JPH03294754A - Air conditioner - Google Patents

Abstract

PURPOSE:To perform concurrent condensing operations at different condensing temperatures and to improve a heat dissipating efficiency by connecting first, second compressors in series with first, second conduits, connecting a pressure reduction valve and an evaporator in series with a third conduit, and connecting the first, second conduits in parallel with the third conduit. CONSTITUTION:An outdoor heat exchanger 12 and an outdoor motor-driven expansion valve 13 for regulating its refrigerant flow rate are provided at the discharge side of a first compressor 11, and they are connected in series in a first conduit 14. A water heat exchanger 22 as a second condenser and a chilled water side motor-driven expansion valve 23 are provided at the discharge side of a second compressor 21, and they are connected in series in a second conduit 24. Further, an indoor heat exchanger 23 as an evaporator and an indoor motor-driven expansion valve 33 as a pressure reducing valve are connected in series in a third conduit 34. The conduits 14, 24 are composed in parallel with the conduit 34 to form a refrigerant circuit 1. Accordingly, if required capacity is large, the compressors 11, 21 are operated, while if the capacity is small, only one compressor is operated.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to two condensers arranged in a refrigerant circuit, each having a compressor connected in series.

(Prior Art) Conventionally, as disclosed in Japanese Patent Publication No. 58-48823, two air heat exchangers and two water heat exchangers are connected in parallel to two compressors. The refrigerant circuit has a refrigerant circuit whose connection relationship is variably connected, and the condenser and evaporator functions of each air heat exchanger and water heat exchanger can be variably switched according to the air conditioning load. There is a known technology that attempts to store heat in cold and hot water and utilize heat storage by performing simultaneous evaporation operation and simultaneous condensation operation with a heat exchanger, thereby reducing the electricity cost of air conditioners. be.

(Problem to be Solved by the Invention) However, in the above-mentioned conventional device, when simultaneous condensing operation is performed using an air heat exchanger and a water heat exchanger to use both the air and cold water as a condensing heat source, the heat source temperature When there is a large difference between the two temperatures, it is necessary to match the condensing temperature to the higher temperature. Therefore, in a water heat exchanger with a low condensing temperature, there is no choice but to operate with liquid refrigerant accumulated in a part of the water heat exchanger. However, there was a problem in that the capabilities of the device could not be used effectively.

The present invention has been made in view of the above, and its purpose is to perform simultaneous condensing operation at different condensing temperatures in each condenser by connecting a compressor to each of the two condensers in series. The aim is to improve the efficiency of capacity utilization.

(Means for Solving the Problems) In order to achieve the above object 1, the solving means of the present invention provides a first compressor (11
) and the first condenser (12) are connected in series, and the second compressor (21) and the first condenser (
12) is connected in series with a second condenser (22) having a different condensing temperature.
) and the evaporator (32) are connected in series (
Refrigerant circuit (1) connected in parallel to the refrigerant circuit (1)
The configuration is such that the

As shown in FIG. 2, the second solution is to change the refrigerant circuit (1) so that the first condenser (12) in the first solution is used as an evaporator and the evaporator (32) is used as a condenser. A cycle switching mechanism (2) for switching the refrigerant circulation cycle is provided.

A third solution, as shown in FIG. 3, uses a regenerative heat exchanger as the second condenser (22) in the first or second solution.

In addition, the suction pipe of the second compressor (21) and the regenerative heat exchanger (
22) and the gas pipe of the regenerative heat exchanger (22) to the second compressor (21).
A heat storage switching mechanism (26) is provided to selectively connect the discharge pipe and the branch path (25).

Furthermore, the above 1. Second compressor (11), (21
) and a check valve (4) that is interposed in the bypass path (3) and allows only the flow of refrigerant from one side to the other. It is something.

As shown in FIG. 4, a fourth solution means includes an ice heat storage tank (5), an ice heat storage tank (5)
and a circulation means (50) for circulating the liquid between the storage heat exchanger (22) and the heat storage heat exchanger (22).

(Function) With the above configuration, in the invention of claim (1), when the air conditioner is operating, the first
．． The overall capacity is adjusted by operating the second compressors (11) and (21) simultaneously or independently.

In that case, since compressors (11) and (21) are connected in series to each condenser (12) and (22), condensation heat sources with different temperatures, such as air and cold water, can be used simultaneously. In this case, each conduit (14),
Since it is possible to operate the condensing temperature in (24) at different temperatures commensurate with the respective heat source temperatures, the capacity can be fully utilized.

