JPH1130449A - Refrigerating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid a condition that lubricating oil is stayed in a part of compressors and faulty lubrication is generated in the other compressors, with respect to a refrigerant circuit equipped with a plurality of compressors. SOLUTION: A secondary refrigerant system, equipped with two sets of mutually independent primary side refrigerant circuits A, B and one set of secondary side refrigerant circuit C while permitting heat transfer between the primary side refrigerant circuits A, B and the secondary side refrigerant circuit C through intermediate heat exchangers 7A, 7B, connected in parallel, is constituted. Respective primary side refrigerant circuits A, B and respective intermediate heat exchangers 7A, 7B are received in an outdoor unit 1. Compressors 3A, 3B, equipped in respective primary side refrigerant circuits A, B, are provided with different operating capacity to permit the regulation of total capacity of the outdoor unit 1 by switching the starting and stopping of the compressors 3A, 3B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a refrigeration system,
In particular, the present invention relates to a measure for improving the reliability of a compressor provided with a refrigeration circuit having a plurality of compressors.

[0002]

2. Description of the Related Art Conventionally, for example, Japanese Patent Application Laid-Open No. 8-21071
A refrigeration circuit including a plurality of compressors is known as disclosed in Japanese Patent Application Publication No. 9-99. In this type of refrigeration circuit, for example, as shown in FIG. 10, two compressors (a1 and a2) are connected in parallel with each other to constitute a pseudo large-capacity compressor. That is, the discharge sides of the compressors (a1, a2) are connected to each other, and the four-way switching valve (b), the outdoor heat exchanger (c), the outdoor electric expansion valve (d), the indoor electric expansion valve (e), The indoor heat exchanger (f) is connected by a refrigerant pipe (g). In addition, one compressor (a1) has a constant operating capacity, while the other compressor (a2) is an inverter and the operating capacity of the entire compressor is variable.

At the time of indoor cooling operation, the four-way switching valve (b) is on the solid line side in the figure, and the refrigerant discharged from each compressor (a1, a2) is condensed in the outdoor heat exchanger (c). After the pressure is reduced by the indoor electric expansion valve (e), the indoor heat exchanger (f) evaporates and the compressor (a1, a2)
Return to Conversely, during indoor heating operation, the four-way switching valve (b)
Is on the broken line side in the figure, and the refrigerant circulates in the direction opposite to the above.

[0004]

In this type of refrigeration system, each compressor (a1, a2) discharges refrigerant and lubricating oil for compressor lubrication to circulate through the circuit. When the lubricating oil circulating in this circuit is collected by only one of the compressors, there is a possibility that the other compressor may run out of lubricating oil. In such a case, poor lubrication occurs in the other compressor, which significantly shortens the life of the compressor.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a refrigerant circuit having a plurality of compressors in which lubricating oil accumulates in some of the compressors and other oils are collected. An object of the present invention is to avoid a situation in which poor lubrication of a compressor occurs.

[0006]

In order to achieve the above-mentioned object, the present invention incorporates individual compressors into heat source circuits each having an independent closed circuit, and individually connects each of the heat source circuits to a user-side circuit. Heat exchange was performed to transfer heat between circuits.

Specifically, as shown in FIG. 1, the heat source side refrigerant means (A, B) for performing a vapor compression refrigeration cycle with the heat source side refrigerant and the utilization side heat exchanger (11) as shown in FIG. ) Having a use-side circuit means (C) in which the use-side refrigerant circulates, and the circuit means (A, B) which exchange heat with the refrigerant circulating through these circuit means (A, B) and (C). It is premised on a refrigerating device that transfers heat between B) and (C) and causes the use side heat exchanger (11) to perform a heat absorbing operation or a heat releasing operation. The above-mentioned heat source side circuit means is provided with a plurality of heat source side refrigeration circuits (A, B) comprising closed circuits independent of each other, and the heat source side refrigerant circulating through each heat source side refrigeration circuit (A, B) is used side circuit means. The heat exchange is performed individually with the use-side refrigerant of (C).

According to this specific matter, each heat source side refrigeration circuit
The heat source side refrigerants (A, B) perform a vapor compression refrigeration cycle operation while circulating through separate individual circuits, and exchange heat with the use side refrigerant of the use side circuit means (C). Thereby, the heat absorption operation or the heat radiation operation is performed in the use side heat exchanger (11) with the circulation of the use side refrigerant. Therefore, the heat source side refrigerant of each heat source side refrigeration circuit (A, B) does not mix with each other, and the lubricating oil mixed with this heat source side refrigerant and circulating in the circuit (A, B) is It is possible to avoid a biased flow in the refrigeration circuit.

According to the second aspect of the present invention, the heat exchange portions between the heat source side refrigerant and the use side refrigerant are connected in parallel to each other in the use side circuit means (C). That is, as shown in FIG. 1, the refrigeration apparatus according to claim 1 includes a plurality of intermediate heat exchangers (7A, 7B) for performing heat exchange between the heat source side refrigerant and the use side refrigerant. . In addition, the heat source side heat transfer portions (7a, 7a) of the intermediate heat exchangers (7A, 7B) are
7a), the use-side heat transfer sections (7b, 7b) of the intermediate heat exchangers (7A, 7B) are provided in the use-side circuit means (C). Further, the utilization side heat transfer sections (7b, 7b) of the intermediate heat exchangers (7A, 7B) are connected in parallel with each other.

According to this specific matter, the utilization side circuit means (C)
Is diverted to the use-side heat transfer sections (7b, 7b) of the intermediate heat exchangers (7A, 7B), and the heat-source-side refrigeration circuits (A, B)
After performing heat exchange with the heat source-side refrigerant, the merging flows toward the use side heat exchanger (11), and the use side heat exchanger (11)
Contributes to the heat absorbing operation or the heat radiating operation.

According to the third aspect of the present invention, the heat exchange portions of the heat source side refrigerant and the use side refrigerant are made common to each other. That is, in the refrigeration apparatus according to the first aspect, as shown in FIG. 2, an intermediate heat exchanger (7) for exchanging heat between the heat source side refrigerant and the use side refrigerant is provided. Heat source side heat transfer sections (7a, 7a) of intermediate heat exchanger (7) are connected to each heat source side refrigeration circuit (A, B).
The use side heat transfer section (7b) of the intermediate heat exchanger (7) is provided in the use side circuit means (C). Further, the heat source side heat transfer section (7a,
7a) and the use-side heat transfer section (7b) are housed inside one intermediate heat exchanger (7) so as to be able to exchange heat with each other.

According to this specific matter, each heat source side refrigeration circuit
There is no need to provide an intermediate heat exchanger for each of (A, B), and the number of parts can be reduced.

[0013] The invention of the following claims 4 to 9 is:
It specifies a compressor provided in each heat source side refrigeration circuit (A, B).

According to a fourth aspect of the present invention, in the refrigeration apparatus according to the first aspect, a part of the compressors (3A, 3B) provided in each of the heat source side refrigeration circuits (A, B) has a constant operating capacity. While the others are variable in operating capacity.

According to a fifth aspect of the present invention, in the refrigeration apparatus of the first aspect, the compressors (3A, 3B) provided in each of the heat source side refrigeration circuits (A, B) have a constant operating capacity. It is possible to switch between start and stop individually.

[0016] These specifics obviate the need to use an inverter for varying the operating frequency in at least some compressors. For this reason, it is possible to suppress problems caused by transmission of harmonics generated by the inverter to the transmission line via the power supply line. That is, it is possible to comply with the harmonic regulation. In the invention described in claim 4, each compressor (3A, 3A
By making part of B) a variable operating capacity (for example, an inverter type), it is possible to finely adjust the operating capacity of the entire compressor while minimizing the generation of harmonics.

According to a sixth aspect of the present invention, in the refrigeration system of the fifth aspect, each of the compressors (3A, 3B) has the same operating capacity.

According to a seventh aspect of the present invention, in the refrigeration system of the fifth aspect, each of the compressors (3A, 3B) has a different operation capacity.

The generation of harmonics can be prevented by these specific items. In the invention according to claim 7, each of the compressors
By switching the start and stop of (3A, 3B) individually, the capacity of the compressor as a whole can be switched in multiple stages,
Fine adjustment of the operating capacity of the compressor as a whole is possible as in the case of using a compressor with a variable operating capacity.

According to an eighth aspect of the present invention, in the refrigeration apparatus of the first aspect, each of the compressors (3A, 3B) has the same compression mechanism.

According to a ninth aspect of the present invention, in the refrigeration system of the first aspect, each of the compressors (3A, 3B) has a different compression mechanism.

