JPH06249542A - Air conditioner - Google Patents

Abstract

PURPOSE:To demonstrate an adequate cooling capacity by providing a flow control means on an indoor side of a discharge pipe, which regulates a flow rate of a refrigerant in response to a number of ones in a thermo-off condition among indoor units in a heating operation when cooling and heating operations are simultaneously effected. CONSTITUTION:An indoor side discharge pipe 10R is provided with a flow control valve 15. The flow control valve 15 regulates a flow rate of a refrigerant in response to a number of ones in a thermo-off condition among indoor units in a heating operation when cooling and heating operations are simultaneously effected. When all of the indoor units B and C in a heating operation are rendered thermo-off, the flow control valve 15 is fully closed. When only one of the indoor units B and C in a heating operation is rendered thermo-off, the flow control valve 15 is made small in opening degree. Therefore, a refrigerant flowing into the indoor unit A in a cooling operation is rendered rich in a liquid content, so that the indoor unit A can demonstrate an adequate cooling capacity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner having a plurality of indoor units and capable of cooling operation, heating operation and simultaneous cooling / heating operation.

[0002]

2. Description of the Related Art One example of a conventional air conditioner of this type is shown in FIG. In FIG. 3, 1 is a compressor, and 10 is a discharge pipe, which is connected to the discharge side of the compressor 1. A suction pipe 11 is connected to the suction side of the compressor 1. 3 is an outdoor heat exchanger, the gas side of which is a discharge pipe through an outdoor switching valve 2.
10 or the suction pipe 11 is selectively connected. 7A, 7B, 7C are indoor heat exchangers, and their gas sides are indoor switching valves 8
It is selectively connected to the discharge pipe 10 or the suction pipe 11 via A, 8B, and 8C. An outdoor throttling mechanism 4 is arranged on the liquid side of the outdoor heat exchanger 3. Reference numerals 6A, 6B, and 6C denote indoor throttle mechanisms, which are provided on the liquid sides of the indoor heat exchangers 7A, 7B, and 7C, respectively. A liquid refrigerant pipe 12 connects the liquid side of the outdoor side expansion mechanism 4 and the liquid side of the plurality of indoor side expansion mechanisms 6A, 6B, 6C. Reference numeral 13 is an outdoor blower, which allows the indoor heat exchanger 3 to pass outside air. 9A, 9B and 9C are indoor blowers, and indoor air is passed through the indoor heat exchangers 7A, 7B and 7C. A receiver 5 is provided in the liquid refrigerant pipe 12. An accumulator 14 is provided on the suction side of the compressor 1.

Reference numeral O denotes an outdoor unit, in which a compressor 1, an outdoor switching valve 2, an outdoor heat exchanger 3, an outdoor blower are provided.
13, outdoor side diaphragm mechanism 4, receiver 5, accumulator 14
And so on. A, B, and C are indoor units. The indoor unit A includes an indoor heat exchanger 7A, an indoor switching valve 8A, an indoor throttle mechanism 6A, and an indoor blower 9A, and an indoor unit B has an indoor side. The heat exchanger 7B, the indoor switching valve 8B, the indoor throttle mechanism 6B and the indoor blower 9B are incorporated, and the indoor unit C has an indoor heat exchanger 7C, an indoor switching valve 8C, an indoor throttle mechanism 6C and a room. Inner blower 9C is built in. The plurality of indoor units A, B and C are connected in parallel to the outdoor unit O via a discharge pipe 10, a suction pipe 11 and a liquid refrigerant pipe 12.

When all or a part of the indoor units A, B, C are cooled, for example, when the indoor units A, B are cooled and the indoor unit C is stopped, the outdoor throttle mechanism 4 is It is fully opened, the indoor throttle mechanisms 6A and 6B are set to predetermined openings, and the indoor throttle mechanism 6C is fully closed. The outdoor switching valve 2 is switched so that the outdoor heat exchanger 3 communicates with the discharge pipe 10, and the indoor switching valve 8
A and 8B are switched so that the indoor heat exchangers 7A and 7B communicate with the suction pipe 11. Then, the refrigerant gas compressed by the compressor 1 enters the outdoor heat exchanger 3 through the outdoor discharge pipe 10L and the outdoor switching valve 2 and radiates heat to the outside air blown by the outdoor blower 13 there. It is condensed and liquefied to become a liquid refrigerant. Next, this liquid refrigerant passes through the fully opened outdoor side expansion mechanism 4 and enters the receiver 5, where the gas components are separated. The liquid refrigerant flowing out of the receiver 5 enters the indoor throttle mechanisms 6A and 6B through the liquid refrigerant pipe 12 and is adiabatically expanded by being throttled there to become a gas-liquid two phase. The gas-liquid two-phase refrigerant enters the indoor heat exchangers 7A and 7B, where the indoor air blown by the indoor blowers 9A and 9B is cooled and evaporated and vaporized. This gas refrigerant is sucked into the compressor 1 through the indoor switching valves 8A and 8B, the suction pipe 11, and the accumulator 14.