In the invention of claim (2), in addition to the effect of the invention of claim (1), by switching the cycle switching mechanism (2),
Since the first condenser (12) also functions as an evaporator, the second condenser (22) recovers the cold heat of cold water or generates hot water to perform indoor cooling and heating operations. It becomes possible to switch between operation and operation.

In the invention of claim (3), the second condenser (22) becomes a heat storage heat exchanger, and can function as a condenser or an evaporator by switching the heat storage switching mechanism (26), so it functions as an evaporator. While sometimes applying cold heat to the heat storage medium in the heat storage tank, when functioning as a condenser, it is possible to condense the refrigerant using the cold heat stored in the heat storage tank.

Conversely, when storing warm heat in a heat storage tank, it can also be used for storing warm heat and extracting warm heat.

In that case, a bypass path (3) connecting the discharge pipes of each compressor (11) and (21) is provided, and a non-return check is provided in the bypass path (3) to allow refrigerant to flow only from one side to the other. Since the valve (4) is provided, the amount of heat released or absorbed can be adjusted according to changes in the heat source while preventing the refrigerant from flowing from the side where the condensing temperature or evaporation temperature is higher to the side where the temperature is lower. This will improve the usability of heat storage.

In the invention of claim (4), while cold heat is stored in the ice heat storage tank (5) at night, during the day the cold heat stored in the storage heat exchanger (22) and the heat radiated to the atmosphere outside the room are used to store the refrigerant. By performing the condensing action of the compressor (11,),
(21) While adjusting the capacity to the minimum value and actively utilizing nighttime power, the total power cost is reduced.

(Example) Hereinafter, an example of the present invention will be described based on the drawings.

FIG. 1 shows an air conditioner according to a first embodiment of the invention as claimed in claim (1), in which (11) is a first compressor, and (12) is arranged on the discharge side of the first compressor (11). an outdoor heat exchanger that exchanges heat between the refrigerant and outdoor air; (13) is an outdoor electric expansion valve that adjusts the refrigerant flow rate of the outdoor heat exchanger (12); (13) is the first conduit (14
) are connected in series.

Further, (21) is a second compressor, and (22) is a second compressor arranged on the discharge side of the second compressor (21) and connected to a cold water source.
A water heat exchanger as a condenser (23) is a water heat exchanger (
22) is a cold water side electric expansion valve that adjusts the refrigerant flow rate, and the above-mentioned devices (21) to (23) are connected in series in the second pipe line (24).

Further, (32) is an indoor heat exchanger that functions as an evaporator, (33) is an indoor electric expansion valve that is a pressure reducing valve that reduces the pressure of the refrigerant, and each of the above devices (32) to (33) is connected to a third pipe. are connected in series in the line (34).

The first pipe line (14) and the second pipe line (24) are connected in parallel to the third pipe line (34) so as to form a closed circuit, and the refrigerant circulates through the refrigerant. Circuit (1
) is configured.

Therefore, in the invention of claim (1), when the required indoor capacity is large during operation of the air conditioner, the first. The first and second compressors (11) and (21) are operated in the second pipes (14) and (24), respectively, and the refrigerant discharged from each compressor (11) and (21) is transferred to the outdoor heat exchanger. (12) and the water heat exchanger (22), then merge into the third pipe (34), reduce the pressure with the indoor electric expansion valve (33), and evaporate in the indoor heat exchanger (32). When the required capacity on the indoor side is small, only one of the compressors (11) and (21) is operated to meet the required capacity on the indoor side and the water heat exchanger. (22) The capacity can be adjusted according to the amount of heat of the cold water source.

In that case, compressors (11) and (21) are connected in series to each heat exchanger (12) and (22), respectively, so when condensing heat sources having different temperatures, such as air and cold water, are used at the same time, Each pipe (14), (24)
It becomes possible to operate with different condensation temperatures. For example, if the atmospheric temperature is 30°C and the chilled water temperature is 0°C, in order to simultaneously use two condensers connected in parallel to -1 compressors, the condensing temperature Because it was necessary to keep the temperatures the same, it was necessary to operate according to the higher temperature. Therefore, the lower temperature heat exchanger (water heat exchanger (2, 2) in the above example) will be operated with liquid refrigerant partially accumulated, and the equipment will not be able to fully utilize its capabilities. 0 I couldn't do anything.