With these specific items, a combination of a plurality of compressors can be embodied. In particular, according to the ninth aspect of the invention, if the start and stop of the compressors of different types are individually controlled, a compressor operating state optimal for the operating condition can be obtained. For example, it is possible to switch the operation state such as an operation state in which performance is emphasized and an operation state in which energy saving is emphasized.

According to a tenth aspect of the present invention, the arrangement of each heat source side refrigeration circuit is specified. That is, in the refrigeration apparatus according to the first aspect, each heat source side refrigeration circuit (A, B)
Are housed in the same casing (1).

According to this specific matter, it becomes possible to incorporate a plurality of heat source side refrigeration circuits (A, B) housed in the casing (1) into the apparatus as one unit. In this state,
When the operating capacity as a whole is changed by the control of each compressor, a unit with variable capacity can be obtained.

The following claims 11 to 13 are utilization side circuit means.
(C) specifies a means for obtaining a refrigerant circulation driving force.

According to an eleventh aspect of the present invention, in the refrigerating apparatus according to the first aspect, as shown in FIG. 1, the conveying means (C) for obtaining the circulation driving force of the use-side refrigerant in the use-side circuit means (C). 13), and the transport means is a mechanical pump (13).

According to a twelfth aspect of the present invention, in the refrigerating apparatus according to the second aspect, as shown in FIG. 3, the conveying means (C) for obtaining the circulation driving force of the use-side refrigerant to the use-side circuit means (C). 13) is provided. The transport means (13) includes at least one of a pressurizing means (21) for generating a high pressure by heating the liquid refrigerant and a depressurizing means (26) for generating a low pressure by cooling the gas refrigerant. This means (2
A difference between the pressure generated by 1) and (26) and the pressure in the use-side circuit means (C) generates a circulating drive force of the refrigerant.

According to these specific items, the user side circuit means
(C) means for obtaining the refrigerant circulation driving force is embodied. Particularly, in the twelfth aspect of the present invention, the circulation driving force is obtained by heating or cooling the refrigerant, so that there is no need to use mechanical means.

According to a thirteenth aspect of the present invention, in the refrigeration apparatus according to the first aspect, the use-side circuit means (C) is provided with a transport means (13) for obtaining a driving force for circulating the use-side refrigerant. Further, this transport means is constituted by a driving force generating circuit (13) capable of storing the liquid refrigerant. In the driving force generation circuit (13),
The heat exchange between the refrigerant of the heat source side refrigeration circuit (A, B) and the liquid refrigerant of the driving force generation circuit (13) is possible.
(C) a pressurizing means (21) for generating a high pressure by heating the liquid refrigerant of the driving force generation circuit (13) so as to push it out, and a driving force generation circuit for the liquid refrigerant of the utilization side circuit means (C). A pressure reducing means (26) for generating a low pressure by cooling the gas refrigerant of the driving force generation circuit (13) so that the gas refrigerant is sucked by the (13) is provided.

According to this specific matter, the refrigerant circulation operation is performed using the high pressure generated by the pressurizing means (21) and the low pressure generated by the depressurizing means (26). Therefore, a highly reliable refrigerant circulation operation can be performed.

According to the present invention, the arrangement state (number of arrangements) of the intermediate heat exchangers (7A, 7B), the pressurizing means (21) and the depressurizing means (26) is specified. .

The invention according to claim 14 is the invention according to claim 13.
In the refrigeration apparatus described, as shown in FIGS.
An intermediate heat exchanger (7A, 7B) is provided for each heat source side refrigeration circuit (A, B). On the other hand, the pressurizing means (21) is connected to each heat source side refrigeration circuit (A, B).
The liquid refrigerant of the driving force generation circuit (13) is heated by the refrigerant of a part of the heat source side refrigeration circuit (B).

[0033] The fifteenth aspect of the present invention is directed to the thirteenth aspect.
In the refrigeration apparatus described, as shown in FIGS.
An intermediate heat exchanger (7A, 7B) is provided for each heat source side refrigeration circuit (A, B). On the other hand, the pressure reducing means (26) is connected to each heat source side refrigeration circuit (A, B).
Of these, the gas refrigerant of the driving force generation circuit (13) is cooled by the refrigerant of a part of the heat source side refrigeration circuit (B).

[0034] The invention of claim 16 provides the above-mentioned claim 13.
In the refrigeration apparatus described above, as shown in FIG. 6, an intermediate heat exchanger (7A, 7B) is provided for each heat source side refrigeration circuit (A, B). On the other hand, the pressurizing means (21) is also provided for each heat source side refrigeration circuit (A, B), and heats the liquid refrigerant of the driving force generation circuit (13) by the refrigerant of each heat source side refrigeration circuit (A, B). It has a configuration.

According to a seventeenth aspect of the present invention,
In the refrigeration apparatus described above, as shown in FIG. 8, an intermediate heat exchanger (7A, 7B) is provided for each heat source side refrigeration circuit (A, B). On the other hand, the pressure reducing means (26) is also provided for each heat source side refrigeration circuit (A, B), and the gas refrigerant of the driving force generation circuit (13) is cooled by the refrigerant of each heat source side refrigeration circuit (A, B). And

According to these specific items, the intermediate heat exchanger (7A,
7B), the arrangement of the pressurizing means (21) and the pressure reducing means (26) is embodied.

The invention according to claims 18 and 19 further embodies the configuration of the driving force generation circuit (13), in which high pressure or low pressure is applied to the refrigerant stored in the tank means (T1, T2). Thereby, the refrigerant circulation driving force is obtained.

[0038] The invention of claim 18 provides the above-mentioned claim 13.
In the refrigeration apparatus described above, the driving force generation circuit (13) is provided with tank means (T1, T2) capable of storing a liquid refrigerant. The high pressure generated by the pressurizing means (21) due to the heating of the refrigerant is applied to the tank means (T
(T1, T2) and pressurize the liquid refrigerant from the tank means (T1, T2), and depressurize means (26) by cooling the refrigerant.
The low pressure generated in (1) is applied to the tank means (T1, T2) to recover the liquid refrigerant to the tank means (T1, T2), and the refrigerant is circulated to the utilization side circuit means (C) by the pressure reducing operation.

According to the nineteenth aspect of the present invention,
The first and second tank means (T1, T2) in which the tank means are connected in parallel to each other
Composed of Apply high pressure to the first tank means (T1) and
A first pressure action operation for applying a low pressure to the tank means (T2);
A second pressure action operation in which a low pressure is applied to the first tank means (T1) and a high pressure is applied to the second tank means (T2) is alternately switched. During the first pressure action operation, the first tank means (T
The liquid refrigerant is supplied from 1) to the heat exchangers (11) and (7b) serving as evaporators, and the second refrigerant is supplied from the heat exchangers (7b) and (11) serving as condensers.
While recovering the liquid refrigerant to the tank means (T2), during the second pressure action operation, the liquid refrigerant is supplied from the second tank means (T2) to the heat exchangers (11) and (7b) serving as evaporators. The refrigerant is circulated from the heat exchangers (7b) and (11) serving as condensers to the first tank means (T1) so as to collect the liquid refrigerant, and the use-side heat exchanger (1
1) The heat absorption or heat dissipation operation is performed continuously.

According to these specific items, the driving force generation circuit (1
3) can be made practical. In particular, in the invention according to claim 19, the liquid refrigerant is extruded from the one tank means,
Since the liquid refrigerant is recovered in the other tank means, heat absorption or heat radiation of the use side heat exchanger (11) is continuously performed. Therefore, when the present invention is applied to an air conditioner or the like, the indoor air-conditioning state can be favorably maintained for a long time.

According to a twentieth aspect of the present invention, in the refrigeration system according to the first aspect, the use-side heat exchanger is an indoor heat exchanger (11) arranged in an air-conditioned room, and the indoor air is cooled by a heat absorbing operation. In addition, the room air is heated by the heat radiation operation.

According to this specific matter, indoor air conditioning can be favorably performed.

[0043]

Embodiments of the present invention will be described below with reference to the drawings. This embodiment is a case where the refrigeration apparatus according to the present invention is applied to an air conditioner.

First Embodiment -Description of Refrigerant Circuit- First, a first embodiment will be described with reference to FIG. The air conditioner of the present embodiment is configured as a so-called indoor multi-unit including one outdoor unit (1) and two indoor units (2, 2). These units (1, 2) are connected by liquid-side and gas-side communication pipes (LL, LG).
That is, the liquid side communication pipe (the liquid refrigerant flows during the cooling operation)
The indoor side of (LL) is branched, and the gas side communication pipe (gas refrigerant flows during cooling operation) to the liquid side of each indoor unit (2, 2)
The indoor side of (LG) is also branched and connected to the gas side of each indoor unit (2, 2).