When all or some of the indoor units A, B, C are operated for heating, for example, when the indoor units A, B are operated for heating and the indoor unit C is stopped, the outdoor expansion mechanism 4, the room The inner throttle mechanisms 6A and 6B are set to a predetermined opening, and the indoor throttle mechanism 6C is fully closed. Then, the outdoor switching valve 2 and the indoor switching valves 8A and 8B are switched in the opposite manner to that during the cooling operation. Thus, the refrigerant discharged from the compressor 1 is condensed and liquefied by the indoor heat exchangers 7A and 7B via the indoor discharge pipe 10R and the outdoor switching valves 8A and 8B, and the indoor throttle mechanism 6
After being throttled by A and 6B, it is adiabatically expanded by the outdoor side throttle mechanism 4 via the liquid refrigerant pipe 12 and the receiver 5. Next, after evaporating and vaporizing in the outdoor heat exchanger 3, the outdoor switching valve 2, the suction pipe 11,
It returns to the compressor 1 through the accumulator 14 in this order.

In the simultaneous cooling / heating operation, when the number of indoor units operated in cooling is equal to the number of indoor units operated in heating, for example, the indoor unit C is operated in cooling operation.
When the indoor unit A is in the heating operation and the indoor unit B is not in operation, the outdoor expansion mechanism 4 and the indoor expansion mechanism 6B are fully closed, and the indoor expansion mechanisms 6A and 6C are set to predetermined opening degrees. Then, the indoor switching valve 8A is switched to communicate with the discharge pipe 10, and the indoor switching valve 8C is switched to communicate with the suction pipe 11. Thus, the refrigerant discharged from the compressor 1 includes the indoor discharge pipe 10R, the indoor switching valve 8A, the indoor heat exchanger 7A, the indoor throttle mechanism 6A, the liquid refrigerant pipe 12, the indoor throttle mechanism 6C, and the indoor heat. Returning to the compressor 1 through the exchanger 7C, the indoor switching valve 8C, the suction pipe 11, and the accumulator 14 in this order.

In the simultaneous cooling and heating operation, when the number of indoor units to be cooled is larger than the number of indoor units to be heated, for example, the indoor units B and C are cooled and the indoor unit A is heated. At times, the outdoor side expansion mechanism 4 and the indoor side expansion mechanisms 6A6B, 6C are set to predetermined opening degrees. The outdoor switching valve 2 and the indoor switching valve 8A communicate with the discharge pipe 10, and the indoor switching valves 8B and 8C are suction pipes.
Switched to communicate with 11. Thus, the refrigerant discharged from the compressor 1 branches at the point P, and a part of it branches through the outdoor discharge pipe 10L, the outdoor switching valve 2, the outdoor heat exchanger 3, the outdoor throttle mechanism 4, and the receiver 5. Enter the liquid refrigerant pipe 12. The remaining portion enters the liquid refrigerant pipe 12 through the indoor discharge pipe 10R, the indoor switching valve 8A, the indoor heat exchanger 7A, and the indoor throttling mechanism 6A, and merges with the refrigerant branched earlier. Next, this refrigerant returns to the compressor 1 through the indoor expansion mechanisms 6B and 6C, the indoor heat exchangers 7B and 7C, the indoor switching valves 8C and 8C, the suction pipe 11, and the accumulator 14 in this order.

[0008]

During the simultaneous cooling and heating operation of the conventional air conditioner, for example, the indoor unit A is in the cooling operation, the indoor units B and C are in the heating operation, and the indoor unit B is in the heating operation, When the room temperature of the room in which C is installed reaches the set temperature and the indoor units B and C are turned off, the indoor blowers 9B and 9C are stopped, and the opening degree of the indoor throttle mechanisms 6B and 6C is Although becoming smaller, both of the indoor side switching valves 8B and 8C are still switched so as to communicate with the discharge pipe 10. Therefore, the indoor switching valve 8
Refrigerant that has passed through B and 8C with almost no condensation and liquefaction in the indoor heat exchangers 7B and 7C enters the liquid refrigerant pipe 12 through the indoor throttle mechanisms 6B and 6C, and the refrigerant with a large amount of this gas is in cooling operation Since it flows into the indoor unit A inside, there is a problem that the cooling capacity of the indoor unit A decreases.