In contrast, in the present invention, each conduit (14).

Since the condensing temperature in (24) can be adjusted to match the temperature of each heat source, its capacity can be fully utilized. In particular, it is possible to reduce the power consumption of the compressor with a lower condensing temperature (the second compressor (21) in this embodiment).

In the above embodiment, the outdoor heat exchanger (12) was arranged in the first pipe line (14), and the indoor heat exchanger (32) was arranged in the third pipe line (34), but the present invention The present invention is not limited to this embodiment, and the first condenser (12) may be an indoor heat exchanger and the evaporator (32) may be an outdoor heat exchanger. In that case, it becomes possible to use the water heat exchanger (22) to generate hot water for hot water supply (for example, hot water temperature 60°C) while heating the room (for example, indoor temperature 25°C). There are advantages.

Next, regarding the second embodiment according to the invention of claim (2),
explain. FIG. 2 shows the refrigerant piping system of the air conditioner 1 button device according to the second embodiment.
In addition to the configuration of the first embodiment shown in the figure, an outdoor heat exchanger (1
A four-way switching valve (2) serves as a cycle switching mechanism that alternately switches the gas pipe of 2) and the gas pipe of the indoor heat exchanger (32) to the discharge side or suction side of the compressor (11), (21). It is provided. In other words, the refrigerant circulation cycle is switched by switching the four-way switching valve (2), and the four-way switching valve (2) switches the refrigerant circulation cycle.
2) switches to the solid line side in the figure, the outdoor heat exchanger (
12) functions as a condenser and the indoor heat exchanger (32) functions as an evaporator, while when the four-way selector valve (2) switches to the broken line side in the figure, the outdoor heat exchanger (12) functions as an evaporator and indoor heat exchanger (32) functions as an evaporator. A heat exchanger (32) is adapted to function as a condenser.

Therefore, in the invention of claim (2), the above claim (1)
In addition to the above invention, since the outdoor heat exchanger (12) can also function as an evaporator, the water heat exchanger (22) can be used as a heat source by exchanging heat with cold water, or as a user for producing hot water. It has the advantage of being able to switch between cooling and heating operations indoors while using the system.

Next, a third embodiment according to the invention of claim (3) will be described.

FIG. 3 shows a refrigerant piping system of an air conditioner according to a third embodiment. In the configuration of the air conditioner of the second embodiment shown in FIG. 2, a heat storage tank (not shown) is used as a water heat exchanger. A thermal storage heat exchanger (22) is arranged to exchange heat with the thermal storage medium. Furthermore, a branch line (25) bypass-connects the gas pipe of the regenerative heat exchanger (22) and the suction pipe of the second compressor (21), and a gas pipe of the regenerative heat exchanger (22) is connected to the second compressor (21). A heat storage switching valve (26) as a heat storage switching mechanism that alternately communicates with the discharge pipe of the compressor (21) and the branch path (25).
is provided. The heat storage switching valve (26) uses three ports of the four-way switching valve, and the heat storage switching valve (26) uses three ports of the four-way switching valve.
26) is switched to the solid line side in the figure, the gas pipe of the regenerative heat exchanger (22) communicates with the branch path (25) side, that is, the suction side of the first compressor (11), and the regenerative heat exchanger (22) ) functions as an evaporator, while when the heat storage switching valve (26) is switched to the middle broken line side in Figure 3, the gas pipe of the heat storage heat exchanger (22) communicates with the discharge pipe of the second compressor, and the heat storage Exchanger (
22) is adapted to function as a condenser. Note that (C) is a capillary tube interposed in the pipe on the dead boat side of the heat storage switching valve (26).

Further, a bypass passage (3) is provided that connects the discharge pipes of the first compressor (11) and the second compressor (2]), and the bypass passage (3) is provided with a bypass passage (3) that connects the discharge pipes of the first compressor (11) and the second compressor (2). ) is provided with a check valve (4) that allows refrigerant to flow only from the discharge pipe side of the first compressor (11) to the discharge pipe side of the first compressor (11).

That is, the outdoor heat exchanger (12) and the regenerative heat exchanger (2)
2) functions as a condenser, the regenerative heat exchanger (22)
When the condensation temperature and pressure become high, the amount of heat released can be distributed by releasing the gas discharged from the second compressor (21) to the outdoor heat exchanger (12).