The outdoor unit (1) contains first and second primary refrigerant circuits (A, B) as heat source side refrigeration circuits. These primary refrigerant circuits (A, B) have the same configuration as each other, and include compressors (3A), (3B), four-way switching valves (4A), (4B), outdoor heat exchangers (5A), (5B), the outdoor electric expansion valves (6A) and (6B), and the heat exchanger 1 as a heat source side heat transfer section of the intermediate heat exchangers (7A) and (7B) described later.
Secondary heat transfer tubes (7a) and (7a) are connected by refrigerant pipes (8A) and (8B). Thereby, the four-way switching valve (4A), (4B)
Is switched to the state indicated by the solid line in the figure, the outdoor heat exchanger (5
A) and (5B) become condensers, and the primary heat transfer tubes (7a) and (7a) of the intermediate heat exchangers (7A) and (7B) become evaporators. Conversely, four-way switching valve
When (4A) and (4B) are in the switching state on the broken line side in the figure, the circulation direction of the refrigerant is switched, and one of the intermediate heat exchangers (7A) and (7B) is switched.
The secondary heat exchanger tubes (7a) and (7a) serve as condensers, and the outdoor heat exchanger (5
A) and (5B) are configurations that become evaporators.

Each indoor unit (2, 2) is an indoor electric expansion valve.
(10) and an indoor heat exchanger (11). The liquid side of the indoor electric expansion valve (10) is connected via a liquid side communication pipe (LL), and the gas side of the indoor heat exchanger (11) is connected via a gas side communication pipe (LG). 7A) and (7B) are connected to secondary heat transfer tubes (7b) and (7b) as use side heat transfer portions. That is, the outdoor side of the liquid side communication pipe (LL) and the gas side communication pipe (LG) is branched inside the outdoor unit (1), and the intermediate heat exchanger
The secondary heat transfer tubes (7b) and (7b) of (7A) and (7B) are connected to the liquid side and the gas side, respectively.

With such a configuration, each intermediate heat exchanger (7
In (A) and (7B), the primary heat transfer tube (7a) and the secondary heat transfer tube (7b)
Heat exchange is possible between the two. That is, heat exchange is performed between the refrigerant circulating in the first primary refrigerant circuit (A) and the refrigerant circulating in the secondary heat transfer tube (7b) of the first intermediate heat exchanger (7A), Further, heat exchange is performed between the refrigerant circulating in the second primary-side refrigerant circuit (B) and the refrigerant circulating in the secondary-side heat transfer tube (7b) of the second intermediate heat exchanger (7B). It has become. That is, the present refrigerant circuit is connected to a plurality of the heat exchangers via the intermediate heat exchangers (7A, 7B) connected in parallel with each other by the communication pipes (LL, LG).
A secondary refrigerant circuit (A, B) and a secondary refrigerant circuit (C) as a use side circuit means are connected so as to be able to carry heat.
It is constituted by a secondary refrigerant system.

The liquid side communication pipe (LL) is provided with a mechanical pump (13) as a transport means. By driving the pump (13), the circulation of the refrigerant in the secondary refrigerant circuit (C) is enabled.

The compressors (3A, 3B) provided in each of the primary-side refrigerant circuits (A, B) have a constant operating capacity (eg, operating frequency), and their operating capacity Are different from each other. That is, for example, the capacity of the first compressor (3A) provided in the first primary refrigerant circuit (A) is larger than the capacity of the second compressor provided in the second primary refrigerant circuit (B). The capacity of (3B) is set larger. For this reason,
The operating state is a state where only the first compressor (3A) is operating, a state where only the second compressor (3B) is operating, each compressor
Outdoor unit (1) in the order that (3A, 3B) are operating together
The ability as a whole is increasing.

-Description of Refrigerant Circulation Operation- Next, the refrigerant circulation operation of the present embodiment will be described. First,
During the indoor cooling operation, in the primary refrigerant circuit (A, B), each four-way switching valve (4A, 4B) is switched to the solid line side in the drawing, and each compressor (3A, 3B) is driven. I do. On the other hand, the pump (13) is driven in the secondary refrigerant circuit (C). This allows each circuit (A,
Refrigerant circulation in (B, C) is performed.

In each of the primary refrigerant circuits (A, B), the refrigerant discharged from the compressors (3A, 3B) is condensed in the outdoor heat exchangers (5A, 5B) as shown by solid arrows in FIG. And the outdoor electric expansion valve (6A, 6
After depressurizing in B), the primary heat transfer tube of the intermediate heat exchanger (7A, 7B)
In (7a, 7a), the refrigerant circulates in such a manner that heat is exchanged with the refrigerant circulating in the secondary refrigerant circuit (C) to evaporate and the refrigerant is sucked into the compressors (3A, 3B).

On the other hand, in the secondary-side refrigerant circuit (C), as shown by the dashed arrow in FIG. 1, the secondary-side heat transfer tubes (7b, 7b) of the intermediate heat exchangers (7A, 7B) The refrigerant condensed by performing heat exchange with the refrigerant circulating in the refrigerant circuit (A, B) is pumped (13)
Through the outdoor electric expansion valves (10, 10)
At (11, 11), heat exchange is performed with room air to evaporate. This cools the room air. Thereafter, the refrigerant returns to the secondary heat transfer tubes (7b, 7b) of the intermediate heat exchanger (7A, 7B) via the gas side communication pipe (LG). Such a refrigerant circulation operation is performed in the secondary refrigerant circuit (C).

In the refrigerant circulation operation in each of the circuits (A, B, C), the outdoor unit (1)
First, the first compressor (3A) is stopped. Thereby, heat exchange is not performed in the first intermediate heat exchanger (7A), and cold heat is given to the secondary-side refrigerant circuit (C) by heat exchange only in the second intermediate heat exchanger (7B). . Further, when the capacity of the outdoor unit (1) is reduced, the first compressor (3A) is driven and the second compressor (3
B) is stopped. Thereby, heat exchange is not performed in the second intermediate heat exchanger (7B), and cold heat is given to the secondary refrigerant circuit (C) by heat exchange only in the first intermediate heat exchanger (7A). . As described above, the capacity of the second compressor (3B) is set to be larger than the capacity of the first compressor (3A). Also, when only the first compressor (3A) is driven, the performance of the outdoor unit (1) is reduced. By switching the driving state of each compressor (3A, 3B) in this way,
It is possible to switch the capacity of the outdoor unit (1) in a plurality of stages.

Next, the operation during the indoor heating operation will be described. In this case, the four-way switching valves (4A, 4B) are in the switching state on the broken line side in the figure. Thereby, each primary refrigerant circuit (A,
In B), the refrigerant circulates in a direction opposite to the above. That is,
The refrigerant circulating in the primary refrigerant circuit (A, B) circulates in the secondary refrigerant circuit (C) in the primary heat transfer tubes (7a, 7a) of the intermediate heat exchanger (7A, 7B). The heat is exchanged with the refrigerant to condense and evaporate in the outdoor heat exchangers (5A, 5B).

On the other hand, in the secondary refrigerant circuit (C), the refrigerant circulating in the primary refrigerant circuit (A, B) in the secondary heat transfer tubes (7b, 7b) of the intermediate heat exchanger (7A, 7B). The liquid refrigerant heated by performing heat exchange with the outdoor electric expansion valve (10, 1) passes through the pump (13).
The flow rate is adjusted in 0), and heat is exchanged with indoor air in the indoor heat exchangers (11, 11). This heats the room air. Thereafter, the refrigerant returns to the secondary heat transfer tubes (7b, 7b) of the intermediate heat exchanger (7A, 7B) via the gas side communication pipe (LG). In this case, the liquid refrigerant flows through the gas side communication pipe (LG). Such a refrigerant circulation operation is performed in the secondary refrigerant circuit (C).

Even during the heating operation, when the capacity of the outdoor unit (1) is changed by changing the heating load, the start and stop of each compressor (3A, 3B) are controlled individually.

As described above, in the configuration of the present embodiment, each compressor
(3A, 3B) is a first primary refrigerant circuit (A) which is an individual closed circuit.
And the second primary refrigerant circuit (B). For this reason, a situation does not occur in which the lubricating oil discharged together with the refrigerant from one compressor is collected by the other compressor. For this reason, it is possible to avoid a situation in which the lubricating oil of the compressor runs short and causes poor lubrication, and it is possible to improve the reliability and extend the life of the compressor.