[0009]

SUMMARY OF THE INVENTION The present invention has been invented to solve the above problems, and its gist is to provide a compressor and a discharge pipe connected to the discharge side of the compressor. An intake pipe connected to the suction side of the compressor, an outdoor heat exchanger, and an outdoor switching valve for selectively communicating the gas side of the outdoor heat exchanger with the discharge pipe or the intake pipe. ,
The outdoor side expansion mechanism arranged on the liquid side of the outdoor side heat exchanger, the plurality of indoor side heat exchangers, and the gas side of the plurality of indoor side heat exchangers to the discharge pipe or the suction pipe, respectively. An indoor-side switching valve that selectively communicates with each other, an indoor-side throttle mechanism provided on each of the liquid sides of the plurality of indoor-side heat exchangers, a liquid side of the outdoor-side throttle mechanism, and the plurality of indoor-side throttle mechanisms. And a liquid refrigerant pipe connecting the liquid side of the indoor side heat exchanger and the indoor side switching with respect to the outdoor unit including the compressor, the outdoor heat exchanger, the outdoor switching valve, and the outdoor expansion mechanism. A plurality of indoor units including a valve and an indoor throttle mechanism are connected in parallel via the discharge pipe, a suction pipe, and a liquid refrigerant pipe, and the plurality of indoor units are in a cooling operation, a heating operation,
In an air conditioner capable of simultaneous cooling and heating operation, a flow rate adjusting means is provided on the indoor side of the discharge pipe for adjusting the refrigerant flow rate according to the number of thermo-off indoor units during heating and cooling operation at the same time. It is in an air conditioner characterized by that.

The flow rate adjusting means may be composed of a flow rate control valve.

The flow rate adjusting means may be constituted by a parallel circuit of an electromagnetic opening / closing valve and a flow rate adjusting pipe.

[0012]

In the present invention, when the indoor unit during heating / cooling simultaneous operation and during the heating operation is thermo-off, the flow rate adjusting means corresponds to the number of indoor units thermo-offing the flow rate of the gas refrigerant flowing inside the discharge pipe. And adjust.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENT One embodiment of the present invention is shown in FIG. A flow rate control valve 15 is interposed in the indoor discharge pipe 10R, and this flow rate control valve 15 adjusts the refrigerant flow rate in accordance with the number of thermo-off indoor units during the heating operation during the simultaneous cooling / heating operation.
Other configurations are similar to those of the conventional one shown in FIG. 3, and corresponding members are designated by the same reference numerals.

Thus, during simultaneous cooling and heating operation of the air conditioner, for example, during the cooling operation of the indoor unit A, during the heating operation of the indoor units B and C, and during the heating operation, the indoor units B and C are not thermo-off. The flow control valve 15 is fully open.

Therefore, like the conventional one, the refrigerant gas discharged from the compressor 1 is branched at the point P, and a part of the refrigerant gas is discharged to the outdoor discharge pipe 10L, the outdoor switching valve 2, the outdoor heat exchanger 3, It flows into the indoor unit A 1 in the cooling operation through the outdoor side expansion mechanism 4, the receiver 5, and the liquid refrigerant pipe 12.

At the same time, the remaining refrigerant gas flows into the indoor units B and C during the heating operation via the indoor discharge pipe 10R and the flow control valve 15, and the indoor switching valves 8B and 8C and the indoor heat exchanger thereof. 7B, 7C, the indoor throttle mechanisms 6B, 6C, and the liquid refrigerant pipe 12 to flow into the indoor unit A in the cooling operation and branch off from the refrigerant branched earlier. The combined liquid refrigerant is the indoor throttle mechanism 6A, the indoor heat exchanger 7A, the indoor switching valve 8A, the suction pipe 11,
Return to the compressor 1 via the accumulator 14.

Since the flow control valve 15 is fully closed when all the indoor units B and C during the heating operation are thermo-off, the refrigerant gas discharged from the compressor 1 is discharged to the indoor side discharge pipe 10.
R does not flow into R, all of which pass through the outdoor discharge pipe 10L, the outdoor switching valve 2, the outdoor heat exchanger 3, the outdoor throttling mechanism 4,
It returns to the compressor 1 via the receiver 5, the liquid refrigerant pipe 12, the indoor expansion mechanism 6A of the indoor unit A during the cooling operation, the indoor heat exchanger 7A, the indoor switching valve 8A, the suction pipe 11, and the accumulator 14.

A flow control valve when one of the indoor units B and C during heating operation, for example, only B is thermo-off
The opening of 15 becomes smaller. Along with this, the indoor discharge pipe 10
Since the amount of gas refrigerant flowing into the indoor units B and C via R becomes small, the indoor side switching valve 8B and the indoor heat exchanger 7B of the indoor unit B that has been thermo-off pass through the indoor unit B with almost no condensation and liquefaction. The amount of the gas-rich refrigerant that flows into the liquid refrigerant pipe 12 via the throttle mechanism 6B also decreases.

On the other hand, as the opening of the flow control valve 15 becomes smaller, the amount of gas refrigerant flowing through the outdoor discharge pipe 10L increases, so that the amount of liquid refrigerant condensed and liquefied in the outdoor heat exchanger 3 increases. .