In the above embodiment, the check valve (4) is connected to the second compressor (21).
) was installed so as to only allow refrigerant flow from the discharge pipe side of the first compressor (11) to the discharge pipe side of the first compressor (11).
The present invention is not limited to such embodiments; for example, when the regenerative heat exchanger (22) is used for hot water supply,
Since the condensation temperature is always high on the storage heat exchanger (22) side, the direction of the check valve (4) is opposite to that of the above embodiment.

Therefore, in the invention of claim (3), the heat storage switching valve (2
By switching 6), the storage heat exchanger (22) functions as a condenser or an evaporator, so when it functions as an evaporator, it transfers cold heat (=1
On the other hand, when the thermal storage heat exchanger (22) functions as a condenser, it becomes possible to condense the refrigerant using the cold heat stored in the thermal storage tank. Conversely, when storing warm heat in a heat storage tank, it can also be used for storing warm heat and extracting warm heat.

In that case, a bypass passage (3) is provided that connects the discharge pipes of each compressor (] ), (21), and a reverse passageway that allows refrigerant to flow only from one side to the other is provided in the bypass passage (3). Since a stop valve (4) is provided5, the amount of heat released or absorbed is adjusted according to changes in the heat source while preventing the refrigerant from flowing from the side where the condensing temperature or evaporation temperature is higher to the side where it is lower. There are possible advantages.

Next, a fourth embodiment according to the invention of claim (4) will be described.

FIG. 4 shows a refrigerant piping system of an air conditioner according to a fourth embodiment. In addition to the configuration of the air conditioner of the third embodiment shown in FIG. 3, a plurality of indoor heat exchangers (32), (32)
Further, an ice heat storage tank (5) for storing water or an aqueous solution as a heat storage medium is arranged. The ice heat storage tank (5) and the heat storage heat exchanger (22) are connected by a water pipe (6) so that water can be circulated, and the water pipe (6) is connected to the water pipe (6). A pump (7) is provided. The water pipe (6) and the pump (7) constitute a circulation means (50) that circulates the liquid between the ice heat storage tank (5) and the thermal storage heat exchanger (22).

That is, the thermal storage heat exchanger (22) performs heat exchange between the cold water (thermal storage medium) in the ice storage tank 6 (5) and the refrigerant, thereby generating ice in the ice storage tank (5) or converting the cold heat stored by ice making into ice. By condensing the refrigerant using
It is designed to meet the required indoor capacity.

Therefore, in the invention of claim (4), as shown in FIG. 5, cold heat is stored in the ice heat storage tank (5) at night (in the figure,
On the other hand, during the day the heat storage heat exchanger (2
The condensation action of the refrigerant is performed by utilizing the stored cold heat in 2) (horizontal hatched area ■ in the figure) and the heat radiation to the atmosphere in the outdoor heat exchanger (12) (unhatched area ■ in the figure). This makes it possible to actively utilize nighttime power while reducing the capacity of the compressors (11) and (21).

That is, as shown in FIG. 6, the compressor (11) during the daytime
The operating capacity of (21) decreases linearly as the cold storage heat utilization rate increases (see the solid line Ω1 in the figure), but on the other hand,
The operating capacity of the compressors (11) and (21) during the night increases linearly with the increase in the storage heat utilization rate (see the broken line Ω2 in the figure), considering the recovery efficiency of cold storage heat (refer to the broken line Ω2 in the figure), and the rate of increase is On the contrary, it increases more than the rate of decrease during the daytime (difference between point A and point B in the figure).

In that case, taking into account that nighttime power is cheap, the cost of power eventually becomes minimum at the intersection C between the solid line ρ1 and the broken line Ω2.

Therefore, when recovering the cold heat stored in the ice storage tank (5), the outdoor heat exchanger (12) and the storage heat exchanger (22) are operated at different condensing temperatures, thereby reducing the electricity cost as described above. Simultaneous condensing operation can be performed at point C, where is the minimum, and it is possible to improve the efficiency of nighttime power usage.

(Effects of the Invention) As explained above, according to the invention of claim (1), the first compressor and the first condenser are connected in series to the first conduit, and the second condenser is connected to the second conduit. While the compressor and the second condenser are connected in series, the pressure reducing valve and the evaporator are connected in series to the third pipe line, and the first pipe line and the second pipe line are connected to the third pipe line. Since the condensers are connected in parallel, each condenser can perform simultaneous condensing operation at different condensing temperatures, thereby making it possible to effectively utilize the available heat source or improve the efficiency of heat radiation to the heat radiation source.