In the case of this embodiment, the capacity of the entire outdoor unit (1) can be varied by individually switching the start and stop of each compressor (3A, 3B). Therefore, capacity control becomes possible without providing an inverter compressor. As a result, generation of harmonics when using the inverter (harmonics generated by the inverter adversely affect the transmission line through the power line) can be suppressed, and each compressor can always be operated with high operation efficiency. And energy saving can be improved.

(Second Embodiment) Next, a second embodiment will be described with reference to FIG. This form is an outdoor unit
This is an improvement of the refrigerant circuit in (1). Other configurations are the same as those of the above-described first embodiment. Therefore, here, only the configuration of the outdoor unit (1) will be described.

In the outdoor unit (1) of this embodiment, the outdoor heat exchangers (5A, 5B) of the primary refrigerant circuits (A, B) are shared, and the intermediate heat exchangers (7A, 7B) ) Is also common. That is, one outdoor heat exchanger (5) and one intermediate heat exchanger (7) are arranged inside the outdoor unit (1), and each refrigerant pipe (8
A, 8B) are the common outdoor heat exchanger (5) and intermediate heat exchanger
Connected to (7). Further, inside the outdoor heat exchanger (5) and the intermediate heat exchanger (7), the first primary-side refrigerant circuit (A)
And the refrigerant in the second primary-side refrigerant circuit (B) flow through independent flow paths, and do not merge with each other.

With such a configuration, each primary refrigerant circuit
In (A, B), during the cooling operation (when the four-way switching valves (4A, 4B) are in the switching state of the solid line in the figure), the refrigerant discharged from each compressor (3A, 3B) is supplied to the outdoor heat exchanger. The refrigerant introduced into (5) is condensed, and the refrigerant evaporated in the intermediate heat exchanger (7) is cooled by the compressors (3A, 3B).
Inhaled. On the other hand, during heating operation (four-way switching valve (4A, 4B)
Is in the switching state indicated by the broken line in the figure), and each compressor (3A, 3B)
Is discharged into the intermediate heat exchanger (7) and condenses, and the refrigerant evaporated in the outdoor heat exchanger (5) is sucked into each of the compressors (3A, 3B).

As described above, according to the configuration of the present embodiment, the situation that the lubricating oil discharged together with the refrigerant from one compressor is collected by the other compressor does not occur. For this reason, it is possible to avoid a situation in which the lubricating oil of the compressor is insufficient and causes poor lubrication. In this embodiment, the outdoor heat exchanger (5) and the intermediate heat exchanger (7) are shared,
As in the first embodiment described above, each primary refrigerant circuit (A, B)
No separate heat exchanger is required for each. Therefore, the number of parts can be reduced, and the device can be made compact and the configuration of the entire circuit can be simplified.

(Third Embodiment) Next, a third embodiment will be described with reference to FIGS. In this embodiment, the configuration of the primary-side refrigerant circuit (A, B) and the configuration of the conveying means for obtaining the refrigerant circulation driving force in the secondary-side refrigerant circuit (C) are improved. Other configurations are the same as those of the above-described first embodiment.

-Description of Refrigerant Circuit- Among the primary refrigerant circuits (A, B) of the present embodiment, the first primary refrigerant circuit (A) is the same as that of the first embodiment described above. Therefore, the description here is omitted. On the other hand, the second primary-side refrigerant circuit (B) includes a check valve (CV-1) between the outdoor heat exchanger (5B) and the outdoor electric expansion valve (6B), and a driving heat heat exchanger described later. (2
The heat radiation part (21a) of 1) is provided. This check valve (CV-1)
Allows only the flow of refrigerant from the outdoor heat exchanger (5B) to the outdoor electric expansion valve (6B).

The heat radiating portion (2) of the driving heat exchanger (21)
The downstream side of 1a) and the suction side of the compressor (3B) are connected by a drive cooling line (25). This drive cooling line (2
5) is provided with an electric expansion valve (6C) and a heat absorbing portion (26a) of the driving cooling heat exchanger (26).

Further, in the second primary-side refrigerant circuit (B), between the intermediate heat exchanger (7B) and the four-way switching valve (4B), and the radiator ( The upstream side of 21a) is connected by a heating gas line (30). The heating gas line (30) has a radiator (21a) of a driving heating heat exchanger (21).
A check valve (CV-2) is provided to allow only the flow of the refrigerant toward the outlet. The heating liquid line (31) connects between the intermediate heat exchanger (7B) and the outdoor electric expansion valve (6B) and between the driving heating heat exchanger (21) and the outdoor heat exchanger (5B). Have been. The heating fluid line (31) is provided with a check valve (CV-3) and a capillary tube (CP) that allow only the flow of refrigerant from the intermediate heat exchanger (7B) to the outdoor heat exchanger (5B). Have been. A capillary tube (CP) is also provided between the primary heat transfer tube (7a) of the intermediate heat exchanger (7B) and the electric expansion valve (6B).

Next, a driving force generating circuit (13) as a transport means for obtaining a circulating driving force of the refrigerant circulating in the secondary refrigerant circuit (C) will be described. The driving force generating circuit (13) is connected to the liquid side communication pipe (LL) via a four-way switching valve (14). The driving force generating circuit (13) includes first and second tanks (T1, T2) as tank means.

Hereinafter, the circuit configuration of the driving force generating circuit (13) will be described. The driving heating heat exchanger (21) as a pressurizing means includes a heat absorbing section (21b), and the heat absorbing section (21b) can exchange heat with the heat radiating section (21a) of the main driving heating heat exchanger (21). It has become. A gas supply pipe (32) is connected to an upper end of the heat absorbing section (21b). This gas supply pipe (32) has two branch pipes (3
2a, 32b) and each is individually connected to the upper end of each tank (T1, T2). These branch pipes (32a, 32b) are provided with first and second tank pressurizing solenoid valves (SV-P1, SV-P2). In addition, this drive heating heat exchanger (21)
The liquid-side connection pipe (33) is connected to the lower end of the heat absorbing section (21b). This liquid side connection pipe (33) has two branch pipes (33a, 33
b) and each is individually connected to the lower end of each tank (T1, T2). Each of the branch pipes (33a, 33b) has a check valve (C) that allows only refrigerant to flow out of the tanks (T1, T2).
V-4, CV-4).

The driving heat exchanger (21) is installed at a position lower than each of the tanks (T1, T2). Therefore, in the normal state, the heat absorbing portion (21) of the driving heating heat exchanger (21)
Liquid refrigerant is present in b).

On the other hand, the driving cooling heat exchanger (26) as a pressure reducing means has a heat radiating portion (26b), and the heat radiating portion (26b) is a heat absorbing portion (26a) of the main driving cooling heat exchanger (26). Heat exchange is possible. A gas recovery pipe (34) is connected to the upper end of the radiator (26b). This gas recovery pipe (34) also has two branch pipes (3
4a, 34b), each of which is connected to the branch pipe (32a, 32b) of the gas supply pipe (32), whereby each tank (T1, T2)
Are individually connected to the upper end. Each branch pipe (34a, 34b) of the gas recovery pipe (34) is provided with first and second tank pressure reducing solenoid valves (SV-V1, SV-V2).

The radiating portion (26) of the driving cooling heat exchanger (26)
A liquid supply pipe (35) is connected to the lower end of b). The liquid supply pipe (35) is branched into two branch pipes (35a, 35b), each of which is connected to the branch pipe (33a, 33b) of the liquid-side connection pipe (33), thereby forming each tank (35). T1, T2) are individually connected to the lower end. The branch pipes (35a, 35b) of the liquid supply pipe (35) have check valves (CV-C) that allow only the recovery of refrigerant to the tanks (T1, T2).
5, CV-5). The drive cooling heat exchanger (2
6) is installed at a higher position than each tank (T1, T2). For this reason, in the normal state, the gas refrigerant exists in the heat radiating portion (26b) of the driving cooling heat exchanger (26).

As described above, in the refrigerant circuit of the present embodiment, the intermediate heat exchangers (7A, 7B) are provided for each of the primary refrigerant circuits (A, B).
A driving heating heat exchanger (21) and a driving cooling heat exchanger (26) are provided only in each second primary refrigerant circuit (B).