Thus, the indoor unit B which has been turned off
Since the amount of the refrigerant having a large amount of the gas flowing therethrough decreases and the amount of the liquid refrigerant condensed and liquefied in the outdoor heat exchanger 3 increases, the amount of the refrigerant flowing into the indoor unit A during the cooling operation has a large amount of the liquid. Therefore, the indoor unit A can exhibit a sufficient cooling capacity.

The same applies to the case where any indoor unit during the simultaneous cooling / heating operation is thermo-off.
Further, when the flow control valve 15 is fully opened, the cooling operation, the heating operation, and the cooling / heating simultaneous operation are performed as in the conventional case.

FIG. 2 shows a second embodiment of the present invention. In the second embodiment, instead of the flow rate control valve 15, an electromagnetic on-off valve 16 and a flow rate adjusting pipe such as a capillary tube 17 connected in parallel with the electromagnetic on-off valve 16 are provided in the indoor discharge pipe 10R. The solenoid opening / closing valve 16 is closed during simultaneous cooling / heating operation of the air conditioner, when the indoor unit during heating operation is thermo-off, and is open in other cases.

When the electromagnetic on-off valve 16 is closed, however, the flow rate of the refrigerant gas is reduced by passing through the capillary tube 17, so that the amount of the gas refrigerant flowing into the thermo-off indoor unit is reduced.

[0024]

According to the present invention, when the air conditioner is in the cooling / heating simultaneous operation, when the indoor unit in the heating operation is thermo-off, the amount of the gas refrigerant flowing inside the discharge pipe is thermo-off by the flow rate adjusting means. Adjust according to the number of units. Therefore, the amount of the gas-rich refrigerant flowing through the thermo-off indoor unit decreases, and the amount of the liquid-rich refrigerant flowing through the outdoor unit increases at the same time. Refrigerant can be flowed in, and a sufficient cooling capacity can be exerted.

[Brief description of drawings]

FIG. 1 is a system diagram showing a first embodiment of the present invention.

FIG. 2 is a partial system diagram showing a second embodiment of the present invention.

FIG. 3 is a system diagram of a conventional air conditioner.

[Explanation of symbols]

 1 compressor 10 discharge pipe 10R indoor discharge pipe 11 suction pipe O outdoor unit 2 outdoor switching valve 3 outdoor heat exchanger 4 outdoor throttle mechanism A, B, C indoor unit 6A, 6B, 6C indoor throttle mechanism 7A , 7B, 7C Indoor heat exchanger 8A, 8B, 8C Indoor switching valve 12 Liquid refrigerant pipe 15 Flow rate adjusting means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazumi Honma 1 Takamichi, Iwazuka-cho, Nakamura-ku, Nagoya-shi, Nagoya Research Laboratory, Mitsubishi Heavy Industries, Ltd. (72) Tokuji Asahina 1 Takamichi, Iwazuka-machi, Nakamura-ku, Nagoya Address Mitsubishi Heavy Industries, Ltd. Nagoya Research Center

Claims (3)

[Claims] 1. A compressor, a discharge pipe connected to a discharge side of the compressor, a suction pipe connected to a suction side of the compressor, an outdoor heat exchanger, and the outdoor heat exchanger. An outdoor switching valve for selectively communicating the gas side of the outdoor pipe with the discharge pipe or the intake pipe, an outdoor throttle mechanism arranged on the liquid side of the outdoor heat exchanger, and a plurality of indoor heat exchangers. An indoor-side switching valve that selectively connects the gas side of the plurality of indoor-side heat exchangers to the discharge pipe or the suction pipe, and a liquid-side of the plurality of indoor-side heat exchangers, respectively. An indoor side throttle mechanism, a liquid refrigerant pipe connecting the liquid side of the outdoor side throttle mechanism and the liquid side of the plurality of indoor side throttle mechanisms, the compressor, the outdoor heat exchanger, the outdoor side switching valve , Indoor side heat exchanger, indoor side switching valve, indoor side with respect to the outdoor unit incorporating the outdoor side expansion mechanism A plurality of indoor units having a throttling mechanism are connected in parallel through the discharge pipe, the suction pipe, and the liquid refrigerant pipe, and the plurality of indoor units can perform cooling operation, heating operation, and cooling / heating simultaneous operation air. In the harmony machine,
An air conditioner provided on the indoor side of the discharge pipe with flow rate adjusting means for adjusting the refrigerant flow rate in accordance with the number of thermo-off indoor units during the heating / cooling simultaneous operation. 2. The air conditioner according to claim 1, wherein the flow rate adjusting means is constituted by a flow rate control valve. 3. The air conditioner according to claim 1, wherein the flow rate adjusting means is constituted by a parallel circuit of an electromagnetic opening / closing valve and a flow rate adjusting pipe.