . to the compressor 1 to enable cooling operation.
or 36, a plurality of branch pipes 25... are connected to the pipe line 8a through which high-pressure gas flows during cooling operation, and each of these branch pipes 25... is connected to the gas side branch pipe 1.
The on-off valves SVGA and the indoor heat exchanger 19 are respectively connected to the gas side branch pipes of 4..., and the on-off valves SVA are interposed in these branch pipes 25, respectively, and Each indoor unit A...
The cooling expansion mechanism 20 and each of the liquid side branch pipes 10...
A communication pipe 28 having a check valve 31 that allows flow only from the liquid side branch pipe to the liquid side main pipe 9 from each liquid side branch pipe to the liquid side main pipe 9 between the on-off valve SVLA... ......, the indoor unit A...
A multi-room air conditioner characterized in that all of the outdoor units are capable of cooling operation or heating operation, and when at least one of the outdoor units is operating cooling operation, at least one of the remaining outdoor units is capable of heating operation. Machine.