Further, two of the ports of the four-way switching valve (14) are connected to the liquid side communication pipe (LL), and the other port is connected to the other side.
One port is connected to a liquid recovery pipe (36). The liquid recovery pipe (36) is branched into two branch pipes (36a, 36b), each of which is connected to the branch pipe (33a, 33b) of the liquid-side connection pipe (33), whereby each tank ( T1, T2) are individually connected to the lower end. The branch pipes (36a, 36b) of the liquid recovery pipe (36) have check valves (CV-C) that allow only the recovery of the refrigerant to the tanks (T1, T2).
6, CV-6). The remaining one of the four-way switching valve (14)
The two ports are connected to the liquid side connection pipe (33) via a liquid pipe (37).

The above is the configuration of the refrigerant circuit of the air conditioner according to the present embodiment.

-Explanation of Refrigerant Circulation Operation- Next, an indoor cooling operation operation will be described. During this operation, first, each electric expansion valve (6A, 6B, 6C, 10) is adjusted to a predetermined opening. In addition, the pressurized solenoid valve (SV-
P1) and the pressure reducing solenoid valve (SV-V2) of the second tank (T2) are opened. On the other hand, the depressurizing solenoid valve (SV-V1) of the first tank (T1) and the pressurizing solenoid valve (SV-P2) of the second tank (T2) are closed.

In this state, the four-way switching valves (4A, 4B, 14) are switched to the solid line side in the drawing, and the primary refrigerant circuits (A, B)
, Each compressor (3A, 3B) is driven.

In the first primary refrigerant circuit (A), the refrigerant circulates in the first intermediate heat exchanger (7A) in the same manner as in the first embodiment described above, and the secondary refrigerant circuit (C) Gives cold to the refrigerant.

On the other hand, in the second primary-side refrigerant circuit (B), as shown by the solid arrows in FIG. 4, the high-temperature and high-pressure gas refrigerant discharged from the compressor (3B) passes through the outdoor heat exchanger (5B). After condensing by performing heat exchange with the outside air, the drive heat heat exchanger (21) exchanges heat with the refrigerant in the secondary refrigerant circuit (C) to be in a supercooled state. The refrigerant in the supercooled state is partially depressurized by the outdoor electric expansion valve (6B), and then gives cold heat to the refrigerant in the secondary refrigerant circuit (C) in the second intermediate heat exchanger (7B). It evaporates and is sucked into the compressor (3B). The other refrigerant flows through the drive cooling line (25) and is depressurized by the electric expansion valve (6C), and then the secondary refrigerant circuit in the drive cooling heat exchanger (26).
The refrigerant of (C) is cooled and evaporated to be sucked into the compressor (3B). Such a circulation operation is repeated.

The transfer of heat in the driving heating heat exchanger (21) and the driving cooling heat exchanger (26) causes the heat absorbing portion (21b) of the driving heating heat exchanger (21) to evaporate the refrigerant. As a result, a high pressure is generated, and a low pressure is generated in the heat radiating portion (26b) of the driving cooling heat exchanger (26) as the refrigerant condenses.

Therefore, the internal pressure of the first tank (T1) becomes high (pressurizing operation), and conversely, the internal pressure of the second tank (T2) becomes low (pressure reducing operation). Thereby, the secondary refrigerant circuit (C)
In FIG. 4, the liquid refrigerant pushed out from the first tank (T1) is supplied to one branch pipe (33a) of the liquid-side connection pipe (33) and the liquid pipe (37) as indicated by a broken arrow in FIG. ), After passing through the four-way switching valve (14) and the liquid side communication pipe (LL), the pressure is reduced by the indoor electric expansion valve (10, 10), and between the indoor heat exchanger (11, 11) and the indoor air. It performs heat exchange and evaporates to cool the room air. After that, this refrigerant passes through the gas side communication pipe (LG) and passes through each intermediate heat exchanger (7
A, 7B) cools and condenses in the heat radiating portions (7b, 7b). The condensed refrigerant passes through the liquid-side communication pipe (LL), the four-way switching valve (14), and one of the branch pipes (36b) of the liquid recovery pipe (36), and then flows into the second tank (T2).
Will be collected.

Since the driving heat exchanger (21) is installed at a position lower than each tank (T1, T2), a part of the liquid refrigerant pushed out from the first tank (T1) is reduced. The liquid-side connecting pipe (33) allows the heat-absorbing section (2
It is introduced in 1b) and contributes to high pressure generation. On the other hand, since the driving cooling heat exchanger (26) is installed at a position higher than each tank (T1, T2), the driving cooling heat exchanger (26) is recovered from the second tank (T2) and The liquid refrigerant condensed in the heat radiating portion (26b) is returned to the second tank (T2) by the liquid supply pipe (35).

After performing such an operation for a predetermined time, the solenoid valve of the driving force generating circuit (13) is switched. That is, the pressurizing solenoid valve (SV-P1) of the first tank (T1) and the depressurizing solenoid valve (SV-V2) of the second tank (T2) are closed. Further, the pressure reducing solenoid valve (SV-V1) of the first tank (T1) and the pressurizing solenoid valve (SV-V1) of the second tank (T2)
P2) is released.

As a result, the internal pressure of the first tank (T1) becomes low, and conversely, the internal pressure of the second tank (T2) becomes high. Therefore, the liquid refrigerant extruded from the second tank (T2) circulates in the same manner as described above, and enters a refrigerant circulation state in which the liquid refrigerant is collected in the first tank (T1).

By repeating the switching operation of each of the solenoid valves (SV-P1 to SV-V2) as described above, the secondary refrigerant circuit
In (B), the refrigerant is circulated, and the room is continuously cooled.

Next, the indoor heating operation will be described. Even during this operation, first, each electric expansion valve (6A, 6A
B, 6C) is adjusted to a predetermined opening. Also, the first tank (T1)
Pressure solenoid valve (SV-P1) and pressure reducing solenoid valve of the second tank (T2)
(SV-V2) is released. On the other hand, the pressure reducing solenoid valve (SV-V1) of the first tank (T1) and the pressurizing solenoid valve (SV-P2) of the second tank (T2)
Is closed.

In this state, the four-way switching valve (4A, 4B) is in the switching state on the broken line side in the figure, and in each primary refrigerant circuit (A, B), each compressor (3A, 3B) is Drive.

In the first primary refrigerant circuit (A), the refrigerant circulates in the first intermediate heat exchanger (7A) in the same manner as in the first embodiment described above, and the secondary refrigerant circuit (C) Heat to the refrigerant.

On the other hand, in the second primary-side refrigerant circuit (B), as shown by the solid arrow in FIG. 5, a part of the high-temperature and high-pressure gas refrigerant discharged from the compressor (3B) is subjected to the second intermediate heat exchange. In the vessel (7B), the refrigerant in the secondary refrigerant circuit (C) is heated and condensed.
This condensed refrigerant flows through the heating liquid line (31), is decompressed by the capillary tube (CP), and then evaporates by performing heat exchange with the outside air in the outdoor heat exchanger (5B) to evaporate, and the compressor (3B) Inhaled. The other refrigerant flows through the heating gas line (30), and gives heat to the refrigerant in the secondary refrigerant circuit (C) in the driving heating heat exchanger (21). After that, the refrigerant is decompressed by the electric expansion valve (6C), and is cooled by the secondary cooling circuit in the driving cooling heat exchanger (26).
Cold heat is given to the refrigerant of (C), and the refrigerant is sucked into the compressor (3B).
Such a circulation operation is repeated.

As described above, even in the heating operation, the heat absorption and reception of the driving heating heat exchanger (21) is performed by the transfer of heat in the driving heating heat exchanger (21) and the driving cooling heat exchanger (26). Two
In 1b), a high pressure is generated as the refrigerant evaporates, and a low pressure is generated in the radiator (26b) of the driving cooling heat exchanger (26) as the refrigerant is condensed.

Therefore, as in the case of the above-described cooling operation, the switching operation of each of the solenoid valves (SV-P1 to SV-V2) is performed, whereby the operation of pushing out the refrigerant from one tank and the other tank are performed. And the operation of collecting the refrigerant. That is, for example, as shown by a dashed arrow in FIG. 5, the liquid refrigerant extruded from the first tank (T1) is supplied to one branch pipe of the liquid side connection pipe (33).
(33a), liquid pipe (37), four-way switching valve (14), liquid side connecting pipe (L
After passing through L), they reach the intermediate heat exchangers (7A, 7B), exchange heat with the refrigerant in the primary refrigerant circuit (A, B), and evaporate. This evaporated refrigerant passes through the gas-side connection pipe (LG) and passes through the indoor heat exchanger.
(11, 11), heat exchange is performed with the room air, and the air is condensed to heat the room air. Thereafter, the refrigerant is circulated to the second tank (T2) via the liquid-side communication pipe (LL), the four-way switching valve (14), and one of the branch pipes (36b) of the liquid recovery pipe (36). Perform the operation.

Also in this case, the driving heat exchanger (21)
Is installed at a position lower than each tank (T1, T2), so that a part of the liquid refrigerant pushed out from the first tank (T1) is heated by the liquid side connection pipe (33). It is introduced into the heat absorbing portion (21b) of (21) and contributes to the generation of high pressure. On the other hand, since the driving cooling heat exchanger (26) is installed at a position higher than each tank (T1, T2), the driving cooling heat exchanger (26) is recovered from the second tank (T2) and The liquid refrigerant condensed in the heat radiating portion (26b) is returned to the second tank (T2) by the liquid supply pipe (35).

As described above, according to this embodiment,
A situation does not occur in which lubricating oil discharged together with the refrigerant from one compressor is collected by the other compressor. For this reason, it is possible to avoid a situation in which the lubricating oil of the compressor runs short and causes poor lubrication, and it is possible to improve the reliability and extend the life of the compressor.

Further, heat exchange between the refrigerant circulating in the second primary refrigerant circuit (B) and the refrigerant circulating in the secondary refrigerant circuit (C) causes the secondary refrigerant circuit ( The cooling power of each primary-side refrigerant circuit (A, B) is given to the secondary-side refrigerant circuit (C) while obtaining the driving force for circulating the refrigerant in (C), thereby cooling and heating the room. The second primary refrigerant circuit (B) has a function as a heat source for the secondary refrigerant circuit (C) and a secondary refrigerant circuit (B).
Since it also has a function as a driving heat source for obtaining the driving force for the refrigerant circulation in (C), it is possible to perform a good refrigerant circulation operation while minimizing the number of parts as necessary.

(Fourth Embodiment) Next, a fourth embodiment will be described with reference to FIGS. This embodiment is a modification of the above-described third embodiment. Therefore, here the third
Only differences from the embodiment will be described.

As shown in FIG. 6, the configuration of the second primary refrigerant circuit (B) of the primary refrigerant circuit (A, B) of this embodiment is the same as that of the third embodiment described above. It is.

On the other hand, the first primary-side refrigerant circuit (A) is provided between the outdoor heat exchanger (5A) and the outdoor electric expansion valve (6A) by the heat radiating portion (21a) of the driving heating heat exchanger (21A). ) And a check valve (CV-1A). This check valve (CV-1A)
This allows only the refrigerant to flow from the heat radiating portion (21a) of (21A) to the outdoor electric expansion valve (6A).

The heat radiating portion of the driving heating heat exchanger (21A)
Bypass line (4) connecting the upstream and downstream sides of (21a)
The bypass line (40) is provided with a check valve (CV-2A) that allows only refrigerant flow from the outdoor electric expansion valve (6A) to the outdoor heat exchanger (5A). Is provided.

On the other hand, in the driving force generating circuit (13), the heat absorbing portions (21b, 21b) of the driving heating heat exchangers (21A, 21B) are connected in parallel with each other. Other configurations are the same as in the third embodiment described above.

As described above, in the refrigerant circuit of this embodiment, the intermediate heat exchangers (7A, 7B) are provided for each of the primary refrigerant circuits (A, B).
Each first primary-side refrigerant circuit (A) has a driving heating heat exchanger (21).
A), a driving heating heat exchanger (21B) and a driving cooling heat exchanger (26) are provided for each second primary-side refrigerant circuit (B).

Next, the operation of this embodiment will be described. The refrigerant circulation operation in the second primary-side refrigerant circuit (B) is the same as that of the above-described third embodiment in both the cooling operation and the heating operation, and thus the description is omitted here.

On the other hand, as a refrigerant circulation operation in the first primary-side refrigerant circuit (A), during the cooling operation, a high-temperature and high-pressure gas refrigerant discharged from the compressor (3A) is discharged as shown by a solid line arrow in FIG. After performing heat exchange with the outside air in the outdoor heat exchanger (5A) and condensing, heat is exchanged with the refrigerant in the secondary-side refrigerant circuit (C) in the driving heating heat exchanger (21A). It goes into a supercooled state. The supercooled refrigerant is supplied to the outdoor electric expansion valve.
After the pressure is reduced in (6A), the refrigerant in the secondary refrigerant circuit (C) is evaporated by applying cold to the refrigerant in the first intermediate heat exchanger (7A).
Inhaled in A). Such a circulation operation is repeated.

On the other hand, during the heating operation, the high-temperature and high-pressure gas refrigerant discharged from the compressor (3A) flows through the secondary-side refrigerant circuit in the first intermediate heat exchanger (7A), as indicated by the one-dot chain line in FIG.
The refrigerant of (C) is heated and condensed. The condensed refrigerant is decompressed by the outdoor electric expansion valve (6A), passes through the bypass line (40), exchanges heat with the outside air in the outdoor heat exchanger (5A), evaporates, and is evaporated by the compressor (3A). Inhaled.

On the other hand, the operation of circulating the refrigerant in the secondary refrigerant circuit (C) is substantially the same as that of the third embodiment. In FIG. 7, arrows indicated by broken lines indicate a refrigerant flow during the cooling operation, and arrows indicated by two-dotted lines indicate a refrigerant flow during the heating operation. In this embodiment, two drive heating heat exchangers (2
1A, 21B) are connected in parallel.
Among the refrigerants circulating in the secondary refrigerant circuit (C), those that contribute to the extrusion of the refrigerant from the tanks (T1, T2) are the primary refrigerant circuits (A) in each of the driving heating heat exchangers (21A, 21B). , B).

(Fifth Embodiment) Next, a fifth embodiment will be described with reference to FIGS. This embodiment is also a modification of the above-described third embodiment. Therefore, here the third
Only differences from the embodiment will be described.

As shown in FIG. 8, the structure of the second primary-side refrigerant circuit (B) of the primary-side refrigerant circuit (A, B) of this embodiment is the same as that of the third embodiment described above. It is.

On the other hand, in the first primary refrigerant circuit (A), one end of a driving cooling pipe (41) is connected between the four-way switching valve (4A) and the suction side of the compressor (3A). ing. This drive cooling pipe (4
1) is provided with a heat absorbing portion (26a) of a driving cooling heat exchanger (26A) and an electric expansion valve (6D). The other end of the driving cooling pipe (41) is branched, and each branch pipe (41a, 41b) is connected to both sides of the indoor electric expansion valve (6A). Each branch pipe (41a, 4
1b) is provided with check valves (CV-7, CV-7) that allow only refrigerant flow toward the heat absorbing portion (26a) of the driving cooling heat exchanger (26A). Thus, in the refrigerant circuit of the present embodiment, the intermediate heat exchangers (7A, 7B) are provided for each of the primary refrigerant circuits (A, B), and each of the first primary refrigerant circuits (A) is provided. Is the drive cooling heat exchanger (26A)
However, a driving heating heat exchanger (21B) and a driving cooling heat exchanger (26) are provided for each second primary-side refrigerant circuit (B).

Next, the operation of this embodiment will be described. The refrigerant circulation operation in the second primary-side refrigerant circuit (B) is the same as that of the above-described third embodiment in both the cooling operation and the heating operation, and thus the description is omitted here.

On the other hand, as a refrigerant circulation operation in the first primary-side refrigerant circuit (A), during the cooling operation, a high-temperature and high-pressure gas refrigerant discharged from the compressor (3A) is discharged as shown by a solid arrow in FIG. After performing heat exchange with outside air in the outdoor heat exchanger (5A) and condensing, a part of the pressure is reduced by the indoor electric expansion valve (6A), and then the pressure is reduced in the first intermediate heat exchanger (7A). Secondary refrigerant circuit
Cold heat is given to the refrigerant of (C), and the refrigerant is sucked into the compressor (3A).
Other refrigerant flows through the drive cooling line (41), and the electric expansion valve
After the pressure is reduced in (6D), heat is exchanged with the refrigerant in the secondary refrigerant circuit (C) in the driving cooling heat exchanger (26A) to evaporate, and is sucked into the compressor (3A). Such a circulation operation is repeated.

On the other hand, during the heating operation, the high-temperature and high-pressure gas refrigerant discharged from the compressor (3A) passes through the secondary-side refrigerant circuit in the first intermediate heat exchanger (7A), as indicated by the one-dot chain line in FIG.
The refrigerant of (C) is heated and condensed. Part of the condensed refrigerant is depressurized by the outdoor electric expansion valve (6A), and
In (A), heat is exchanged with the outside air to evaporate, and the compressor (3A)
Inhaled. The other refrigerant flows through the drive cooling line (41), is depressurized by the electric expansion valve (6D), and is driven by the drive cooling heat exchanger (26).
In A), heat is exchanged with the refrigerant in the secondary refrigerant circuit (C) to evaporate, and the refrigerant is sucked into the compressor (3A). Such a circulation operation is repeated.

On the other hand, the refrigerant circulation operation in the secondary refrigerant circuit (C) is substantially the same as in the case of the third embodiment. In FIG. 9, arrows indicated by broken lines indicate refrigerant flows during the cooling operation, and arrows indicated by two-dot chain lines indicate refrigerant flows during the heating operation.

The intermediate heat exchanger of each embodiment described above
As (7), a plate heat exchanger or a shell and tube heat exchanger can be used.

Further, the compressors provided in the respective primary refrigerant circuits may have the same operating capacity.
In this case, the capacity of the entire outdoor unit can be adjusted stepwise by the number of compressors.

Examples of the type of the compression mechanism of these compressors include a reciprocating type, a rotary type, and a scroll type. Each of the compressors may be of the same type, or may be of a different type. It may be.

Further, in each of the embodiments described above, the case where the refrigerating apparatus according to the present invention is applied to an air conditioner has been described, but it is also possible to apply the present invention to other refrigerating apparatuses.

[0115]

As described above, according to the present invention, the following effects can be obtained.

According to the first aspect of the present invention, the heat source side refrigerating circuits (A, B) each having an independent closed circuit are provided, and the heat source side refrigerating circuits (A, B) and the use side circuit means (C) are provided. The heat transfer is performed individually between the circuits to perform heat transfer between the circuits. For this reason, the heat source side refrigerant circulating in each heat source side refrigeration circuit (A, B) is not mixed with each other. Therefore, it is possible to prevent the lubricating oil mixed with the heat source side refrigerant and circulating in the circuit (A, B) from flowing unevenly to one heat source side refrigeration circuit, and preparing for each heat source side refrigeration circuit (A, B). The lubricating property of the compressor thus obtained is sufficiently ensured, and the reliability of the operation and the life of the compressor can be improved.

According to the second aspect of the present invention, the intermediate heat exchangers (7A, 7B), which are heat exchange portions between the heat source side refrigerant and the use side refrigerant, are connected in parallel to each other in the use side circuit means (C). I have.

Further, the invention according to claim 3 provides an intermediate heat exchanger (7) which is a heat exchange part between each heat source side refrigerant and the use side refrigerant.
Are made common to each other.

According to these inventions, each heat source side refrigeration circuit (A,
The circuit configurations of B) and the use side circuit means (C) are embodied.
In particular, according to the third aspect of the present invention, each heat source side refrigeration circuit
It is not necessary to provide an intermediate heat exchanger separately for each of (A, B), the number of parts can be reduced, the apparatus as a whole can be made compact, and the practicality can be improved.

According to a fourth aspect of the present invention, each heat source side refrigeration circuit is provided.
Some of the compressors (3A, 3B) provided in (A, B) have a constant operating capacity, while others have a variable operating capacity.

According to a fifth aspect of the present invention, each heat source side refrigeration circuit is provided.
Each of the compressors (3A, 3B) provided in (A, B) has a constant operating capacity, and the start and stop can be switched individually.

According to these inventions, it is not necessary to use an inverter for varying the operating frequency in at least some of the compressors. Therefore, there is a problem that harmonics generated by the inverter are transmitted to the transmission line via the power supply line. Can be suppressed. In addition, the compressor can always be operated with high operation efficiency by not using the inverter, and the energy saving of the entire apparatus can be improved.

According to the invention of claim 6, each of the compressors (3A, 3B)
The respective operating capacities are set identical to each other.

The invention according to claim 7 is characterized in that each of the compressors (3A, 3B)
The respective operating capacities are different from each other.

According to these inventions as well, generation of harmonics can be prevented. In the invention according to claim 7, each compressor (3A,
By switching the start and stop of 3B) individually, the capacity of the compressor as a whole can be switched in a plurality of stages, and the operating capacity of the compressor as a whole can be reduced as in the case of using a compressor with a variable operating capacity. Adjustment is possible. Therefore, it is possible to realize the same operation state as the case where the inverter is used, while suppressing generation of harmonics.

According to the present invention, each compressor (3A, 3B)
Each has the same compression mechanism type.

According to the ninth aspect of the present invention, each of the compressors (3A, 3B)
Each of them has a different compression mechanism type.

According to the present invention, a combination of a plurality of compressors can be realized. In particular, according to the ninth aspect of the present invention, if the start and stop of the compressors of different types (rotary type and scroll type) are individually controlled, a compressor operating state optimal for the operating condition can be obtained. . For example, it is possible to switch the operation state such as an operation state where importance is placed on performance and an operation state where importance is placed on energy saving, and the practicality of the device can be improved.

According to the tenth aspect of the present invention, each heat source side refrigeration circuit (A, B) is housed in the same casing (1). This makes it possible to incorporate a plurality of heat source side refrigeration circuits (A, B) housed in the casing (1) into the device as one unit. In this state, when the operating capacity as a whole is changed by the control of each compressor, a unit with variable capacity is obtained.

According to the eleventh aspect, the use side circuit means is provided.
(C) transport means (1
3), and the transport means is a mechanical pump (13).

According to a twelfth aspect of the present invention, the conveying means (13)
And at least one of a pressurizing means (21) for generating a high pressure by heating the liquid refrigerant and a depressurizing means (26) for generating a low pressure by cooling the gas refrigerant. The difference between the pressure generated by the means (21), (26) and the pressure in the utilization-side circuit means (C) generates a refrigerant circulation driving force.

According to these inventions, means for obtaining the refrigerant circulation driving force in the use side circuit means (C) is embodied. In particular, in the twelfth aspect of the present invention, since the circulation driving force is obtained by heating or cooling the refrigerant, there is no need to use a mechanical means, and a transportation means having a small number of failure occurrence factor parts is obtained, and the refrigerant circulation operation is performed. Reliability can be improved.

According to a thirteenth aspect of the present invention, a driving force generating circuit is provided.
(13) A pressurizing means (21) for generating a high pressure by heating the liquid refrigerant, and a pressure reducing means (26) for generating a low pressure by cooling the gas refrigerant of the driving force generation circuit (13). Thus, the refrigerant circulation driving force is obtained by these pressures. For this reason, a more reliable refrigerant circulation operation can be performed.

According to the fourteenth to seventeenth aspects of the present invention, the arrangement state (number of arrangements) of the intermediate heat exchangers (7A, 7B), the pressurizing means (21) and the depressurizing means (26) is specified. The practicality of the device can be improved.

According to the present invention, the refrigerant circulating driving force is obtained by applying high pressure or low pressure to the refrigerant stored in the tank means (T1, T2) provided in the driving force generating circuit (13). I did it. Therefore, the driving force generation circuit (13)
Can be made practical. In particular, in the invention according to claim 19, since the liquid refrigerant is pushed out from one tank means and the liquid refrigerant is recovered in the other tank means, the heat absorption or heat absorption of the use-side heat exchanger (11) is achieved. Heat dissipation is performed continuously. Therefore, when the present invention is applied to an air conditioner or the like, the indoor air-conditioning state can be favorably maintained for a long time.

[0136] The invention according to claim 20 applies the present invention to an air conditioner. For this reason, indoor air conditioning can be satisfactorily performed by ensuring good reliability of the compressor.

[Brief description of the drawings]

FIG. 1 is a refrigerant piping system diagram of an air conditioner according to a first embodiment.

FIG. 2 is a diagram corresponding to FIG. 1 in a second embodiment.

FIG. 3 is a diagram corresponding to FIG. 1 in a third embodiment.

FIG. 4 is a diagram illustrating a refrigerant circulation operation during a cooling operation according to a third embodiment.

FIG. 5 is a diagram illustrating a refrigerant circulation operation during a heating operation in a third embodiment.

FIG. 6 is a diagram corresponding to FIG. 1 in a fourth embodiment.

FIG. 7 is a diagram illustrating a refrigerant circulation operation in a fourth embodiment.

FIG. 8 is a diagram corresponding to FIG. 1 in a fifth embodiment.

FIG. 9 is a diagram showing a refrigerant circulation operation in a fifth embodiment.

FIG. 10 is a diagram corresponding to FIG. 1 in the prior art.

[Explanation of symbols]

 (A, B) Primary side refrigerant circuit (heat source side refrigeration circuit) (C) Secondary side refrigerant circuit (use side circuit means) (1) Outdoor unit (3A, 3B) Compressor (7A, 7B) Intermediate heat exchange (7a) Primary heat transfer tube (heat source side heat transfer unit) (7b) Secondary heat transfer tube (use side heat transfer unit) (11) Indoor heat exchanger (use side heat exchanger) (13) Pump, Driving force generation circuit (transportation means) (21) Driving heating heat exchanger (pressurizing means) (26) Driving cooling heat exchanger (decompression means) (T1) First tank (tank means) (T2) Second Tank (tank means)

Claims (20)

[Claims] A heat source side circuit means (A, B) in which a heat source side refrigerant performs a vapor compression refrigeration cycle, and a use side circuit means (C) having a use side heat exchanger (11) and circulating the use side refrigerant. ) And
The refrigerant circulating in each of these circuit means (A, B) and (C) exchanges heat to transfer heat between the circuit means (A, B) and (C) to the use side heat exchanger (11). In a refrigerating apparatus that performs a heat absorbing operation or a heat releasing operation, the heat source side circuit means includes a plurality of heat source side refrigerating circuits (A, B) each having a closed circuit independent of each other.
A refrigeration apparatus characterized in that the heat-source-side refrigerant circulating through (A, B) individually exchanges heat with the use-side refrigerant of the use-side circuit means (C). 2. The refrigeration apparatus according to claim 1, further comprising a plurality of intermediate heat exchangers (7A, 7B) for exchanging heat between the heat source side refrigerant and the use side refrigerant. The circuit (A, B) uses the heat source side heat transfer section (7a, 7a) of the intermediate heat exchanger (7A, 7B), and the use side circuit means (C) uses the intermediate heat exchanger (7A, 7B). Side heat transfer sections (7b, 7b) are provided, and the use side heat transfer sections (7b, 7b) of the intermediate heat exchangers (7A, 7B) are connected in parallel with each other. Refrigeration equipment. 3. The refrigeration apparatus according to claim 1, further comprising an intermediate heat exchanger (7) for exchanging heat between the heat source side refrigerant and the use side refrigerant, wherein each heat source side refrigeration circuit (A, B) is the heat source side heat transfer section (7a, 7a) of the intermediate heat exchanger (7), and the use side circuit means (C) is the intermediate heat exchanger.
The heat-source-side heat transfer sections (7a, 7a) and the use-side heat transfer section (7b) are provided inside one intermediate heat exchanger (7). A refrigeration apparatus characterized in that the refrigeration apparatuses are housed so that they can exchange heat with each other. 4. The refrigerating apparatus according to claim 1, wherein the compressor (3A, 3B) provided in each of the heat source side refrigerating circuits (A, B).
A refrigeration system characterized in that some of them have a constant operating capacity, while others have a variable operating capacity. 5. The refrigerating apparatus according to claim 1, wherein the compressor (3A, 3B) provided in each of the heat source side refrigerating circuits (A, B).
Is a refrigeration system characterized in that the operating capacity is constant and start / stop can be switched individually. 6. The refrigeration system according to claim 5, wherein each of the compressors (3A, 3B) has the same operating capacity. 7. The refrigeration system according to claim 5, wherein each of the compressors (3A, 3B) has a different operation capacity. 8. The refrigeration system according to claim 1, wherein each of the compressors (3A, 3B) has the same type of compression mechanism. 9. The refrigerating apparatus according to claim 1, wherein each of the compressors (3A, 3B) has a different compression mechanism. 10. The refrigerating apparatus according to claim 1, wherein each heat source side refrigerating circuit (A, B) is housed in the same casing (1). 11. The refrigeration apparatus according to claim 1, wherein the use-side circuit means (C) is connected to a transfer means (13) for obtaining a circulating drive force of the use-side refrigerant. A refrigeration apparatus characterized by being a mechanical pump (13). 12. The refrigeration apparatus according to claim 2, wherein the use-side circuit means (C) is provided with a transfer means (13) for obtaining a circulating driving force of the use-side refrigerant. 13) includes at least one of a pressurizing means (21) for generating a high pressure by heating the liquid refrigerant and a depressurizing means (26) for generating a low pressure by cooling the gas refrigerant. A refrigerating apparatus characterized in that a circulating drive force of the refrigerant is generated by a difference between a pressure generated by the pressure in the utilization side circuit means (C) and a pressure in the utilization side circuit means (C). 13. The refrigeration apparatus according to claim 1, wherein the use-side circuit means (C) is provided with a transfer means (13) for obtaining a circulating driving force of the use-side refrigerant. Driving force generation circuit capable of storing liquid refrigerant (13)
The driving force generation circuit (13) is capable of exchanging heat with the refrigerant of the heat source side refrigeration circuit (A, B), and the driving force generation circuit (13)
Pressurizing means (21) for generating a high pressure by heating the liquid refrigerant of the driving force generation circuit (13) so as to push out the liquid refrigerant of the use side circuit means (C), and the use side circuit means (C) A driving force generation circuit so that the liquid refrigerant is sucked into the driving force generation circuit (13).
A refrigerating apparatus comprising: (13) a pressure reducing means (26) for generating a low pressure by cooling the gas refrigerant. 14. The refrigeration apparatus according to claim 13, wherein the intermediate heat exchanger (7A, 7B) is provided for each heat source side refrigeration circuit (A, B), while the pressurizing means (21) is The driving force generating circuit (13) is driven by the refrigerant of a part of the heat source side refrigerating circuits (B) of the respective heat source side refrigerating circuits (A, B).
A refrigerating apparatus for heating the liquid refrigerant. 15. The refrigeration apparatus according to claim 13, wherein the intermediate heat exchangers (7A, 7B) are provided for each heat source side refrigeration circuit (A, B), while the pressure reducing means (26) Driving force generation circuit (13) by refrigerant of a part of heat source side refrigerating circuit (B) of each heat source side refrigerating circuit (A, B)
A refrigeration apparatus for cooling a gas refrigerant. 16. The refrigerating apparatus according to claim 13, wherein the intermediate heat exchangers (7A, 7B) are provided for each heat source side refrigerating circuit (A, B), while the pressurizing means (21) is also provided. A refrigerating apparatus provided for each of the heat source side refrigerating circuits (A, B), wherein the refrigerant of the heat source side refrigerating circuits (A, B) heats the liquid refrigerant of the driving force generating circuit (13). . 17. The refrigeration apparatus according to claim 13, wherein the intermediate heat exchanger (7A, 7B) is provided for each heat source side refrigeration circuit (A, B), and the pressure reducing means (26) is also provided. A refrigerating apparatus provided for each heat source side refrigerating circuit (A, B), wherein a gas refrigerant of a driving force generating circuit (13) is cooled by a refrigerant of each heat source side refrigerating circuit (A, B). 18. The refrigeration apparatus according to claim 13, wherein the driving force generating circuit (13) is provided with tank means (T1, T2) capable of storing a liquid refrigerant, and pressurizing means (21) by heating the refrigerant. ) Is applied to the tank means (T1, T2) to push the liquid refrigerant out of the tank means (T1, T2), and the low pressure generated in the pressure reducing means (26) by cooling the refrigerant is applied to the tank. The refrigerant is circulated to the utilization side circuit means (C) by the pressure reducing operation of recovering the liquid refrigerant to the tank means (T1, T2) by acting on the means (T1, T2). Refrigeration equipment. 19. The refrigeration apparatus according to claim 18, wherein the tank means comprises first and second tank means (T1, T2) connected in parallel to each other, and applies a high pressure to the first tank means (T1). A first pressure action operation for applying a low pressure to the second tank means (T2), and a second pressure action operation for applying a high pressure to the second tank means (T2) while applying a low pressure to the first tank means (T1). Switch alternately,
During the first pressure action operation, the liquid refrigerant is supplied from the first tank means (T1) to the heat exchangers (11) and (7b) serving as evaporators, and the heat exchangers (7b) and ( 11), the liquid refrigerant is recovered from the second tank means (T2) to the second tank means (T2), and during the second pressure action operation, the heat exchanger (1
1) and (7b) are supplied with liquid refrigerant, and the refrigerant is circulated and used so that the liquid refrigerant is recovered from the heat exchangers (7b) and (11) serving as condensers to the first tank means (T1). A refrigeration system characterized by causing the side heat exchanger (11) to continuously perform heat absorption or heat radiation operation. 20. The refrigeration system according to claim 1, wherein the use-side heat exchanger is an indoor heat exchanger (1) disposed in an air-conditioned room.
1) A refrigeration apparatus characterized in that indoor air is cooled by an endothermic operation and indoor air is heated by a radiating operation.