According to the invention of claim (2), in addition to the invention of claim (1), the functions of the first condenser and the evaporator are switched, so that the second condenser radiates heat to the heat radiation source. Alternatively, there is an advantage that cooling operation and heating operation can be switched while absorbing heat from the heat absorption source.

According to the invention of claim (3), the above claim (1) or (
In the invention of 2), the second condenser is a regenerative heat exchanger that exchanges heat with the heat storage medium of the heat storage tank, and the regenerative heat exchanger can be switched to an evaporator and a condenser, and the discharge of each compressor is A bypass path is provided to connect the pipes, and a check valve is installed in the bypass path to allow refrigerant to flow only from one side to the other. While blocking the refrigerant flow, when the height of both is reversed, the refrigerant flows,
It is possible to distribute the heat radiation amount or the heat absorption amount, and therefore it is possible to improve the efficiency of capacity utilization.

9 According to the invention of claim (4), in the invention of claim (3), an ice heat storage tank is arranged, and a circulation means for circulating a liquid between the ice heat storage tank and the heat storage heat exchanger is provided. So,
By performing simultaneous condensing operation on the outdoor side and the storage heat exchanger during the day and using the cold storage heat at night, the operating capacity of the compressor can be controlled to the minimum, thereby improving power usage efficiency. I can do it.

[Brief explanation of drawings]

The drawings show embodiments of the present invention, FIG. 1 is a refrigerant piping system diagram showing the configuration of the air conditioner of the first embodiment according to the invention of claim (1), and FIG. Refrigerant piping system diagram showing the configuration of the air conditioner according to the second embodiment of the invention, No. 3
The figure is a refrigerant piping system diagram showing the configuration of the air conditioner according to the invention of claim (3), and FIG. 4 is the refrigerant piping system diagram showing the configuration of the air conditioner of the fourth embodiment according to the invention of claim (4). The system diagram, FIG. 5 is an explanatory diagram showing changes in the operating mode of the air conditioner between night and daytime, and FIG. 6 is a characteristic diagram showing changes in the operating capacity of the compressor with respect to changes in the heat storage utilization rate. 0 1 Refrigerant circuit 2 Four-way switching valve (cycle switching mechanism) 3 Bypass path 4 Check valve 5 Ice heat storage tank 11 First compressor 12 Outdoor heat exchanger (first condenser) 14 First pipe line 21 Second compression Machine 22 Thermal storage heat exchanger (second condenser) 24 Second pipe line 25 Branch line 26 Thermal storage switching valve (thermal storage switching mechanism) 32 Indoor heat exchanger (evaporator) 33 Indoor electric expansion valve 1 (pressure reducing valve) 34 No. 3 pipe line 50 circulation means 2

Claims (4)

[Claims] (1) A first conduit (14) formed by connecting a first compressor (11) and a first condenser (12) in series, and a second compressor (2
1) and the first condenser (12) are connected in series to a second condenser (22) having a different condensing temperature.
4) is provided with a refrigerant circuit (1) which is circularly connected in parallel to a third pipe line (34) formed by connecting a pressure reducing valve (33) and an evaporator (32) in series. An air conditioner featuring: (2) First condenser (12) as evaporator, evaporator (32)
Claim (1) further comprising a cycle switching mechanism (2) for switching the refrigerant circulation cycle of the refrigerant circuit (1) so that the refrigerant is used as a condenser.
) air conditioning equipment. (3) The second condenser (22) is a heat storage heat exchanger, and the second condenser (22) is a heat storage heat exchanger.
A branch line (25) bypass-connects the suction pipe of the compressor (21) and the gas pipe of the regenerative heat exchanger (22), and connects the gas pipe of the regenerative heat exchanger (22) to the second compressor (21). A heat storage switching mechanism (26) that selectively connects the discharge pipe to the branch path (25) is provided, and the discharge pipes of the first and second compressors (11) and (21) are connected to each other. Claim (1) or (2), comprising: a bypass passage (3) that allows refrigerant to pass through the bypass passage (3); and a check valve (4) that is interposed in the bypass passage (3) and that allows refrigerant to flow only from one side to the other. The air conditioner described. (4) An ice heat storage tank (5) and a circulation means (50) for circulating a liquid between the ice heat storage tank (5) and the heat storage heat exchanger (22).
The air conditioner according to claim (3), comprising: