JPH06257889A - Multi-temperature generator with vapor compression type refrigerating cycle - Google Patents

Abstract

PURPOSE:To obtain a multi-temperature generator in which three or more saturation temperatures necessary for cooling/ heating, hot water supply, ice cold storage, etc., can be simultaneously efficiently obtained in a cycle having a plurality of heat exchangers. CONSTITUTION:A first high pressure gas tube 61 is connected to a discharge side of a first compressor 1, a second high pressure gas tube 62 is connected to a discharge side of a second compressor 2 through a first switching vale 21, and a low pressure gas tube 63 is connected to suction sides of the compressors 1, 2. The other sides of the tubes and a liquid tube 64 are connected to heat exchangers 51a, 51b, 51c. The discharge side of the compressor 2 is connected to the tube 61 via a high pressure gas communicating tube 64 through a third switching valve 23, and the discharge side of the compressor 2 is connected to the suction side of the compressor l via a compressor communicating tube 66 through a fourth switching valve 24.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vapor compression refrigeration cycle multi-temperature generation circuit capable of simultaneously and efficiently obtaining many saturation temperatures such as heating and cooling, hot water supply, and low temperature.

[0002]

2. Description of the Related Art Conventionally, as a vapor compression type cycle of this type, for example, there is one described in Japanese Patent Application Laid-Open No. 1-167561. FIG. 86 is a configuration diagram of a refrigerant system of the conventional vapor compression cycle described in the above publication. In the figure, 1 is a compressor, 11 is an accumulator, 51a-51
c is a heat exchanger. Reference numeral 61 is a high pressure gas pipe connected to the discharge side of the compressor 1, 63 is a low pressure gas pipe connected to the suction side of the compressor 1 via the accumulator 11, and 64 is a liquid pipe. Further, the heat exchangers 51a to 51c include high pressure gas pipes 6
1. The low-pressure gas pipe 63 is an open / close valve 26a, 26b, 26c
And 28a, 28b, and 28c, and the liquid pipe 64 is an electronic expansion valve 31 which is a flow control valve.
They are connected via a, 31b, and 31c, respectively. The conventional vapor compression cycle configured as described above operates as follows. Here, the operation in which the heat exchanger 51a is an outdoor heat exchanger, the heat exchangers 51b and 51c are indoor heat exchangers, the indoor heat exchanger 51b is in a heating state, and the indoor heat exchanger 51c is in a cooling state will be described with reference to FIG. 87. To do.

The high-temperature, high-pressure refrigerant gas discharged from the compressor 1 flows from the high-pressure gas pipe 61 through the on-off valve 26b into the heating indoor heat exchanger 51b, and is condensed and liquefied. The liquid refrigerant is decompressed by the flow control valve 31b and flows into the liquid pipe 64. This refrigerant passes through the electronic expansion valves 31a and 31c to become a low-pressure two-phase state, and the outdoor heat exchanger 51a respectively.
To the heat exchanger 51c in the cooling room, evaporate into gas,
It returns to the compressor 1 through the low-pressure gas pipe 63 and the accumulator 11. An example of using a plurality of compressors is disclosed in Japanese Patent Laid-Open No. 20757/1992.

[0004]

Since the conventional cooling and heating system is configured as described above, each heat exchanger can obtain only one condensation temperature and one evaporation temperature,
Further, when the difference between the condensation temperature and the evaporation temperature is large, there are problems that the compression ratio increases and the efficiency decreases, and the discharge temperature increases. Especially when not only cooling and heating but also hot water supply and ice heat storage are performed in one cycle, a high hot water supply temperature cannot be obtained or efficiency is reduced. Further, even if there are a plurality of compressors and they are switched by the valve, it is only switching between the two fixed states and cannot be freely selected according to the installation conditions or the desire to change. There was such a problem.

The present invention has been made to solve the above problems, and in one vapor compression refrigeration cycle, depending on the function required for each heat exchanger to be freely selected,
It is an object of the present invention to provide a cycle in which a large number of saturation temperatures can be set in each heat exchanger, various types of cycles can be configured, and which is highly efficient and has a wide operating range.

[0006]

A multi-temperature generation circuit using a vapor compression refrigeration cycle according to the present invention is provided with a plurality of compressors which can be connected in series or in parallel via a plurality of on-off valves or check valves. And a plurality of gas pipes respectively connected to either one of the discharge side or each suction side of the compressor via the on-off valve or check valve, or directly, and each discharge side of the compressor or At least one other gas pipe directly connected to either the other of the suction sides via the on-off valve or the check valve, and the plurality of gas pipes and the other gas pipes via the on-off valve. A plurality of heat exchangers, one end of each of which is connected to the other, and the other end of which is connected to a common refrigerant pipe through which the refrigerant flows via the pressure reducing means.

The multi-temperature generation circuit according to the vapor compression refrigeration cycle of the present invention comprises first and second compressors, and a plurality of heat exchangers, one end of which is the discharge side or the suction side of the first compressor. The other end, a first high-pressure gas pipe having the other end connected to the plurality of heat exchangers via a switch, and one end connected to the discharge side of the second compressor via the first switch or One of the suction sides has the other end connected to the plurality of heat exchangers via a switch, and branches on the way to the suction side of the first compressor via a second switch or A second high-pressure gas pipe connected to either the other side of the discharge side, one end of which is connected to the other side of either the suction side or the discharge side of the second compressor, and the first compressor of the first compressor via a third switch. Connect to either the suction side or the discharge side and the other end through a switch. A low-pressure gas pipe connected to the plurality of heat exchangers, a liquid pipe connected to the plurality of heat exchangers via a refrigerant flow controller, and a discharge side of the second compressor via a fourth switch. Is connected to the suction side of the first compressor, and a compressor communication pipe for sending the discharge gas of the second compressor to the first compressor is provided.

Further, a high pressure gas communication for connecting the discharge side of the second compressor and the first high pressure gas pipe via the fifth switch to feed the discharge gas of the second compressor to the first high pressure gas pipe. Provide a pipe.

A first accumulator is provided in the low pressure gas pipes on the suction side of the first and second compressors, and a second accumulator is provided in the second high pressure gas pipes on the suction side of the first compressor.

Further, a bypass pipe connecting the liquid pipe and the first accumulator and having a sixth switch and a flow controller in the pipeline, a bypass pipe between the flow controller and the first accumulator, and the first compressor. Provide a heat exchange part for exchanging heat with the suction pipe.

The first compressor or the second compressor is a variable capacity compressor.

The multi-temperature generation circuit according to the present invention is provided with n-1 compressors in a vapor compression refrigeration cycle capable of simultaneously obtaining n saturation temperatures, and each compressor is provided with a plurality of on-off valves or Any saturation temperature that is connected in series or in parallel via a check valve, and has one end connected to each discharge or suction side of the compressor and the other end connected to multiple heat exchangers via open / close valves. Is provided with one gas pipe group having n gas pipes and one liquid pipe connected to the plurality of heat exchangers via a refrigerant flow control valve.

A multi-temperature generation circuit according to the present invention comprises a first compressor, a second compressor and a plurality of heat exchangers, and one end of the multi-temperature generation circuit discharges the first compressor via a first check valve. Side or suction side, the other end is a first gas pipe connected to the plurality of heat exchangers via an on-off valve, and one end is either the discharge side or the suction side of the second compressor. On the other hand, the other end is a second gas pipe connected to the plurality of heat exchangers through the on-off valve, one end is on either the suction side or the discharge side of the accumulator, and the other end is the on-off valve. A third gas pipe connected to a plurality of heat exchangers via a heat exchanger, a liquid pipe connected to the plurality of heat exchangers via a refrigerant flow controller, and the discharge side of the accumulator and the first and second And the suction side of the compressor are individually connected via the second and third check valves, It is obtained communicates serial first check valve outlet pipe of the first gas pipe and the second gas pipe via a first on-off valve.

The multi-temperature generation circuit according to the present invention includes a plurality of heat exchangers including a first compressor, a second compressor, a hot water heat exchanger, a bath reheating heat exchanger, an indoor heat exchanger, and an outdoor heat exchanger. And a heat exchanger for reheating the hot water, the other end of which is connected to either the discharge side or the suction side of the first compressor through the first check valve and the other end of which is connected through the opening / closing valve. A first gas pipe connected to the exchanger and the outdoor heat exchanger, respectively, and the one end portion is the second gas pipe.
Either the discharge side or the suction side of the compressor, the other end is the second gas pipe connected to the indoor heat exchanger and the outdoor heat exchanger via the on-off valve, and the one end is the suction side or the discharge of the accumulator. On the other side of the other side, the other end is connected to each of the plurality of heat exchangers via an on-off valve, and a third gas pipe is connected to each of the plurality of heat exchangers via a refrigerant flow controller. A liquid pipe to be connected is provided, and the discharge side of the accumulator and the suction sides of the first and second compressors are individually connected via second and third check valves, and the first gas is connected. The pipe on the outlet side of the first check valve and the second pipe
The gas pipe is communicated with the first open / close valve.

The multi-temperature generation circuit according to the vapor compression refrigeration cycle of the present invention has a first compressor, a second compressor, a plurality of heat exchangers, and one end on the discharge side of the first compressor. A high-pressure gas pipe having the other end connected to the plurality of heat exchangers via an on-off valve, one end on the discharge side of the second compressor via the first on-off valve, and the other end via the on-off valve. It is connected to the plurality of heat exchangers and branches from between the first on-off valve and the on-off valve to branch through the fifth on-off valve and the second check valve to the first
A medium-pressure gas pipe connected to the suction side of the compressor, one end of which is connected to the suction side of the second compressor, and a first check valve and a second opening / closing valve in this order to suction the first compressor. A low-pressure gas pipe connected to the side, the other end is connected to the plurality of heat exchangers via an on-off valve, a liquid pipe connected to the plurality of heat exchangers via a refrigerant flow controller, A high-pressure gas communication pipe that connects the discharge side of the first compressor and the discharge side of the second compressor via a third on-off valve, the discharge side of the second compressor, the first check valve, and the second A compressor communication pipe that connects between the open / close valves via a fourth open / close valve, a first bypass path from the medium pressure gas pipe to the liquid pipe via a seventh open / close valve, and a liquid pipe from the liquid pipe And a second bypass passage extending to the suction side of the first compressor via an eight-way on-off valve.

The multi-temperature generation circuit according to the vapor compression refrigeration cycle of the present invention has a first compressor, a second compressor, a plurality of heat exchangers, and one end on the discharge side of the first compressor. A high pressure gas pipe having the other end connected to the plurality of heat exchangers via an on-off valve, one end on the discharge side of the second compressor via the first on-off valve, and the other end via the on-off valve. The first heat exchanger is connected to the plurality of heat exchangers, and branches from between the first on-off valve and the on-off valve to branch through the fifth on-off valve and the second check valve.
A medium-pressure gas pipe connected to the suction side of the compressor, one end of which is connected to the suction side of the second compressor, and a first check valve and a second opening / closing valve in this order to suck the first compressor. A low-pressure gas pipe connected to the side, the other end is connected to the plurality of heat exchangers via an on-off valve, a liquid pipe connected to the plurality of heat exchangers via a refrigerant flow controller, A high-pressure gas communication pipe that connects the discharge side of the first compressor and the discharge side of the second compressor via a third opening / closing valve, the discharge side of the second compressor, the first check valve, and the second check valve. A compressor communication pipe connecting between the on-off valves via a fourth on-off valve, a first bypass path from the medium-pressure gas pipe to the liquid pipe via a refrigerant flow controller, and a first pipe from the liquid pipe to the liquid pipe. And a second bypass passage extending to the suction side of the first compressor via an eight-way on-off valve.

The multi-temperature generation circuit according to the vapor compression refrigeration cycle of the present invention includes a first compressor, a second compressor, a plurality of heat exchangers, one end of which is on the discharge side of the first compressor. A high pressure gas pipe having the other end connected to the plurality of heat exchangers via an on-off valve, one end on the discharge side of the second compressor via the first on-off valve, and the other end via the on-off valve. The first heat exchanger is connected to the plurality of heat exchangers, and branches from between the first on-off valve and the on-off valve to branch through the fifth on-off valve and the second check valve.
A medium-pressure gas pipe connected to the suction side of the compressor, one end of which is connected to the suction side of the second compressor, and a first check valve and a second opening / closing valve in this order to suck the first compressor. A low pressure gas pipe connected to the side, the other end is connected to the plurality of heat exchangers via an on-off valve, a liquid receiver connected to the plurality of heat exchangers via a refrigerant flow controller, A high-pressure gas communication pipe that connects the discharge side of the first compressor and the discharge side of the second compressor via a third opening / closing valve, the discharge side of the second compressor, the first check valve, and the second check valve. The compressor communication pipe that connects the on-off valves via the fourth on-off valve and the medium-pressure gas pipe to the seventh pipe.
A first bypass passage leading to the liquid receiver via an opening / closing valve and a second bypass passage leading from the liquid receiver to the suction side of the first compressor via an eighth opening / closing valve are provided. .

The multi-temperature generation circuit according to the vapor compression refrigeration cycle of the present invention is a first compressor having a first compressor, a second compressor, a plurality of heat exchangers, and a first opening / closing valve at one end. On the discharge side of the first compressor via a discharge pipe, the other end has a high-pressure gas pipe connected to the plurality of heat exchangers via an on-off valve, and a second end having a second on-off valve. On the discharge side of the second compressor via a discharge pipe, the other end is a medium pressure gas pipe connected to the plurality of heat exchangers via an on-off valve, and one end is a fourth pipe.
A low-pressure gas pipe connected to the plurality of heat exchangers via the on-off valve on the suction side of the second compressor via a second suction pipe having the on-off valve, and A liquid pipe connected to the heat exchanger via a refrigerant flow controller; a first suction pipe connecting the medium-pressure gas pipe to the suction side of the first compressor via a third opening / closing valve; A discharge-side connecting pipe that connects the first discharge pipe and the second discharge pipe via a seventh opening / closing valve and an eighth opening / closing valve, and the first suction pipe and the second suction pipe. A suction side connecting pipe connected via a ninth opening / closing valve and a tenth opening / closing valve, and a first bypass connecting the intermediate pressure gas pipe and the second suction pipe via a fifth opening / closing valve. With a tube,
A second bypass pipe connecting the low-pressure pipe and the first suction pipe via a sixth opening / closing valve, between the seventh opening / closing valve, the eighth opening / closing valve, and the ninth opening / closing valve, A third bypass pipe connecting between the 10 open / close valves via an 11th open / close valve;
A fourth bypass pipe connecting the second discharge pipe and the high-pressure gas pipe via a thirteenth on-off valve, and a twelfth on-off valve connecting the first discharge pipe and the medium-pressure gas pipe to each other. And a fifth bypass pipe connected via the above.

The multi-temperature generation circuit according to the vapor compression refrigeration cycle of the present invention includes a first compressor, a second compressor, a plurality of heat exchangers, a four-way valve, and a first opening / closing valve at one end. A high pressure gas pipe having the other end connected to the plurality of heat exchangers via an on-off valve and a second on-off valve at one end are provided on the discharge side of the first compressor via the first discharge pipe. The other end is connected to the plurality of heat exchangers via an on-off valve on the discharge side of the second compressor via the second discharge pipe, and is branched from the middle to be connected to the four-way valve. Medium pressure gas pipe, one end to the four-way valve, the other is a low-pressure gas pipe connected to the plurality of heat exchangers via the on-off valve, and the plurality of heat exchangers via the refrigerant flow controller A first suction pipe that connects the liquid pipe to be connected, the four-way valve, and the suction side of the first compressor via a third opening / closing valve. A second suction pipe connecting the four-way valve and a suction side of the second compressor via a fourth opening / closing valve, and a seventh opening / closing of the first discharge pipe and the second discharge pipe. A discharge side connecting pipe connected through the valve and the eighth opening / closing valve,
Between the suction side connecting pipe that connects the first suction pipe and the second suction pipe via the ninth opening / closing valve and the tenth opening / closing valve, and the seventh opening / closing valve and the eighth opening / closing valve. And a third bypass pipe connecting between the ninth on-off valve and the tenth on-off valve via an eleventh on-off valve, and the second discharge pipe and the high-pressure gas pipe on a thirteenth open / close A fourth bypass pipe connected via a valve, the first discharge pipe and the medium pressure gas pipe to the first
And a fifth bypass pipe connected through the on-off valve.

The multi-temperature generation circuit according to the vapor compression refrigeration cycle of the present invention includes a first compressor, a second compressor, a plurality of heat exchangers, a first four-way valve, and a second four-way valve. And one end is connected to the discharge side of the first compressor via the first discharge pipe to which the first four-way valve is connected, and the other end is connected to the plurality of heat exchangers via open / close valves. A high-pressure gas pipe, the other end is connected to the plurality of heat exchangers via an on-off valve, and a medium-pressure gas pipe is connected at one end to the suction side of the second compressor via a second on-off valve. A low-pressure gas pipe having the other end connected to the plurality of heat exchangers via an on-off valve, and a liquid pipe connected to the plurality of heat exchangers via a refrigerant flow controller to the second suction pipe. A first suction pipe connecting the low-pressure gas pipe and the first compressor via the second four-way valve; a discharge side of the second compressor; A first connecting pipe connecting between the first on-off valve and the first four-way valve, and the second four-way valve between the suction side of the second compressor and the second on-off valve. A second connecting pipe connecting the first connecting valve and the second connecting valve, a third connecting pipe connecting the first four-way valve and the second four-way valve via a third opening / closing valve, and from both sides of the third opening / closing valve. Branch, 4th on-off valve, 5th
And a fourth connecting pipe and a fifth connecting pipe respectively connected to one end of the medium pressure gas pipe via the on-off valve.

The multi-temperature generation circuit by the vapor compression refrigeration cycle of the present invention includes a first compressor, a second compressor, a hot water heat exchanger and a plurality of heat exchangers, and a first four-way valve. ,
A second four-way valve, a third four-way valve, one end on the discharge side of the first compressor, and the other end on the hot water supply heat exchanger and the first
High pressure gas pipe connected to the plurality of heat exchangers via the four-way valve and the third four-way valve, one end to the discharge side of the second compressor via the first opening / closing valve, and the other end to the first side. Medium pressure gas that is connected to the plurality of heat exchangers via the second four-way valve and the third four-way valve, and branches in the middle to connect to the suction side of the first compressor via the fifth on-off valve. The pipe, one end of which is connected to the suction side of the second compressor, the first check valve and the second opening / closing valve are connected in this order to the suction side of the first compressor, and the other end of which is the first A low pressure gas pipe connected to the plurality of heat exchangers via a four-way valve and a second four-way valve, and a hot water supply heat exchanger and the plurality of heat exchangers are connected via a refrigerant flow controller. A liquid pipe, a high-pressure gas communication pipe connecting the discharge side of the first compressor and the discharge side of the second compressor via a third opening / closing valve, and the second compressor A compressor communicating pipe for connecting the discharge side to the first check valve and the second on-off valve via the fourth on-off valve, in which with a.

[0022]

The multi-temperature generation circuit by the vapor compression refrigeration cycle of the present invention is capable of freely setting a large number of saturation temperatures simultaneously by switching more gas pipes than a compressor that can be connected in series and parallel.

Since the multi-temperature generation circuit by the vapor compression refrigeration cycle of the present invention is configured as described above, the desired operation mode (functions required for each heat exchanger such as cooling / heating, hot water supply, and ice storage). ), It is possible to set a large number of saturation temperatures for each heat exchanger. In addition, when the difference between the condensation temperature and the evaporation temperature is small or large, the operation of the first and second compressors can be selectively used in parallel or alone operation, or in series operation (two-stage compression operation), resulting in high efficiency. Cycle can be realized.

Since a high pressure gas communication pipe is provided,
The discharge gas of the second compressor can be added to the discharge gas of the first compressor to improve the condensation (or evaporation) capacity.

Further, since the accumulator is provided on the suction side of the compressor, it is possible to prevent the liquid from returning to the compressor at the time of start-up or switching the operation mode, protect the compressor, and adjust the amount of refrigerant.

Further, when the difference between the condensation temperature and the evaporation temperature is relatively large and the first and second compressors are operated in series, the first two-phase refrigerant having a low temperature flows through the bypass pipe in the heat exchange section. (High-stage side) Can cool the refrigerant gas sucked into the compressor,
The rise in discharge temperature can be prevented, and the operating range can be expanded.

By using the variable capacity compressor as the first or second compressor, the flow rate of the refrigerant at the set saturation temperature can be made variable, and the necessary capacity can be exhibited in each heat exchanger.

In the multi-temperature generation circuit according to the present invention, a plurality of on-off valves provided at both ends of the n gas pipes and the liquid pipes are switched to change each heat exchanger according to a desired operation mode. It is possible to set n saturation temperatures, and it is possible to realize a cycle with high efficiency and a wide operating range.

Further, the multi-temperature generation circuit according to the present invention has a large number of heat exchangers for each heat exchanger depending on a desired operation mode (functions required for each heat exchanger such as cooling and heating, hot water supply, and ice heat storage). Since the saturation temperature can be set, each operation mode can be efficiently realized by switching the first opening / closing valve.

Further, in the multi-temperature generation circuit according to the present invention, the first compressor and the second compressor can be selectively used by switching the first on-off valve, and the first to third gas pipes,
Since the setting of condensation and evaporation of each heat exchanger can be freely realized by switching the on-off valve that connects the liquid pipe and the hot water supply for reheating, indoor and outdoor heat exchangers, heating and hot water supply,
Simultaneous operation of two condensations such as heating and reheating can be performed, and a heat source such as hot water supply can be used even in the operation of one condensation and one evaporation, and a highly efficient cycle can be realized.

The multi-temperature generation circuit according to the vapor compression refrigeration cycle of the present invention is used for high-temperature hot water supply / heating simultaneous operation or ice heat storage / hot water simultaneous operation with a relatively large difference between the condensation temperature and the evaporation temperature and a relatively large compression ratio. In this case, the discharge temperature rise is prevented by performing a two-stage compression operation in which the discharge gas of the low-stage compressor is passed through the liquid pipe through the on-off valve to be cooled and then sucked into the high-stage compressor. Two condensation temperatures and one evaporation temperature can be efficiently obtained. When the difference between the condensation temperature and the evaporation temperature is relatively large and the compression ratio is relatively large, such as during ice cold storage / cooling / heating / hot water simultaneous operation, the discharge gas of the low-stage compressor is passed from the liquid pipe through the on-off valve. After the bypassed liquids are merged and cooled, a two-stage compression operation in which the high-stage compressor is sucked in is performed to prevent the discharge temperature from rising and to prevent a single condensation temperature and
Two evaporation temperatures can be obtained efficiently.

In the multi-temperature generation circuit by the vapor compression refrigeration cycle of the present invention, in the high temperature hot water supply / heating simultaneous operation in which the difference between the condensation temperature and the evaporation temperature is relatively large and the compression ratio is relatively large, the low stage side compressor is used. After the discharge gas of No. 2 is passed through the liquid pipe through the expansion valve and cooled, the two-stage compression operation in which it is sucked into the high-stage compressor is performed to prevent the discharge temperature from rising and
By optimally controlling the bypass amount to the high-stage side, it is possible to obtain a higher hot water supply pressure, secure the heating capacity at the same time, and efficiently obtain two condensation temperatures and one evaporation temperature. In the case of simultaneous ice cold storage / cooling / hot water supply operation where the difference between the condensation temperature and the evaporation temperature is relatively large and the compression ratio is relatively large, the discharge gas of the low-stage compressor is passed from the liquid pipe through the expansion valve. By performing a two-stage compression operation in which the bypassed liquid is combined and cooled, and then sucked into the high-stage compressor, the discharge temperature rise is prevented and at the same time the liquid bypass amount is optimally controlled. It is possible to obtain a higher condensation temperature while preventing liquid compression of the machine, and to efficiently obtain one condensation temperature and two evaporation temperatures.

The multi-temperature generation circuit using the vapor compression refrigeration cycle of the present invention is suitable for high-temperature hot water supply / heating simultaneous operation and ice heat storage / hot water simultaneous operation in which the difference between the condensation temperature and the evaporation temperature is relatively large and the compression ratio is relatively large. In this case, the discharge gas of the low-stage side compressor is passed through the liquid receiver through the on-off valve to perform the cooling and the gas-liquid separation at the same time, and then the high-stage side compressor is sucked to perform the two-stage compression operation. It is possible to obtain a higher condensation temperature while efficiently preventing discharge temperature rise and liquid compression of the high-stage compressor, and efficiently obtain two condensation temperatures and one evaporation temperature. The difference between the condensation temperature and the evaporation temperature is relatively large,
In the case of simultaneous ice cold storage / cooling / hot water supply operation with a relatively large compression ratio, the discharge gas of the low-stage compressor is combined with the liquid bypassed from the liquid receiver via the on-off valve to cool, By performing the two-stage compression operation in which the high-stage compressor is sucked, it is possible to prevent the discharge temperature from rising and obtain a higher condensation temperature, and efficiently obtain one condensation temperature and two evaporation temperatures. .

The multi-temperature generation circuit according to the vapor compression refrigeration cycle of the present invention has the first difference in the case of normal cooling and heating operation in which the difference between the condensation temperature and the evaporation temperature is relatively small and the compression ratio is relatively small. , The second compressor is operated in parallel or in isolation, and can be efficiently obtained in the same manner as a normal circuit.

The difference between the condensation temperature and the evaporation temperature is relatively large,
In the case of high-temperature hot-water supply operation with a relatively high compression ratio or simultaneous hot-water supply / ice heat storage operation, the first and second compressors are operated in series and the discharge gas of the low-stage compressor is set to the high-stage. By performing the two-stage compression operation in which the side compressor is sucked, two saturation temperatures can be obtained with a highly efficient operation suitable for a high compression ratio. Further, the first and second compressors can be switched between the low-stage side and the high-stage side depending on the operating state, so that highly efficient operation can be performed.

The difference between the condensation temperature and the evaporation temperature is relatively small,
In the case of simultaneous operation of heating and hot water supply where the compression ratio is relatively small, two compressors are operated in parallel and the condensing temperature of each compressor is changed to obtain two condensing temperatures and one condensing temperature. The evaporation temperature can be obtained efficiently. Further, since there are two compressors, it is possible to select a compressor depending on the operating load and obtain sufficient capacity.

The difference between the condensation temperature and the evaporation temperature is relatively large,
In the case of heating / high-temperature hot-water supply operation where the compression ratio is relatively large, the compressors are operated in series so that part of the gas discharged from the low-stage compressor is sucked into the high-stage compressor to supply hot water. A two-stage compressed refrigerant gas is used for the heating, and the rest of the discharge gas of the low-stage compressor is used for heating. In operation, two condensing temperatures and one evaporating temperature are obtained. Further, since the first compressor and the second compressor can be switched between the low-stage side and the high-stage side depending on the operating state, selection can be made according to the operating load and sufficient capacity can be obtained.

The difference between the condensation temperature and the evaporation temperature is relatively small,
In the case of simultaneous operation of cooling and ice storage with a relatively small compression ratio, two compressors are operated in parallel and the evaporation temperature of each compressor is changed to obtain two evaporation temperatures and one condensation. The temperature can be obtained efficiently. Also, the compressor is 2
Since it is a stand, the compressor can be selected depending on the operating load and sufficient capacity can be obtained.

The difference between the condensation temperature and the evaporation temperature is relatively large,
In the case of simultaneous operation of cooling, hot water supply, and ice heat storage with a relatively high compression ratio, two compressors are operated simultaneously, and the gas discharged from the low-stage compressor is sucked into the high-stage compressor, High efficiency is achieved by using the condensation temperature of the high-stage compressor for hot water supply, the evaporation temperature of the high-stage compressor for cooling, and the evaporation temperature of the low-stage compressor for ice heat storage. In operation, one condensation temperature and two evaporation temperatures are efficiently obtained. Also, when cooling and ice heat storage and heating and hot water supply are operated at the same time,
Waste heat from cooling or ice storage can be used for hot water supply, and a more efficient circuit can be realized.

Since the multi-temperature generating circuit by the vapor compression refrigeration cycle of the present invention is constructed as described above, the desired operation mode (functions required for each heat exchanger such as cooling / heating, hot water supply, and cold storage heat) ), It is possible to set three or more saturation temperatures for each heat exchanger. In addition, when the difference between the condensation temperature and the evaporation temperature is small or large, the operation of the first and second compressors can be selectively used in parallel or alone operation, or in series operation (two-stage compression operation), resulting in high efficiency. Cycle can be realized.

The difference between the condensation temperature and the evaporation temperature is relatively small,
In the case of a normal cooling and heating operation with a relatively small compression ratio, the first, second, and plural compressors are operated in parallel or individually, and the same efficiency can be obtained as in a normal cycle.

The difference between the condensation temperature and the evaporation temperature is relatively large,
In the case of high-temperature hot water supply operation with a relatively large compression ratio, hot water supply, and ice heat storage simultaneous operation, the first and second compressors are operated in series and the discharge of the second (low-stage side) compressor is performed. By performing the two-stage compression operation in which the gas is sucked into the first (higher-stage side) compressor through the compressor communication pipe, two saturation temperatures can be obtained in a highly efficient operation suitable for a high compression ratio.

The difference between the condensation temperature and the evaporation temperature is relatively small,
In the case of simultaneous heating / hot water supply operation with a relatively small compression ratio, the first and second compressors, for example, two compressors are operated in parallel, and the condensing temperature of each compressor is changed to obtain two The condensation temperature and one evaporation temperature are efficiently obtained.

The difference between the condensation temperature and the evaporation temperature is relatively large,
In the case of simultaneous heating / high-temperature hot water supply operation with a relatively high compression ratio, the first and second compressors, for example, two compressors are operated simultaneously, and the discharge gas of the second (low-stage side) compressor is Part of it is sucked into the first (higher-stage side) compressor through the compressor communication pipe, and the second-stage compressed refrigerant is used for hot water supply, and the second is used for heating.
By using the remaining refrigerant of the discharge gas of the (low-stage side) compressor, two condensation temperatures and one evaporation temperature can be efficiently obtained in a highly efficient operation.

The difference between the condensation temperature and the evaporation temperature is relatively small,
In the case of simultaneous operation of cooling and ice heat storage with a relatively small compression ratio, the first and second compressors, for example, two compressors are operated in parallel, and the evaporation temperature of each compressor is changed. One condensation temperature and two evaporation temperatures are efficiently obtained.

The difference between the condensation temperature and the evaporation temperature is relatively large,
In cases such as cooling, hot water supply, and ice heat storage simultaneous operation where the compression ratio is relatively large, the first and second compressors, for example, two compressors are operated simultaneously, and the second (low-stage side) compressor is operated. The discharge gas is sucked into the first (higher-stage side) compressor through the compressor communication pipe, the condensing temperature of the first (higher-stage side) compressor is used for hot water supply, and the first (higher-stage side) compressor is used for cooling. Side) compressor's evaporation temperature and ice heat storage uses the second (low-stage side) compressor's evaporation temperature to efficiently obtain one condensation temperature and two evaporation temperatures with high efficiency operation. To be

[0047]

【Example】

Example 1. FIG. 1 is a configuration diagram of a refrigerant system of a multi-temperature generation circuit by a vapor compression refrigeration cycle according to an embodiment of the present invention. In the figure, 1 is a first compressor, 2 is a second compressor, 1
1 is a first accumulator, 12 is a second accumulator,
51a, 51b, 51c are heat exchangers. 61 is the first
A first high-pressure gas pipe connected to the discharge side of the compressor 1, 62 is a first opening / closing valve 2 which is a first switch on the discharge side of the second compressor 2.
The second high-pressure gas pipe connected via 1 is a low-pressure gas pipe 63 connected to the suction side of the first compressor 1 via the first accumulator 11, and 64 is a liquid pipe. First compressor 1 and first
The low pressure gas pipe 63 between the accumulators 11 is provided with a second on-off valve 22 and a first check valve 41 that form a third switch. 23 is the third opening / closing of the fifth switch provided in the high pressure gas communication pipe 65 connecting the second high pressure gas pipe 62 and the first high pressure gas pipe 61 between the second compressor 2 and the first on-off valve 21. A valve 24 is a compressor communication connecting the high pressure gas communication pipe 65 between the second compressor 2 and the third on-off valve 23 and the low pressure gas pipe 63 between the second on-off valve 22 and the first check valve 41. A fourth opening / closing valve provided in the pipe 66, and in this case, the fourth opening / closing valve includes a second opening / closing valve, a fourth opening / closing valve, and a first check valve. 25
Is a fifth opening / closing valve provided in the second high-pressure gas pipe 62 between the second accumulator 12 and the branch point of the second high-pressure gas pipe 62 connected to the suction side of the first compressor 1, and 42 is the first Second high pressure gas pipe 6 between the compressor 1 and the second accumulator 12
In the second check valve provided in No. 2, the second switch is composed of the fifth switch valve 25 and the second check valve 42. Further, the heat exchangers 51a, 51b, 51c are provided with a first high pressure gas pipe 61, a second high pressure gas pipe 62, and a low pressure gas pipe 63, respectively.
a, 27a, 28a, 26b, 27b, 28b and 2
6, 27c and 28c are branched and connected, and the liquid pipe 64 is an electronic expansion valve 31a, 3 which is a refrigerant flow rate controller.
1b and 31c are connected respectively.

The multi-temperature generation circuit of the present invention has six operation modes as shown in Table 1. The six operation modes will be described below with reference to FIGS.

[0049]

[Table 1]

First, using the explanatory diagram showing the operating state of the multi-temperature generation circuit of this embodiment in FIG. 2, at the time of generating two temperatures, one condensation temperature and one evaporation temperature are generated, the condensation temperature and the evaporation The operation when the temperature difference is relatively small will be described. This operation mode is applied, for example, during normal cooling or heating.

FIG. 2 shows an example in which the heat exchanger 51a operates as a condenser, the heat exchanger 51b stops, and the heat exchanger 51c operates as an evaporator. The first opening / closing valve 21 and the fourth opening / closing valve 2 are shown.
4, fifth on-off valve 25, on-off valves 27a, 28a, 26b,
27b, 28b, 26c and 27c are in a closed state (filled in the figure). The first compressor 1 and the second compressor 2 are operated in parallel. The arrow indicates the flow of the refrigerant.

The high-temperature high-pressure refrigerant gas discharged from the second compressor 2 merges with the high-temperature high-pressure refrigerant gas discharged from the first compressor 1 in the first high-pressure gas pipe 61 through the high-pressure gas communication pipe 65, and the on-off valve is opened. It flows into the heat exchanger 51a through 26a and is condensed and liquefied. The liquid refrigerant flows through the electric expansion valve 31a into the liquid pipe 64, and then flows through the electric expansion valve 31c into a low-pressure two-phase state into the heat exchanger 51c to be vaporized and gasified. The gas refrigerant passes through the low pressure gas pipe 63, the first accumulator 11, and the first compressor 1 and the second compressor 1.
It is sucked into the compressor 2. Thus, in this operation mode, the heat exchanger 51a obtains the condensation temperature and the heat exchanger 51c obtains the evaporation temperature.

In FIG. 2, it is used as 1 condensation + 1 evaporation temperature at the time of cooling and heating. In this case, the discharge pressure is 16 to 21.
Kg / cm ² abs (condensation), suction pressure 4-6 Kg / c
The condition of m ² abs (evaporation) is general. Here, the case where the difference between the condensation temperature and the evaporation temperature is relatively small means that the compression ratio, that is, the discharge pressure / suction pressure is 6 or less. Generally, in cooling or heating, this compression ratio is the second highest when the load is low, and normally it is used at the maximum of the fourth to fifth highest.

If 51a is an indoor unit heat exchanger and 51c is an outdoor unit heat exchanger, the flow of FIG. 2 shows the case of heating operation. In the case of cooling, the opening / closing valve 26c opens, the opening / closing valves 27c, 28c close, 51a acts as an evaporator, the opening / closing valves 26a, 27a close, the opening / closing valve 28a opens, and 51a evaporates. It acts as a container (reverse of FIG. 2).

The difference between the condensation temperature and the evaporation temperature is relatively small,
In the case of a normal cooling and heating operation with a relatively small compression ratio, the first, second, and plural compressors are operated in parallel or individually, and the same efficiency can be obtained as in a normal cycle. Moreover, in the case of this example, the heat exchangers on the use side and the heat source side can be exchanged, and the system configuration can be freely selected.

Next, using the explanatory diagram showing the operating state of the multi-temperature generation circuit of this embodiment of FIG. 3, the condensation temperature and the evaporation temperature are generated at the time of generating two temperatures for generating one condensation temperature and one evaporation temperature. The operation when the temperature difference is relatively large will be described. This operation mode is applied, for example, to hot water supply or hot water supply + ice heat storage. FIG. 3 shows an example in which the heat exchanger 51a operates as a condenser, the heat exchanger 51b stops, and the heat exchanger 51c operates as an evaporator. The first opening / closing valve 21, the third opening / closing valve 23, and the fifth opening / closing valve 21 are shown. Valve 25, open / close valves 27a, 28a, 2
6b, 27b, 28b, 26c and 27c are in a closed state (filled in the figure). The first compressor 1 and the second compressor 2 are operated in series. The arrow indicates the flow of the refrigerant.

The refrigerant gas discharged from the second compressor 2 is
High-pressure gas communication pipe 65 and compressor communication pipe 6 branched from this
6 and is sucked into the first compressor through the fourth opening / closing valve 24 and the second opening / closing valve 22 and is compressed in two stages to become a high-temperature high-pressure refrigerant gas, which then flows into the first high-pressure gas pipe 61. This gas refrigerant flows into the heat exchanger 51a through the opening / closing valve 26a and is condensed and liquefied. This liquid refrigerant is used in the electric expansion valve 31.
flowing into the liquid pipe 64 through a, flowing into the heat exchanger 51c through the electric expansion valve 31c in a low-pressure two-phase state,
Evaporative gasification. The gas refrigerant passes through the low pressure gas pipe 63, the first accumulator 11, and is sucked into the second compressor 2. In this way, in this operation mode, the two-stage compression operation is performed, and the heat exchanger 51a obtains the condensation temperature and the heat exchanger 51c obtains the evaporation temperature.

In FIG. 3, 1 condensation + 1 at high temperature hot water supply + ice heat storage
Used as evaporation temperature, discharge pressure 26-27K
g / cm ² abs (1 condensation), suction pressure 3 Kg / cm ²
An example of a two-stage compression circuit under the condition of abs (1 evaporation) is shown. Here, the case where the difference between the condensation temperature and the evaporation temperature is relatively large is considered to indicate the case where the compression ratio is 0.6 or more.

In FIG. 3, 51a is a hot water supply heat exchanger, and 51c.
Is a heat storage heat exchanger, 51a is a condenser, and 51c
Acts as an evaporator, the temperature of the water rises due to the heat radiation of 51a, and the water becomes ice due to the heat absorption of 51c.

The difference between the condensation temperature and the evaporation temperature is relatively large,
In the case of high-temperature hot-water supply operation with a relatively large compression ratio or simultaneous hot-water supply / ice heat storage operation, the first and second compressors are operated in series and the discharge of the second (low-stage side) compressor is performed. By performing the two-stage compression operation in which the gas is sucked into the first (higher-stage side) compressor through the compressor communication pipe, two saturation temperatures can be obtained in a highly efficient operation suitable for a high compression ratio.

Next, with reference to the explanatory view showing the operating state of the multi-temperature generation circuit of this embodiment in FIG. 4, at the time of generating three temperatures for generating two condensation temperatures and one evaporation temperature, the condensation temperature and the evaporation The operation under the condition that the temperature difference is relatively small, that is, the compression ratio is relatively small will be described. This operation mode is applied, for example, during normal heating + relatively low hot water supply operation.

In FIG. 4, the heat exchanger 51a is the first condenser,
An example in which the heat exchanger 51b operates as the second condenser and the heat exchanger 51c operates as the evaporator is shown, and the third opening / closing valve 23, the fourth
Open / close valve 24, fifth open / close valve 25, open / close valves 27a, 28a,
26b, 28b, 26c and 27c are in a closed state (filled in the figure). The arrow indicates the flow of the refrigerant.

The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 flows into the first high-pressure gas pipe 61, passes through the on-off valve 26a, flows into the heat exchanger 51a which is the first condenser, and is condensed and liquefied. To be done. This liquid refrigerant flows into the liquid pipe 64 through the electric expansion valve 31a. On the other hand, the high-temperature high-pressure refrigerant gas discharged from the second compressor 2 flows into the second high-pressure gas pipe 62 through the first opening / closing valve 21, passes through the opening / closing valve 27b, and is the second condenser heat exchanger 51b. And is condensed and liquefied. The liquid refrigerant flows into the liquid pipe 64 through the electric expansion valve 31b and merges with the liquid refrigerant from the heat exchanger 51a which is the first condenser. The combined liquid refrigerant is used as an electric expansion valve 31c.
Through it to a low-pressure two-phase state, which flows into the heat exchanger 51c and is vaporized and gasified. This gas refrigerant is a low pressure gas pipe 6
After passing through 3, the first accumulator 11 is sucked into the first compressor 1 and the second compressor 2. Thus, in this operation mode, the heat exchanger 51a obtains the first condensation temperature, the heat exchanger 51b obtains the second condensation temperature, and the heat exchanger 51c obtains the evaporation temperature.

At the time of heating + hot water supply (2 condensation + 1 evaporation) in FIG. 4, normally, discharge pressure 1 (heating) 16 to 21 kg / cm ² a
bs, discharge pressure 2 (hot water supply) 21 Kg / cm ^{2 for} 2 condensation, and suction pressure 4-5 Kg / cm ² abs for 1 evaporation.

Here, 51a is a heat exchanger for hot water supply, and 51b.
Is an indoor unit heat exchanger, 51c is an outdoor unit heat exchanger, 51a and 51b are condensers, 51a is hot water supply, 5
1b works for heating. 51c acts as an evaporator. Here, the first compressor 1 is for hot water supply, and the second compressor 2 is for heating, and they are operated in parallel.

The difference between the condensation temperature and the evaporation temperature is relatively small,
In the case of simultaneous heating and hot water supply operation with a relatively small compression ratio, the first and second compressors, for example, two compressors are operated in parallel and the condensing temperature of each compressor is changed to One condensation temperature and one evaporation temperature are efficiently obtained. Moreover, it is possible to freely select a combination with the heat exchanger corresponding to each of the two compressors.

Next, with reference to the explanatory view showing the operating state of the multi-temperature generation circuit of this embodiment in FIG. 5, at the time of generating three temperatures for generating two condensation temperatures and one evaporation temperature, the condensation temperature and the evaporation The operation under the condition that the temperature difference is relatively large, that is, the condition that the compression ratio is relatively large will be described. This operation mode is applied, for example, during normal heating + relatively high hot water supply operation.

In FIG. 5, the heat exchanger 51a is the first condenser,
The example in which the heat exchanger 51b operates as the second condenser and the heat exchanger 51c operates as the evaporator is shown, and the third opening / closing valve 23, the fifth
Open / close valve 25, open / close valves 27a, 28a, 26b, 28b,
26c and 27c are in a closed state (filled in the figure). The arrow indicates the flow of the refrigerant.

A part of the refrigerant gas discharged from the second compressor 2 flows into the compressor communication pipe 66, is sucked into the first compressor through the fourth opening / closing valve 24 and the second opening / closing valve 22, The first high-pressure gas pipe 61 becomes a high-temperature high-pressure refrigerant gas after being compressed in two stages.
Flow into. This gas refrigerant flows through the opening / closing valve 26a into the heat exchanger 51a, which is the first condenser, and is condensed and liquefied. This liquid refrigerant passes through the electric expansion valve 31a and the liquid pipe 6
Inflow to 4. On the other hand, the rest of the refrigerant gas discharged from the second compressor 2 flows into the second high-pressure gas pipe 62 through the first opening / closing valve 21 and passes through the opening / closing valve 27b to be the second condenser heat exchanger. It flows into 51b and is condensed and liquefied. The liquid refrigerant flows into the liquid pipe 64 through the electric expansion valve 31b and merges with the liquid refrigerant from the heat exchanger 51a which is the first condenser. The combined liquid refrigerant flows through the electric expansion valve 31c into a low-pressure two-phase state, flows into the heat exchanger 51c, and is vaporized and gasified. The gas refrigerant passes through the low pressure gas pipe 63, the first accumulator 11, and is sucked into the second compressor 2. Thus, in this operation mode, the heat exchanger 51a obtains the first condensation temperature, the heat exchanger 51b obtains the second condensation temperature, and the heat exchanger 51c obtains the evaporation temperature.

Heating in FIG. 5 + hot water supply (2 condensation + 1 evaporation)
Occasionally, discharge pressure 1 (heating) 16 to 21 Kg / cm ² a
bs, discharge pressure 2 (hot water supply) 26-27 Kg / cm ² ab
s 2 condensation and suction pressure 4-5 Kg / cm ² abs
An example of a two-stage compression circuit under the condition of (1 evaporation) is shown.

The operation of the heat exchangers 51a, 51b and 51c is the same as that of FIG. 4, but the compressor is operated in series (two-stage compression), and the second compressor 2 compresses it to an intermediate pressure (heating is possible). Pressure), and further compressed to high pressure by the first compressor 1 (pressure at which hot water can be supplied).

The difference between the condensation temperature and the evaporation temperature is relatively large,
In the case of simultaneous operation of heating and high-temperature hot water with a relatively large compression ratio, the first and second compressors, for example, two compressors are simultaneously operated, and the discharge gas of the second (low-stage side) compressor is discharged. Part of the air is sucked into the first (higher stage) compressor through the compressor communication pipe,
A two-stage compressed refrigerant is used for hot water supply and the second stage is used for heating.
By using the remaining refrigerant of the discharge gas of the (low-stage side) compressor, two condensation temperatures and one evaporation temperature can be efficiently obtained in a highly efficient operation.

Next, referring to FIG. 6 which is an explanatory diagram showing the operating state of the multi-temperature generation circuit of this embodiment, at the time of generating three temperatures for generating one condensation temperature and two evaporation temperatures, the condensation temperature and evaporation The operation when the temperature difference is relatively small will be described. This operation mode is applied, for example, during cooling + ice heat storage operation.

FIG. 6 shows an example in which the heat exchanger 51a operates as a condenser, the heat exchanger 51b operates as a first evaporator, and the heat exchanger 51c operates as a second evaporator. Two
Open / close valve 22, fourth open / close valve 24, open / close valves 27a, 28a,
26b, 28b, 26c and 27c are in a closed state (filled in the figure). The arrow indicates the flow of the refrigerant.

The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 passes through the third on-off valve 23, the high-pressure gas communication pipe 65, and the discharge refrigerant gas of the second compressor 2 and the first high-pressure gas pipe 6.
At 1, they merge, pass through the on-off valve 26a, flow into the heat exchanger 51a, and are condensed and liquefied. This liquid refrigerant is used for the electric expansion valve 3
It flows through the liquid pipe 64 through 1a, and a part of it flows through the electric expansion valve 31b into a low-pressure two-phase state and flows into the heat exchanger 51b which is the first evaporator, and is vaporized and gasified. . This gas refrigerant passes through the second high-pressure gas pipe 62 and the fifth on-off valve 2
5, the second accumulator 12, the second check valve, the first
It is sucked into the compressor 1. On the other hand, the remaining liquid refrigerant flowing into the liquid pipe 64 passes through the electric expansion valve 31c into a low-pressure two-phase state, flows into the heat exchanger 51 that is the second evaporator, and is vaporized and gasified. The gas refrigerant passes through the low pressure gas pipe 63, the first accumulator 11, and is sucked into the second compressor 2. Thus, in this operation mode, the heat exchanger 51a obtains the condensation temperature, the heat exchanger 51b obtains the first evaporation temperature, and the heat exchanger 51c obtains the second evaporation temperature.

When cooling + ice heat storage (1 condensation + 2 evaporation) in FIG. 6, normally, one condensation of discharge pressure 18 Kg / cm ² abs and suction pressure 1 (cooling) 5-6 Kg / cm ² abs,
The suction pressure 2 (ice heat storage) is 3 Kg / cm ² abs, which is an example of 2 evaporations.

51a is an outdoor heat exchanger, 51b is an indoor heat exchanger, 51c is a heat storage heat exchanger, 51a acts as a condenser, 51b and 51c act as an evaporator, 51b is cooling, 51c stores ice heat. Here first
The compressor 1 is for cooling, and the second compressor 2 is for ice heat storage, and they are operated in parallel.

The difference between the condensation temperature and the evaporation temperature is relatively small,
In the case of cooling / ice heat storage simultaneous operation with a relatively small compression ratio, the first and second compressors, for example, two compressors are operated in parallel, and the evaporation temperature of each compressor is changed. One condensation temperature and two evaporation temperatures are efficiently obtained.

Next, using the explanatory diagram showing the operating state of the multi-temperature generation circuit of this embodiment in FIG. 7, the condensation temperature and the evaporation temperature are generated at the time of generating three temperatures for generating one condensation temperature and two evaporation temperatures. The operation when the temperature difference is relatively large will be described. This operation mode is applied, for example, during cooling + ice heat storage + high-temperature hot water supply operation.

FIG. 7 shows an example in which the heat exchanger 51a operates as a condenser, the heat exchanger 51b operates as a first evaporator, and the heat exchanger 51c operates as a second evaporator. 5
Open / close valve 25, open / close valves 27a, 28a, 26b, 28b,
26c and 27c are in a closed state (filled in the figure). The arrow indicates the flow of the refrigerant.

The high-temperature and high-pressure refrigerant gas discharged from the first compressor 1 flows into the first high-pressure gas pipe 61 and the on-off valve 26a.
Through which it flows into the heat exchanger 51a and is condensed and liquefied. The liquid refrigerant flows into the liquid pipe 64 through the electric expansion valve 31a, and a part of the liquid refrigerant flows through the electric expansion valve 31b into a low-pressure two-phase state, which is the heat exchanger 51b as the first evaporator. And is vaporized into gas. This gas refrigerant passes through the second high-pressure gas pipe 62, passes through the first on-off valve 21, merges with the discharge gas of the second compressor, passes through the fourth on-off valve 24, the second on-off valve 22, and passes through the first compression. Inhaled into machine 1. On the other hand, the remaining liquid refrigerant that has flowed into the liquid pipe 64 passes through the electric expansion valve 31c into a low-pressure two-phase state, flows into the heat exchanger 51c that is the second evaporator, and is vaporized and gasified. The gas refrigerant passes through the low pressure gas pipe 63, the first accumulator 11, and is sucked into the second compressor 2. Thus, in this operation mode, the heat exchanger 51a obtains the condensation temperature, the heat exchanger 51b obtains the first evaporation temperature, and the heat exchanger 51c obtains the second evaporation temperature.

As described above, in this embodiment, the above 6
It is possible to set three saturation temperatures for each heat exchanger according to one operation mode and functions required for each heat exchanger such as cooling and heating, hot water supply, and ice storage. In addition, when the difference between the condensation temperature and the evaporation temperature is small or large, the operation of the first and second compressors can be used separately, in parallel operation, or in series operation (two-stage compression operation), resulting in high efficiency. Cycle can be realized. Further, when cooling and ice heat storage and heating and hot water supply are operated at the same time, the exhaust heat of cooling and ice heat storage can be used for heating and hot water supply, so that a more efficient cycle can be realized. Since the accumulator is provided on the suction side of the first and second compressors, the compressor can be protected,
The amount of refrigerant can be adjusted.

At the time of cooling + ice heat storage + hot water supply (1 condensation + 2 evaporation) in FIG. 7, discharge pressure (hot water supply) 21 Kg / cm ² abs
1 condensation and suction pressure 1 (cooling) 5-6 Kg / cm
² abs, suction pressure 2 (ice heat storage) 3 Kg / cm ² abs
Is an example of two-stage compression by two evaporations.

51a is a hot water supply heat exchanger, 51b is an indoor heat exchanger, and 51c is a heat storage heat exchanger. 51a acts as a condenser, and 51b and 51c act as an evaporator. Here, the compressor is in series operation (two-stage compression), the second compressor 2 compresses it to an intermediate pressure (cooling pressure), and the first compressor 1 further compresses it to a higher pressure (hot water supply pressure). .

The difference between the condensation temperature and the evaporation temperature is relatively large,
In the case of simultaneous operation of cooling, hot water supply, and ice heat storage with a relatively high compression ratio, the first and second, for example, two compressors are operated simultaneously, and the discharge of the second (low-stage side) compressor is performed. The gas is sucked into the first (higher stage side) compressor through the compressor communication pipe, the condensing temperature of the first (higher stage side) compressor is used for hot water supply, and the first (higher stage side) is used for cooling. ) The second (low-stage) compression is used for ice heat storage, using the evaporation temperature of the compressor

Example 2. FIG. 8 is a configuration diagram of a refrigerant system of a multi-temperature generation circuit according to the vapor compression refrigeration cycle of Embodiment 2 of the present invention. In the figure, 67 is a bypass pipe that connects the liquid pipe 64 and the first accumulator 11 via the sixth opening / closing valve 30d and the capillary pipe 32 that is a flow rate controller,
A heat exchanging section 71 for exchanging heat between the pipe between the capillary tube 32 of the bypass pipe 67 and the first accumulator 11 and the suction pipe of the first compressor 1 is provided.

When the difference between the condensing temperature and the evaporating temperature is relatively large when two or three temperatures are generated, when the two compressors are operated in series, the sixth opening / closing valve 30d is opened and the liquid pipe 64 is opened. A part of the liquid refrigerant inside is guided to the bypass pipe 67, is converted into a low-pressure low-temperature two-phase refrigerant by the capillary tube 32, is heat-exchanged with the suction refrigerant gas of the first compressor in the heat exchange section 71, and is then introduced into the first accumulator. . In this way, the bypass pipe 67
Since the low-temperature two-phase refrigerant flowing through the refrigerant can cool the suction refrigerant gas of the first compressor 1, which is the high-stage compressor, the discharge temperature can be prevented from rising and the operating range can be expanded. FIG. 8 shows a discharge temperature countermeasure at the time of the two-stage compression circuit. In order to prevent the discharge temperature from rising on the high stage side (first compressor) during the two-stage compression in the case of FIGS. 3, 5, and 7, Heat is exchanged so that the suction temperature of the first compressor becomes low.

In the second embodiment, the bypass pipe 6
Although the capillary tube 32 is used as the flow rate controller of No. 7, if the bypass amount under each operating condition is properly controlled by using a mechanical or electric expansion valve, and if the discharge temperature rise is more accurately prevented, the operating range is increased. Can be further expanded.

In the above embodiment, three heat exchangers 51 are used.
The case of using a, 51b, 51c has been described,
It is also possible to use four or more heat exchangers having different capacities, and one or both of the first compressor 1 and the second compressor 2 may have a variable capacity such as frequency conversion type, pole number conversion type, and unloader type. With the type compressor, the flow rate of the refrigerant at the set saturation temperature can be varied, and the required capacity of each heat exchanger can be exhibited.

Furthermore, in the above embodiment, the case where the number of compressors is two has been described, but by using three or more compressors,
It is possible to set three or more saturation temperatures, and by connecting these in parallel or in single operation or in series operation (two-stage compression operation) and using them properly, it is possible to realize a highly efficient cycle as well.

Since the multi-temperature generation circuit by the vapor compression refrigeration cycle in the first and second embodiments of the present invention is configured as described above, it has the effects described below.

One end is a discharge side of the first compressor, the other end is a first high pressure gas pipe connected to a plurality of heat exchangers via a switch, and one end is a first high pressure gas pipe connected via a first switch. 2 On the discharge side of the compressor, the other end is connected to the plurality of heat exchangers via a switch, and branched on the way to the suction side of the first compressor via a second switch. A second high-pressure gas pipe to be connected, one end of which is connected to the suction side of the second compressor and which is connected to the suction side of the first compressor through a third switch and the other end of which is connected through a switch. A low-pressure gas pipe connected to the plurality of heat exchangers, a liquid pipe connected to the plurality of heat exchangers via a refrigerant flow controller, and a discharge side of the second compressor via a fourth switch. And a suction pipe of the first compressor, and a compressor communication pipe for sending the discharge gas of the second compressor to the first compressor. Because, air conditioning and hot water, depending on the functionality required to each heat exchanger, such as ice storage, can be set greater saturation temperature from the compressor number within each heat exchanger. In addition, when the difference between the condensation temperature and the evaporation temperature is small or large, a highly efficient cycle can be realized by selectively operating the plurality of compressors. Further, when cooling or ice heat storage and heating or hot water supply are operated at the same time, exhaust heat of cooling or ice heat storage can be used for heating or hot water supply, so that energy can be effectively used.

Since a high pressure gas communication pipe is provided,
Add the discharge gas of the second compressor to the discharge gas of the first compressor,
The condensation (or evaporation) ability can be improved.

Further, since the accumulator is provided on the suction side of the compressor, it is possible to prevent the liquid from returning to the compressor at the time of starting or switching the operation modes, and protect the compressor.
The amount of refrigerant can be adjusted.

Further, the liquid pipe and the first accumulator are connected by a bypass pipe via the sixth opening / closing valve and the flow rate controller,
By providing the heat exchange section for exchanging heat between the pipe between the flow controller of the bypass pipe and the first accumulator and the suction pipe of the first compressor, the difference between the condensation temperature and the evaporation temperature is relatively small. When the two compressors are operated in series, it is possible to cool the intake refrigerant gas of the high-stage compressor to prevent its discharge temperature from rising and to expand the operating range.

By using the variable capacity compressor as the first or second compressor, the flow rate of the refrigerant at the set saturation temperature can be made variable, and the required capacity of each heat exchanger can be exhibited.

Example 3. The third embodiment of the present invention will be described below with reference to FIGS. FIG. 9 is a block diagram of a general refrigerant circuit for generating four saturation temperatures with n = 4 showing an embodiment of the present invention. 1-3 in the figure
Are the first, second and third compressors 20a to 20d,
4a to 4d are on-off valves on the suction side and the discharge side for connecting the respective compressors, and 5 is a discharge pipe 1 of the first compressor 1 at one end.
5, the first end of which the other end is connected to each of the first to fourth heat exchangers 51a to 51d via the on-off valves 26a to 26d.
One end of the gas pipe 6 is the discharge pipe 14 of the second compressor 2 or the suction pipe 18 of the first compressor 1, and the other end is the open / close valve 2
The first to fourth heat exchangers 51 a to 5 via 7 a to 27 d
The second gas pipe 7 connected to each of 1d has one end connected to the discharge pipe 13 of the third compressor 3 or the suction pipe 17 of the second compressor 2 and the other end connected to the on-off valves 28a to 28d. A third gas pipe connected to each of the first to fourth heat exchangers 51a to 51d, one end of the third gas pipe 8 to the suction pipe 16 of the third compressor 3 and the other end of the third gas pipe 8 to the on-off valves 29a to 29d. First to
It is the 4th gas pipe connected to each of the 4th heat exchangers 51a-51d. 64 is the heat exchangers 51a to 51d
Is a liquid pipe connected to each of these via the refrigerant flow control valves 31a to 31d.

Next, the operation of this circuit will be described. Four
One saturation temperature can be freely obtained, and various combinations of circuits are possible. Here, the operation of the circuit that can obtain the saturation temperatures of 3 condensation 1 evaporation and 2 condensation 2 evaporation will be described as a typical example. . FIG. 10: is explanatory drawing which shows the driving | running operation state of the circuit which can obtain 3 condensation 1 evaporation.
Here, 51a to 51c act as first to third condensers, and 51d acts as an evaporator. In the figure, it is filled when the on-off valve is closed. The arrow indicates the flow of the refrigerant. The high temperature / high pressure refrigerant gas discharged from the first compressor 1 flows into the first gas pipe 5, passes through the on-off valve 26a, flows into the heat exchanger 51a which is the first condenser, and is condensed and liquefied. This liquid refrigerant flows into the liquid pipe 64 through the refrigerant flow control valve 31a.

Similarly, the high temperature / high pressure gas refrigerant discharged from each of the second and third compressors 2 and 3 flows into the second and third gas pipes 6 and 7 through the on-off valves 4b and 4d, respectively. ,
Each of them flows through the on-off valves 27b and 28c into the heat exchangers 51b and 51c, which are the second and third condensers, and is condensed and liquefied. The liquid refrigerant condensed and liquefied in each of the heat exchangers 51b and 51c flows into the liquid pipe 64 through the refrigerant flow control valves 31b and 31c, and joins with the liquid refrigerant from the heat exchanger 51a. The liquid refrigerant joined from the three heat exchangers 51a to 51c passes through the refrigerant flow control valve 31d to be in a low-pressure two-phase state, flows into the heat exchanger 51d, and is vaporized and gasified.
This gas refrigerant passes through the fourth gas pipe 8 and is passed through the first, second and third gas pipes.
Inhaled into the compressor. Thus, in this operation mode, the heat exchanger 51a obtains the first condensing temperature, 51b the second condensing temperature, 51c the third condensing temperature, and 51d the evaporating temperature. FIG. 11 is an explanatory diagram showing a driving operation state of a circuit capable of obtaining 2 condensation / 2 evaporation. Here, 51a and 51b are first and second condensers, 51c and 51b.
d acts on the first and second evaporators. Similarly in FIG. 11, when the on-off valve is closed in the figure, it is painted out. The arrow indicates the flow of the refrigerant.

The high temperature / high pressure gas refrigerant discharged from the first compressor 1 and the high temperature / high pressure gas refrigerant discharged from the second compressor merge into the first gas pipe 5 and pass through the on-off valve 26a. Flow into the heat exchanger 51a which is the first condenser, and is condensed and liquefied. This liquid refrigerant flows into the liquid pipe 64 through the refrigerant flow control valve 31a. On the other hand, the high-temperature / high-pressure gas refrigerant discharged from the third compressor 3 flows into the third gas pipe 7, passes through the on-off valve 28b, flows into the heat exchanger 51b that is the second condenser, and is condensed and liquefied. . This liquid refrigerant is the refrigerant flow control valve 31.
It flows into the liquid pipe 64 through b and merges with the liquid refrigerant from the heat exchanger 51a. A part of the combined liquid refrigerant passes through the refrigerant flow control valve 31c to be in a low-pressure two-phase state and flows into the heat exchanger 51c which is the first evaporator to be vaporized and gasified. This gas refrigerant passes through the second gas pipe 6 and is sucked into the first and second compressors through the suction pipe 18 of the first compressor. On the other hand, the remaining liquid refrigerant passes through the refrigerant flow rate control valve 31d to be in a low-pressure two-phase state, flows into the heat exchanger 51d which is the second evaporator, and is evaporated and gasified. The gas refrigerant is drawn into the third compressor through the fourth gas pipe 8.

As described above, in this operation mode, the first condensing temperature at the heat exchanger 51a and the second condensing temperature at 51b are
A first evaporation temperature is obtained at 51c, and a second evaporation temperature is obtained at 51d. In addition, regarding the number and position of the suction side opening / closing valves 20a to 20d and the discharge side opening / closing valves 4a to 4d, and whether or not the gas pipes 5 to 7 are connected to the suction pipes 16 to 18 and the discharge pipes 13 to 15, what operation mode is selected? It depends on how you want to realize. In addition, it is possible to replace with a check valve in the realized operation mode. Further, although the number of heat exchangers connected is four in the embodiment, there is no particular problem even if the number is further increased. In addition, one saturation temperature range is
From the compressor discharge to the condenser outlet (condensation temperature) or from the evaporator inlet to the compressor suction (evaporation temperature). That is, the term "compressor discharge side-gas tube-heat exchanger-pressure reducing means" or the compressor suction side-gas tube heat exchanger-pressure reducing means is used.

Example 4. Next, regarding Example 2, FIG.
13 will be described. Fig. 12 shows the generation of three saturation temperatures, especially 2 condensation 1 evaporation temperatures (of course 1 condensation 1 evaporation is also possible)
2 is an example of a refrigerant circuit configuration diagram that can be realized without a complicated configuration. In the figure, reference numerals 1 and 2 denote first and second compressors, and one end portion of the first and second compressors 5 is connected to the first check valve 52 through the first check valve 52.
On the discharge side of the compressor 1, the other end is a first gas pipe connected to the first to third heat exchangers 51a to 51c via the on-off valves 26a to 26d, and one end of the 6 is the second compression pipe. On the discharge side of the machine 2, the other end is connected to the first to the third through the opening / closing valves 27a to 27c.
Second gas pipe connected to the heat exchangers 51a to 51c of
Has one end on the suction side of the accumulator 56 and the other end via the on-off valves 28a to 28c to the first to third heat exchangers 51a.
To 51c, a third gas pipe, and 64 is a liquid pipe connected to each of the first to third heat exchangers 51a to 51c via refrigerant flow control valves 31a to 31c. Further, the discharge side of the accumulator 56 and the suction sides of the first and second compressors 1 and 2 are connected to the second and third check valves 5 respectively.
4, 55, and the second gas pipe 6 and the pipe of the first gas pipe 5 on the outlet side of the first check valve 52.
And are communicated with each other via the first opening / closing valve 53. In this embodiment, the number of accumulators is one, and one evaporation operation is a principle, and in the case of two evaporations, each compressor may be provided with an accumulator. Next, the operation of this circuit will be described. FIG. 13 is an explanatory diagram showing a driving operation state of a circuit capable of obtaining 2 condensation 1 evaporation temperatures. Here, 51a and 51b act as first and second condensers, and 51c acts as an evaporator. In the figure, it is filled when the on-off valve is closed. The arrow indicates the flow of the refrigerant.

The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 flows into the first gas pipe 5 through the first check valve 52, passes through the open / close valve 26a, and is the first condenser heat exchange. Bowl 5
It flows into 1a and is condensed and liquefied. This liquid refrigerant flows into the liquid pipe 64 through the refrigerant flow control valve 31a. Meanwhile, the second
The high-temperature high-pressure refrigerant gas discharged from the compressor 2 flows into the second gas pipe 6, passes through the on-off valve 27b, flows into the heat exchanger 51b that is the second condenser, and is condensed and liquefied. This liquid refrigerant flows into the liquid pipe 64 through the refrigerant flow control valve 31b,
It joins with the liquid refrigerant from the heat exchanger 51a which is the first condenser. The combined liquid refrigerant flows into the heat exchanger 51c through the refrigerant flow control valve 31c in a low-pressure two-phase state.
Evaporative gasification. This gas refrigerant passes through the third gas pipe 7 and the accumulator 56, and then passes through the first compressor 1 and the second compressor 1.
It is sucked into the compressor 2. As described above, in this operation mode, the first condensing temperature in the heat exchanger 51a is
The second condensation temperature is obtained at b, and the evaporation temperature is obtained at the heat exchanger 51c. Here, the first on-off valve 53 is used to switch the operation between the 2 condensation and the 1 condensation. (In the case of one condensation, the open state) In addition, the load of the first check valve 52 is reduced in one condensation operation, and when the first compressor 1 is stopped, the first check valve 52 moves from the second compressor 2 to the first compressor 1. This is to prevent the inflow of refrigerant. The second and third check valves 54 and 55 are provided to prevent the leakage of the refrigerant from the discharge to the suction when the first and second compressors 1 and 2 are stopped.

Example 5. Next, FIG. 14 to FIG.
It will be described with reference to FIG. Figure 14 shows 2 condensation 1 evaporation 3
It is an example of a block diagram of a refrigerant circuit intended for use in a hot water supply heat pump of a temperature generation circuit. In the figure, the basic configuration is the same as that of the fourth embodiment, and only different points will be described. Gas pipe 5
~ 7, the heat exchanger connected to the liquid pipe 64, 57 is a hot water supply heat exchanger, 58 is a bath water reheating heat exchanger, 59 is an indoor heat exchanger, 60 is an outdoor heat exchanger is there.

The first gas pipe 5 is provided with open / close valves 26a, 26b, 2
Heat exchanger 57 for hot water supply and heat exchanger 5 for additional heating via 6d
8. Connected to the outdoor heat exchanger 60. Second gas pipe 6
Is connected to the indoor heat exchanger 59 and the outdoor heat exchanger 60 via the on-off valves 27c and 27d. Next, the operation will be described. 15 to 24 are explanatory views showing main driving operation states. In the figure, when the on-off valve is closed, it is filled. The arrow indicates the flow of the refrigerant.

FIG. 15 is an explanatory diagram showing the operating state during the cooling operation. In the figure, the high-temperature high-pressure refrigerant gas discharged from the first compressor 1 passes through the first check valve 22 and the first on-off valve 23, and the high-temperature high-pressure refrigerant gas discharged from the second compressor 2 through the second gas pipe 6. It merges with the high-pressure refrigerant gas, flows into the outdoor heat exchanger 60 through the on-off valve 27d, and is condensed and liquefied. This liquid refrigerant flows into the liquid pipe 64 through the refrigerant flow control valve 31d,
After passing through the refrigerant flow control valve 31c, a low-pressure two-phase state flows into the indoor heat exchanger 59, where it is vaporized and gasified. This gas refrigerant is drawn into the first compressor 1 and the second compressor 2 through the third gas pipe 7 and the accumulator 56. Thus, in this operation mode, the outdoor heat exchanger 60 obtains the condensation temperature and the indoor heat exchanger 59 obtains the evaporation temperature. Next, the operating state during the heating operation will be described based on FIG.

The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 passes through the first check valve 52 and the first on-off valve 53, and the high-temperature refrigerant discharged from the second compressor 2 through the second gas pipe 6. The indoor heat exchanger 59 merges with the high-pressure refrigerant gas and passes through the on-off valve 27c.
And is condensed and liquefied. This liquid refrigerant flows into the liquid pipe 64 through the refrigerant flow rate control valve 31c, passes through the refrigerant flow rate control valve 31d, and becomes a low-pressure two-phase state.
It flows into 0 and is vaporized and gasified. This gas refrigerant is
It is sucked into the first compressor 1 and the second compressor 2 through the gas pipe 7 and the accumulator 56. Thus, in this operation mode, the indoor heat exchanger 59 obtains the condensation temperature and the outdoor heat exchanger 60 obtains the evaporation temperature. Next, the operating state during the hot water supply operation will be described based on FIG. The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 flows into the first gas pipe 5 via the first check valve 52, flows into the hot water heat exchanger 57 through the opening / closing valve 26a, and water Is heated to be condensed and liquefied. This liquid refrigerant flows into the liquid pipe 64 through the refrigerant flow rate control valve 31a, flows into the outdoor heat exchanger 60 in a low-pressure two-phase state through the refrigerant flow rate control valve 31d, and is vaporized and gasified. . This gas refrigerant is drawn into the first compressor 1 through the third gas pipe 7 and the accumulator 56.
Thus, in this operation mode, the hot water supply heat exchanger 57 is
To obtain the condensation temperature, and the outdoor heat exchanger 60 to obtain the evaporation temperature.

Next, the operating state during the cooling hot water supply operation will be described with reference to FIG. The high-temperature high-pressure refrigerant gas discharged from the second compressor 2 passes through the first check valve 52 and the first on-off valve 53, and the high-temperature high-pressure refrigerant gas discharged from the first compressor 1 through the first gas pipe 5. And flows into the hot water supply heat exchanger 57 through the on-off valve 26a and is condensed and liquefied. The liquid refrigerant flows into the liquid pipe 64 through the refrigerant flow rate control valve 31a, enters the indoor heat exchanger 59 in a low-pressure two-phase state through the refrigerant flow rate control valve 31c, and is vaporized and gasified. . The gas refrigerant passes through the third gas pipe 7 and the accumulator 5
It is sucked into the first compressor 1 and the second compressor 2 via 6. Thus, in this operation mode, the condensing temperature is obtained by the hot water supply heat exchanger 57 and the evaporation temperature is obtained by the indoor heat exchanger 59. Also, since it is hot water supply operation while cooling,
In the summer, the load of hot water supply is small, and the load can be covered only by the hot water supply during cooling operation. Therefore, the electricity charge for hot water supply is almost unnecessary because it is included in cooling. Next, the operating state during the heating / hot water supply operation will be described with reference to FIG. The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 flows into the first gas pipe 5, passes through the on-off valve 26a, flows into the hot water supply heat exchanger 57, and is condensed and liquefied. The liquid refrigerant flows into the liquid pipe 64 through the refrigerant flow control valve 31a. On the other hand, the high-temperature high-pressure refrigerant gas discharged from the second compressor 2 flows into the second gas pipe 6, passes through the on-off valve 27c, and the indoor heat exchanger 5
9 and is condensed and liquefied. The liquid refrigerant flows into the liquid pipe 64 through the refrigerant flow rate control valve 31c and merges with the liquid refrigerant from the hot water supply heat exchanger 57. The combined liquid refrigerant flows into the outdoor heat exchanger 60 in a low-pressure two-phase state through the refrigerant flow control valve 31d, and is vaporized and gasified. The gas refrigerant passes through the third gas pipe 7 and the accumulator 5
It is sucked into the first compressor 1 and the second compressor 2 via 6. Thus, in this operation mode, the hot water supply heat exchanger 57 obtains the first condensation temperature, the indoor heat exchanger 59 obtains the second condensation temperature, and the outdoor heat exchanger 60 obtains the evaporation temperature. As described above, by properly using the two compressors, it is possible to generate a condensation temperature suitable for both heating and hot water supply, so that hot water supply operation can be realized without lowering the heating capacity.

Next, the operating state during the additional heating operation will be described with reference to FIG. The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 flows into the first gas pipe 5 via the first check valve 52, flows into the reheating heat exchanger 58 through the on-off valve 26b, Condensed and liquefied. This liquid refrigerant flows into the liquid pipe 64 through the refrigerant flow rate control valve 31b, enters the outdoor heat exchanger 60 in a low pressure two-phase state through the refrigerant flow rate control valve 31d, and is vaporized and gasified. . This gas refrigerant is
First through the accumulator 56 through the third gas pipe 7.
It is sucked into the compressor 1. Thus, in this operation mode, the condensing temperature is obtained by the reheating heat exchanger 58 and the evaporation temperature is obtained by the outdoor heat exchanger 60. As described above, the hot water in the bathtub can be warmed by the heat pump operation.

Next, the operating state during the hot water heating rapid reheating operation will be described with reference to FIG. First compressor 1
The high-temperature high-pressure refrigerant gas discharged from the above flows into the first gas pipe 5 through the first check valve 52, passes through the on-off valve 26b, flows into the reheating heat exchanger 58, and is condensed and liquefied. This liquid refrigerant flows through the refrigerant flow control valve 31b into the liquid pipe 64, passes through the refrigerant flow control valve 31a into a low-pressure two-phase state, flows into the hot water supply heat exchanger 57, and is vaporized and gasified. It
This gas refrigerant is drawn into the first compressor 1 through the third gas pipe 7 and the accumulator 56. in this way,
In this operation mode, the condensing temperature is obtained by the reheating heat exchanger 58 and the evaporation temperature is obtained by the hot water supply heat exchanger 57. As described above, since high-temperature heat is used as a heat source, the capacity is greatly improved as compared with the outside air heat source, and the hot water in the bathtub can be warmed rapidly.

Next, the operating state during the heating / heating operation will be described with reference to FIG. The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 flows into the first gas pipe 5, passes through the on-off valve 26b, flows into the reheating heat exchanger 58, and is condensed and liquefied. This liquid refrigerant flows into the liquid pipe 64 through the refrigerant flow control valve 31b. On the other hand, the high-temperature high-pressure refrigerant gas discharged from the second compressor 2 flows into the second gas pipe 6,
It flows into the indoor heat exchanger 59 through the on-off valve 27c and is condensed and liquefied. The liquid refrigerant flows into the liquid pipe 64 through the refrigerant flow control valve 31c, and merges with the liquid refrigerant from the reheating heat exchanger 59. The combined liquid refrigerant flows into the outdoor heat exchanger 60 in a low-pressure two-phase state through the refrigerant flow control valve 31d, and is vaporized and gasified. This gas refrigerant is drawn into the first compressor 1 and the second compressor 2 through the third gas pipe 7 and the accumulator 56. As described above, in this operation mode, the first condensing temperature is obtained by the reheating heat exchanger 58, the second condensing temperature is obtained by the indoor heat exchanger 59, and the evaporation temperature is obtained by the outdoor heat exchanger 60. Similar to the heating and hot water supply operation, the reheating operation can be realized without lowering the heating capacity.

Next, the operating state during the hot water supply operation for recovering heat of the residual hot water in the bathtub will be described with reference to FIG. First
The high-temperature high-pressure refrigerant gas discharged from the compressor 1 flows into the first gas pipe 5 through the first check valve 52, flows into the hot water heat exchanger 57 through the opening / closing valve 26a, and is condensed and liquefied. It
The liquid refrigerant passes through the refrigerant flow control valve 31a and the liquid pipe 64
Into a low-pressure two-phase state through the refrigerant flow control valve 31b, and then into the reheating heat exchanger 58, where it is vaporized and gasified. This gas refrigerant is drawn into the first compressor 1 through the third gas pipe 7 and the accumulator 56. As described above, in this operation mode, the condensing temperature is obtained by the hot water supply heat exchanger 57, and the evaporation temperature is obtained by the additional heating heat exchanger 58. As described above, the heat of the waste hot water that is wasted can be effectively used for hot water supply, so that energy saving can be realized compared to hot water supply by the outside air heat source.

Finally, the operating state during the defrost heating operation using hot water supply will be described with reference to FIG. The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 flows into the first gas pipe 5, passes through the open / close valve 26d and flows into the outdoor heat exchanger 60, is condensed and liquefied, and melts frost by the heat. The liquid refrigerant flows into the liquid pipe 64 through the refrigerant flow control valve 26d. On the other hand, the high-temperature high-pressure refrigerant gas discharged from the second compressor 2 flows into the second gas pipe 6, passes through the on-off valve 27c, flows into the indoor heat exchanger 59, and is condensed and liquefied. The liquid refrigerant flows into the liquid pipe 64 through the refrigerant flow control valve 31c and merges with the liquid refrigerant from the outdoor heat exchanger 60. The combined liquid refrigerant flows through the refrigerant flow control valve 31a into a low-pressure two-phase state, flows into the heat exchanger 57, and is vaporized and gasified. This gas refrigerant is drawn into the first compressor 1 and the second compressor 2 through the third gas pipe 7 and the accumulator 56. Thus, in this operation mode, the first condensing temperature in the outdoor heat exchanger 60 and the second condensing temperature in the indoor heat exchanger 59 are
The condensing temperature of is the evaporation temperature in the hot water supply heat exchanger 57. As described above, since the heat of the hot water supply can be used as a heat source, the defrost operation can be performed while heating, and the heating capacity is not deteriorated because optimal condensing temperatures can be generated for both heating and defrost. .

Since the multi-temperature generation circuit by the vapor compression refrigeration cycle in Embodiments 3 to 5 of the present invention is configured as described above, n heat exchangers are provided for each heat exchanger according to the desired operation mode. The saturation temperature can be set, and moreover, there is an effect that a cycle with high efficiency and a wide operating range can be realized.

Further, since the multi-temperature generation circuit is constructed as described above, there is an effect that the operation modes of 2 condensation and 1 evaporation can be realized with high efficiency. Moreover, since the multi-temperature generation circuit is configured as described above, hot water supply and reheating operation can be realized at the same time without deteriorating the heating capacity, and hot water replenishment operation in the bathtub can be performed by using the heat from the hot water supply. ,
Non-stop heating operation (heating can be performed even during defrosting) and highly efficient hot water supply operation by recovering heat from cooling exhaust heat and residual hot water in the bath are possible, so that an economical (energy saving) and comfortable living life can be provided There is.

Example 6. FIG. 25 is a configuration diagram of a refrigerant system of a vapor compression refrigeration cycle of Embodiment 6 of the present invention. In the figure, 1 is a first compressor, 2 is a second compressor, and 11 is a first compressor.
Accumulator, 12 is a second accumulator, 51a,
51b and 51c are heat exchangers. 61 is the first compressor 1
Is a first high pressure gas pipe connected to the discharge side of the second compressor, 62 is a medium pressure gas pipe connected to the discharge side of the second compressor 2 via the first on-off valve 21, and 63 is a suction side of the first compressor 1. A low pressure gas pipe connected via the first accumulator 11 and a liquid pipe 64. A second opening / closing valve 22 and a first check valve 41 are provided in a pipe between the first compressor 1 and the first accumulator 11. Reference numeral 23 denotes a third opening / closing valve provided in a pipe connecting the high pressure gas pipe 61 with the pipe between the second compressor 2 and the first opening / closing valve 21, and 24 denotes the second compressor 2 and the third opening / closing valve 23. A fourth on-off valve provided in the pipe connecting the second pipe and the pipe between the second on-off valve 22 and the first check valve 41, and 25 is the medium pressure gas pipe 62.
And a fifth pipe provided between the second accumulator 12 and the pipe.
An on-off valve, 42 is the first compressor 1 and the second accumulator 12
It is the 2nd check valve provided in the piping between. In the heat exchangers 51a, 51b, 51c, the high-pressure gas pipe 61, the medium-pressure gas pipe 62, and the low-pressure gas pipe 63 are connected to the open / close valves 26a, 2
7a, 28a and 26b, 27b, 28b and 26, 2
The liquid pipe 64 is connected while branching through 7c and 28c.
Are electronic expansion valves 31a, 31b, which are refrigerant flow controllers.
31c are connected to each other. Further, a first bypass passage 68 extending from the medium pressure gas pipe 62 to the liquid pipe 64 via the opening / closing valve 30a and a second bypass passage extending from the liquid pipe 64 to the suction side of the first compressor 1 via the opening / closing valve 30b. It has a path 67.

The multi-temperature generation circuit of the present invention has six operation modes as shown in Table 1, which will be described with reference to FIGS.

First, using the explanatory diagram showing the operating state of the multi-temperature generation circuit of the embodiment shown in FIG. 26, at the time of generating two temperatures for generating one condensation temperature and one evaporation temperature, the condensation temperature and the evaporation temperature The operation when the difference between is relatively small will be described. This operation mode is applied, for example, during normal cooling or heating.

FIG. 26 shows an example in which the heat exchanger 51a operates as a condenser, the heat exchanger 51b stops and the heat exchanger 51c operates as an evaporator. The first on-off valve 21 and the fourth on-off valve 2 are shown.
4, fifth on-off valve 25, on-off valves 27a, 28a, 26b,
27b, 28b, 26c, 27c, 30a, 30b are in a closed state (filled in the figure). The first compressor 1,
The second compressor 2 is operated in parallel. The arrow indicates the flow of the refrigerant.

The high-temperature high-pressure refrigerant gas discharged from the second compressor 2 passes through the high-pressure gas communication pipe 65 and the first high-pressure gas pipe 61.
At this time, the high-temperature high-pressure refrigerant gas discharged from the first compressor 1 merges, flows into the heat exchanger 51a through the on-off valve 26a, and is condensed and liquefied. The liquid refrigerant flows through the electric expansion valve 31a into the liquid pipe 64, and then flows through the electric expansion valve 31c into a low-pressure two-phase state into the heat exchanger 51c to be vaporized and gasified. The gas refrigerant passes through the low pressure gas pipe 63, the first accumulator 11, and the first compressor 1 and the second compressor 1.
It is sucked into the compressor 2. Thus, in this operation mode, the heat exchanger 51a obtains the condensation temperature and the heat exchanger 51c obtains the evaporation temperature.

Next, with reference to FIG. 27, an operation will be described in the case where the two temperatures are generated to generate one condensation temperature and one evaporation temperature and the difference between the condensation temperature and the evaporation temperature is relatively large. This operation mode is applied, for example, to hot water supply or hot water supply + ice heat storage. In FIG. 27, the heat exchanger 51a
Is a condenser, the heat exchanger 51b is stopped, and the heat exchanger 51c operates as an evaporator.
Third opening / closing valve 23, fourth opening / closing valve 24, fifth opening / closing valve 25, opening / closing valves 27a, 28a, 26b, 27b, 28b, 26
The c and 27c open / close valves are closed.

The refrigerant gas discharged from the second compressor 2 is
A first on-off valve, a medium pressure gas pipe 62, a first bypass passage 68,
The liquid enters into the liquid pipe 64 through the seventh on-off valve 30a, is cooled by being mixed with the liquid in the liquid pipe 64, and passes through the second bypass passage 67 and the eighth on-off valve 30b to reach the first compressor 1. Inhaled. The high-temperature and high-pressure gas further compressed by the first compressor 1 flows into the heat exchanger 51a through the high-pressure gas pipe 61 and the opening / closing valve 26a, and is condensed and liquefied. This liquid refrigerant passes through the electric expansion valve 31a to become a high-pressure two-phase refrigerant,
It flows into the liquid pipe 64. The liquid refrigerant in the liquid pipe is the electronic expansion valve 3
A low-pressure two-phase state is passed through 1c, flows into the heat exchanger 51c, and is vaporized and gasified. This gas refrigerant is used for the on-off valve 2
8c, the low pressure gas pipe 63, the first accumulator 11, and the second compressor 2. As described above, in this operation mode, the two-stage compression operation is performed, the discharge gas of the second compressor 2 that is the low-stage compressor is cooled, and the high-stage compression operation is performed, and the second-stage compressor that is the second-stage compression operation is performed. Since the discharge gas of the compressor 2 is cooled and sucked into the first compressor 1 that is the high-stage compressor, the discharge temperature can be prevented from rising, and the condensation temperature in the heat exchanger 51a can be reduced in a wide operating range. The evaporation temperature is obtained in the heat exchanger 51c.

Next, referring to FIG. 28, which is an explanatory diagram showing the operating state of the multi-temperature generation circuit of this embodiment, the condensation temperature and the evaporation temperature are generated at the time of generating three temperatures for generating two condensation temperatures and one evaporation temperature. The operation when the temperature difference is relatively small will be described. This operation mode is applied, for example, during normal heating + relatively low hot water supply operation.

FIG. 28 shows an example in which the heat exchanger 51a operates as a first condenser, the heat exchanger 51b operates as a second condenser, and the heat exchanger 51c operates as an evaporator. The third on-off valve 23,
Fourth on-off valve 24, fifth on-off valve 25, on-off valves 27a, 28
a, 26b, 28b, 26c, 27c, 30a, 30b
Is closed (filled in the figure). The arrow indicates the flow of the refrigerant.

The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 flows into the first high-pressure gas pipe 61, passes through the on-off valve 26a, flows into the heat exchanger 51a as the first condenser, and is condensed and liquefied. To be done. This liquid refrigerant flows into the liquid pipe 64 through the electric expansion valve 31a. On the other hand, the high-temperature high-pressure refrigerant gas discharged from the second compressor 2 flows into the second high-pressure gas pipe 62 through the first opening / closing valve 21, passes through the opening / closing valve 27b, and is the second condenser heat exchanger 51b. And is condensed and liquefied. The liquid refrigerant flows into the liquid pipe 64 through the electric expansion valve 31b and merges with the liquid refrigerant from the heat exchanger 51a which is the first condenser. The combined liquid refrigerant is used as an electric expansion valve 31c.
Through it to a low-pressure two-phase state, which flows into the heat exchanger 51c and is vaporized and gasified. This gas refrigerant is a low pressure gas pipe 6
After passing through 3, the first accumulator 11 is sucked into the first compressor 1 and the second compressor 2. Thus, in this operation mode, the heat exchanger 51a obtains the first condensation temperature, the heat exchanger 51b obtains the second condensation temperature, and the heat exchanger 51c obtains the evaporation temperature.

Next, referring to FIG. 29, two condensing temperatures and 1
The operation will be described in the case where the difference between the condensation temperature and the evaporation temperature is relatively large when three temperatures are generated to generate one evaporation temperature. This operation mode is applied, for example, during normal heating + relatively high hot water supply operation. FIG. 29 shows an example in which the heat exchanger 51a operates as a first condenser, the heat exchanger 51b operates as a second condenser, and the heat exchanger 51c operates as an evaporator.
Second on-off valve 22, third on-off valve 23, fourth on-off valve 24, fifth on-off valve 25, on-off valves 27a, 28a, 26b, 28
b, 26c, 27c open / close valves are closed.

A part of the refrigerant gas discharged from the second compressor 2 passes through the first opening / closing valve 21, the medium pressure gas pipe 62, the first bypass passage 68, and the seventh opening / closing valve 30a to the liquid pipe 64. enter,
It is cooled by mixing with the liquid in the liquid pipe 64, and the second
It is sucked into the first compressor 1 through the bypass path 67 and the eighth opening / closing valve 30b. The high-temperature and high-pressure gas further compressed by the first compressor 1 is the high-pressure gas pipe 61, the on-off valve 26.
It flows into the heat exchanger 51a through a and is condensed and liquefied.
This liquid refrigerant becomes a two-phase refrigerant through the electronic expansion valve 31a and flows into the liquid pipe 64. On the other hand, the rest of the refrigerant gas discharged from the second compressor 2 is the first on-off valve 21 and the medium pressure gas pipe 6.
2. Through the on-off valve 27b, it flows into the heat exchanger 51b which is the second condenser, and is condensed and liquefied. This liquid refrigerant flows into the liquid pipe 64 through the electronic expansion valve 31b, and joins with the two-phase refrigerant from the heat exchanger 51a which is the first condenser. Of the combined refrigerant, the gas refrigerant flows to the suction side of the first compressor 1, and the liquid refrigerant flows through the electronic expansion valve 31c into a low-pressure two-phase state and then flows into the heat exchanger 51c to evaporate gas. Be converted. This gas refrigerant passes through the low-pressure gas pipe 63 through the opening / closing valve 28c, the first accumulator 11, and the second accumulator 11.
It is sucked into the compressor 2. As described above, in this operation mode, the discharge gas of the second compressor 2 that is the low-stage compressor is cooled and sucked into the first compressor 1 that is the high-stage compressor, so that the discharge temperature rises. In the wide operating range that can be prevented, the first condensing temperature in the heat exchanger 51a is
The second condensation temperature is obtained at b, and the evaporation temperature is obtained at the heat exchanger 51c.

Next, with reference to the explanatory view showing the operating state of the multi-temperature generation circuit of this embodiment in FIG. 30, at the time of generating three temperatures for generating one condensation temperature and two evaporation temperatures, the condensation temperature and the evaporation The operation when the temperature difference is relatively small will be described. This operation mode is applied, for example, during cooling + ice heat storage operation.

FIG. 30 shows an example in which the heat exchanger 51a operates as a condenser, the heat exchanger 51b operates as a first evaporator, and the heat exchanger 51c operates as a second evaporator. 2 on-off valve 22, 4th on-off valve 24, on-off valves 27a, 28
a, 26b, 28b, 26c, 27c, 30a, 30b
Is closed (filled in the figure). The arrow indicates the flow of the refrigerant.

The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 passes through the third on-off valve 23, the high-pressure gas communication pipe 65, and the refrigerant discharged from the second compressor 2 and the first high-pressure gas pipe 6.
At 1, they merge, pass through the on-off valve 26a, flow into the heat exchanger 51a, and are condensed and liquefied. This liquid refrigerant is used for the electric expansion valve 3
It flows through the liquid pipe 64 through 1a, and a part of it flows through the electric expansion valve 31b into a low-pressure two-phase state and flows into the heat exchanger 51b which is the first evaporator, and is vaporized and gasified. . This gas refrigerant passes through the second high-pressure gas pipe 62 and the fifth on-off valve 2
5, the second accumulator 12, the second check valve, the first
It is sucked into the compressor 1. On the other hand, the remaining liquid refrigerant that has flowed into the liquid pipe 64 passes through the electric expansion valve 31c into a low-pressure two-phase state and flows into the heat exchanger 51c that is the second evaporator.
Evaporative gasification. The gas refrigerant passes through the low pressure gas pipe 63, the first accumulator 11, and is sucked into the second compressor 2. Thus, in this operation mode, the heat exchanger 51a obtains the condensation temperature, the heat exchanger 51b obtains the first evaporation temperature, and the heat exchanger 51c obtains the second evaporation temperature.

Next, referring to FIG. 31, one condensing temperature and 2
The operation will be described in the case where the difference between the condensation temperature and the evaporation temperature is relatively large when three temperatures are generated to generate one evaporation temperature. This operation mode is applied, for example, during cooling + ice heat storage + high-temperature hot water supply operation. In FIG. 31, the heat exchanger 51
a is a condenser, heat exchanger 51b is a first evaporator, heat exchanger 5
1c shows an example in which it operates as a second evaporator,
Open / close valve 23, fifth open / close valve 25, open / close valves 27a, 28a,
26b, 28b, 26c, 27c and the on-off valve 30b are closed.

The high-temperature and high-pressure refrigerant gas discharged from the first compressor 1 flows into the high-pressure gas pipe 61, passes through the on-off valve 26a, flows into the heat exchanger 51a, and is condensed and liquefied. The liquid refrigerant flows into the liquid pipe 64 through the electronic expansion valve 31a, and a part of the liquid refrigerant passes through the electronic expansion valve 31b to become a low-pressure two-phase state, which is the heat exchanger 51b which is the first evaporator. And is vaporized into gas. This gas refrigerant is used as an on-off valve 27b.
Through the seventh open / close valve 30a and the first bypass passage 68, and then merges with the liquid refrigerant bypassed, and then the intermediate pressure gas pipe 6
2 through the first on-off valve 21, merges with the discharge gas of the second compressor, passes through the fourth on-off valve 24, the second on-off valve 22,
It is sucked into the first compressor 1. On the other hand, the remaining liquid refrigerant that has flowed into the liquid pipe 64 passes through the electronic expansion valve 31c to become a low-pressure two-phase state and then flows into the heat exchanger 51c that is the second evaporator, and is vaporized and gasified. This gas refrigerant is used as an on-off valve 28c.
After passing through the low pressure gas pipe 63, the first accumulator 1
After passing through 1, the air is sucked into the second compressor 2. As described above, in this operation mode, the discharge gas of the second compressor 2 which is the low-stage side compressor is mixed with the liquid refrigerant bypassed from the liquid pipe 64 to be cooled, and therefore the high-stage side compressor The discharge temperature of the compressor 1 is prevented from rising and the condensing temperature is obtained by the heat exchanger 51a, the first evaporating temperature is obtained by the heat exchanger 51b, and the second evaporating temperature is obtained by the heat exchanger 51c in a wide operating range.

Example 7. Next, FIG. 32 is a configuration diagram of a refrigerant system of a vapor compression cycle according to a seventh embodiment of the present invention. In the figure, 33 is an electronic expansion valve.

Like the sixth embodiment, the multi-temperature generation circuit of the seventh embodiment also has six operation modes as shown in Table 1, which will be described with reference to FIGS.

First, referring to FIG. 33, which is an explanatory diagram showing the operating state of the multi-temperature generation circuit of the seventh embodiment, when two temperatures are generated to generate one condensation temperature and one evaporation temperature, The operation when the difference in evaporation temperature is relatively small will be described. This operation mode is applied, for example, during normal cooling or heating.

FIG. 33 shows an example in which the heat exchanger 51a operates as a condenser, the heat exchanger 51b stops and the heat exchanger 51c operates as an evaporator. The first on-off valve 21 and the fourth on-off valve 2 are shown.
4, fifth on-off valve 25, on-off valves 27a, 28a, 26b,
27b, 28b, 26c, 27c and 30b are closed (filled in the figure), and the refrigerant flow rate controller 33 is fully closed. The first compressor 1 and the second compressor 2 are operated in parallel. The arrow indicates the flow of the refrigerant.

The high-temperature high-pressure refrigerant gas discharged from the second compressor 2 passes through the high-pressure gas communication pipe 65 and the first high-pressure gas pipe 61.
At this time, the high-temperature high-pressure refrigerant gas discharged from the first compressor 1 merges, flows into the heat exchanger 51a through the on-off valve 26a, and is condensed and liquefied. The liquid refrigerant flows through the electric expansion valve 31a into the liquid pipe 64, and then flows through the electric expansion valve 31c into a low-pressure two-phase state into the heat exchanger 51c to be vaporized and gasified. The gas refrigerant passes through the low pressure gas pipe 63, the first accumulator 11, and the first compressor 1 and the second compressor 1.
It is sucked into the compressor 2. Thus, in this operation mode, the heat exchanger 51a obtains the condensation temperature and the heat exchanger 51c obtains the evaporation temperature.

Next, referring to FIG. 34, which is an explanatory view showing the operating state of the multi-temperature generation circuit of this embodiment, at the time of generating two temperatures, one condensation temperature and one evaporation temperature, The operation when the difference between the evaporation temperature and the evaporation temperature is relatively large will be described. This operation mode is applied, for example, to hot water supply or hot water supply + ice heat storage.

FIG. 34 shows an example in which the heat exchanger 51a operates as a condenser, the heat exchanger 51b stops, and the heat exchanger 51c operates as an evaporator. The first on-off valve 21 and the third on-off valve 2 are shown.
3, fifth on-off valve 25, on-off valves 27a, 28a, 26b,
27b, 28b, 26c, 27c and 30b are closed (filled in the figure), and the refrigerant flow rate controller 33 is fully closed. The first compressor 1 and the second compressor 2 are operated in series. The arrow indicates the flow of the refrigerant.

The refrigerant gas discharged from the second compressor 2 is
High-pressure gas communication pipe 65 and compressor communication pipe 6 branched from this
5, it is sucked into the first compressor 1 through the fourth opening / closing valve 24 and the second opening / closing valve 22, is compressed in two stages, and becomes high-temperature high-pressure refrigerant gas, which then flows into the first high-pressure gas pipe 61. The liquid refrigerant flows through the electric expansion valve 31a into the liquid pipe 64, and then flows through the electric expansion valve 31c into a low-pressure two-phase state into the heat exchanger 51c to be vaporized and gasified. The gas refrigerant passes through the low pressure gas pipe 63, the first accumulator 11, and is sucked into the second compressor 2. in this way,
In this operation mode, the two-stage compression operation is performed and the heat exchanger 5
The condensation temperature is obtained at 1a, and the evaporation temperature is obtained at the heat exchanger 51c.

Next, referring to FIG. 35, which is an explanatory view showing the operating state of the multi-temperature generation circuit of this embodiment, the condensation temperature and the condensation temperature are The operation when the difference in evaporation temperature is relatively small will be described. This operation mode is applied, for example, during normal heating + relatively low hot water supply operation.

FIG. 35 shows an example in which the heat exchanger 51a operates as a first condenser, the heat exchanger 51b operates as a second condenser, and the heat exchanger 51c operates as an evaporator. The third on-off valve 23,
Fourth on-off valve 24, fifth on-off valve 25, on-off valves 27a, 28
a, 26b, 28b, 26c, 27c, 30b are closed (filled in the figure), and the refrigerant flow rate controller 33 is fully closed. The arrow indicates the flow of the refrigerant.

The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 flows into the first high-pressure gas pipe 61, passes through the on-off valve 26a, flows into the heat exchanger 51a as the first condenser, and is condensed and liquefied. To be done. This liquid refrigerant flows into the liquid pipe 64 through the electric expansion valve 31a. On the other hand, the high-temperature high-pressure refrigerant gas discharged from the second compressor 2 flows into the second high-pressure gas pipe 62 through the first opening / closing valve 21, passes through the opening / closing valve 27b, and is the second condenser heat exchanger 51b. And is condensed and liquefied. The liquid refrigerant flows into the liquid pipe 64 through the electric expansion valve 31b and merges with the liquid refrigerant from the heat exchanger 51a which is the first condenser. The combined liquid refrigerant is used as an electric expansion valve 31c.
Through it to a low-pressure two-phase state, which flows into the heat exchanger 51c and is vaporized and gasified. This gas refrigerant is a low pressure gas pipe 6
After passing through 3, the first accumulator 11 is sucked into the first compressor 1 and the second compressor 2. Thus, in this operation mode, the heat exchanger 51a obtains the first condensation temperature, the heat exchanger 51b obtains the second condensation temperature, and the heat exchanger 51c obtains the evaporation temperature.

First, with reference to FIG. 36, an operation will be described in the case where the three temperatures are generated to generate two condensation temperatures and one evaporation temperature, and the difference between the condensation temperature and the evaporation temperature is relatively large. This operation mode is applied, for example, during normal heating + relatively high hot water supply operation. In FIG. 36, the heat exchanger 51a is the first condenser, the heat exchanger 51b is the second condenser,
The example in which the heat exchanger 51c operates as an evaporator is shown, and the second opening / closing valve 22, the third opening / closing valve 23, and the fourth opening / closing valve 2 are shown.
4, fifth on-off valve 25, on-off valves 27a, 28a, 26b,
28b, 26c and 27c are closed.

A part of the refrigerant gas discharged from the second compressor 2 enters the liquid pipe 64 through the first opening / closing valve 21, the medium pressure gas pipe 62, and the refrigerant flow rate controller 33, and then enters the liquid pipe 64. It is cooled by being mixed with the liquid, and is sucked into the first compressor 1 through the eighth opening / closing valve 30b. The high-temperature and high-pressure gas further compressed by the first compressor 1 flows into the heat exchanger 51a through the high-pressure gas pipe 61 and the opening / closing valve 26a, and is condensed and liquefied. This liquid refrigerant becomes a two-phase refrigerant by the electronic expansion valve 31a and flows into the liquid pipe 64. On the other hand, the second compressor 2
The rest of the refrigerant gas discharged from the gas passes through the first opening / closing valve 21, the intermediate pressure gas pipe 62, and the opening / closing valve 27b, flows into the heat exchanger 51b as the second condenser, and is condensed and liquefied. This liquid refrigerant flows into the liquid pipe 64 through the electronic expansion valve 31b, and joins with the two-phase refrigerant from the heat exchanger 51a which is the first condenser. Of the combined refrigerant, the gas refrigerant is the first compressor 1
Of the liquid refrigerant passes through the electronic expansion valve 31c into a low-pressure two-phase state, flows into the heat exchanger 51c, and is vaporized and gasified. The gas refrigerant passes through the low pressure gas pipe 63 through the opening / closing valve 28c, passes through the first accumulator 11, and is sucked into the second compressor 2. As described above, in this operation mode, the refrigerant flow rate controller 33 controls the amount of the refrigerant bypassed from the second compressor, which is the low-stage compressor, to the intake side of the high-stage compressor, so that the heat exchangers 51a, 51b
Of the heat exchanger 51a, the discharge temperature rise is prevented, and the first condensing temperature of the heat exchanger 51a is
The second condensation temperature is obtained at b, and the evaporation temperature is obtained at the heat exchanger 51c.

Next, using the explanatory diagram showing the operating state of the multi-temperature generation circuit of this embodiment in FIG. 37, at the time of generating three temperatures, one condensation temperature and two evaporation temperatures are generated, the condensation temperature and evaporation The operation when the temperature difference is relatively small will be described. This operation mode is applied, for example, during normal cooling + ice heat storage operation.

FIG. 37 shows an example in which the heat exchanger 51a operates as a condenser, the heat exchanger 51b operates as a first evaporator, and the heat exchanger 51c operates as a second evaporator. 2 on-off valve 22, 4th on-off valve 24, on-off valves 27a, 28
a, 26b, 28b, 26c, 27c, 30b are closed (filled in the figure), and the refrigerant flow rate controller 33 is fully closed. The arrow indicates the flow of the refrigerant.

The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 passes through the third on-off valve 23, the high-pressure gas communication pipe 65, and the refrigerant discharged from the second compressor 2 and the first high-pressure gas pipe 6.
At 1, they merge, pass through the on-off valve 26a, flow into the heat exchanger 51a, and are condensed and liquefied. This liquid refrigerant is used for the electric expansion valve 3
It flows through the liquid pipe 64 through 1a, and a part of it flows through the electric expansion valve 31b into a low-pressure two-phase state and flows into the heat exchanger 51b which is the first evaporator, and is vaporized and gasified. . This gas refrigerant passes through the second high-pressure gas pipe 62 and the fifth on-off valve 2
5, the second accumulator 12, the second check valve, the first
It is sucked into the compressor 1. On the other hand, the remaining liquid refrigerant that has flowed into the liquid pipe 64 passes through the electric expansion valve 31c into a low-pressure two-phase state and flows into the heat exchanger 51c that is the second evaporator.
Evaporative gasification. The gas refrigerant passes through the low pressure gas pipe 63, the first accumulator 11, and is sucked into the second compressor 2. Thus, in this operation mode, the heat exchanger 51a obtains the condensation temperature, the heat exchanger 51b obtains the first evaporation temperature, and the heat exchanger 51c obtains the second evaporation temperature.

Next, referring to FIG. 38, one condensation temperature and 2
The operation will be described in the case where the difference between the condensation temperature and the evaporation temperature is relatively large when three temperatures are generated to generate one evaporation temperature. This operation mode is applied, for example, during cooling + ice heat storage + high-temperature hot water supply operation. In FIG. 38, the heat exchanger 51
a is a condenser, heat exchanger 51b is a first evaporator, heat exchanger 5
1c shows an example in which it operates as a second evaporator,
Open / close valve 23, fifth open / close valve 25, open / close valves 27a, 28a,
26b, 28b, 26c, 27c and the on-off valve 30b are closed.

The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 flows into the high-pressure gas pipe 61, passes through the on-off valve 26a, flows into the heat exchanger 51a, and is condensed and liquefied. The liquid refrigerant flows into the liquid pipe 64 through the electronic expansion valve 31a, and a part of the liquid refrigerant passes through the electronic expansion valve 31b to become a low-pressure two-phase state, which is the heat exchanger 51b which is the first evaporator. And is vaporized into gas. This gas refrigerant is used as an on-off valve 27b.
Through the refrigerant flow rate controller 33 and then merges with the liquid refrigerant, then passes through the medium-pressure gas pipe 62, passes through the first on-off valve 21, and merges with the discharge gas of the second compressor, It is sucked into the first compressor 1 via the on-off valve 24 and the second on-off valve 22. On the other hand, the remaining liquid refrigerant that has flowed into the liquid pipe 64 passes through the electronic expansion valve 31c to become a low-pressure two-phase state and then flows into the heat exchanger 51c that is the second evaporator, and is vaporized and gasified. The gas refrigerant passes through the on-off valve 28c, the low-pressure gas pipe 63, the first accumulator 11, and is sucked into the second compressor 2. Thus, in this operating mode,
An appropriate amount of the liquid refrigerant controlled by the refrigerant flow controller 33 is mixed with the discharge gas of the second compressor 2 that is the low-stage compressor,
By using saturated gas as the suction of the first compressor 1 which is the high-stage compressor, the two-stage compression operation is efficiently performed while preventing the discharge temperature from increasing without performing liquid compression.
At the heat exchanger 51b, the first evaporation temperature is obtained at the heat exchanger 51b, and the second evaporation temperature is obtained at the heat exchanger 51c.

Example 8. FIG. 39 is a block diagram of the refrigerant system of the vapor compression cycle of the eighth embodiment of the present invention. In the figure, 69 is a liquid receiver. The multi-temperature generation circuit according to the eighth embodiment also has six operation modes as shown in Table 1, which will be described with reference to FIGS.

First, referring to FIG. 40, which is an explanatory view showing the operating state of the multi-temperature generation circuit according to the eighth embodiment, the condensation temperature and the condensation temperature are The operation when the difference in evaporation temperature is relatively small will be described. This operation mode is applied, for example, during normal cooling or heating.

FIG. 40 shows an example in which the heat exchanger 51a operates as a condenser, the heat exchanger 51b stops and the heat exchanger 51c operates as an evaporator. The first on-off valve 21 and the fourth on-off valve 2 are shown.
4, fifth on-off valve 25, on-off valves 27a, 28a, 26b,
27b, 28b, 26c, 27c, 30a, 30b are in a closed state (filled in the figure). The first compressor 1,
The second compressor 2 is operated in parallel. The arrow indicates the flow of the refrigerant.

The high-temperature high-pressure refrigerant gas discharged from the second compressor 2 passes through the high-pressure gas communication pipe 65 and the first high-pressure gas pipe 61.
At this time, the high-temperature high-pressure refrigerant gas discharged from the first compressor 1 merges, flows into the heat exchanger 51a through the on-off valve 26a, and is condensed and liquefied. The liquid refrigerant flows through the electric expansion valve 31a into the liquid pipe 64, and then flows through the electric expansion valve 31c into a low-pressure two-phase state into the heat exchanger 51c to be vaporized and gasified. The gas refrigerant passes through the low pressure gas pipe 63, the first accumulator 11, and the first compressor 1 and the second compressor 1.
It is sucked into the compressor 2. Thus, in this operation mode, the heat exchanger 51a obtains the condensation temperature and the heat exchanger 51c obtains the evaporation temperature.

Next, with reference to FIG. 41, an operation will be described in which two condensation temperatures, one condensation temperature and one evaporation temperature, are generated and the difference between the condensation temperature and the evaporation temperature is relatively large. This operation mode is applied, for example, to hot water supply or hot water supply + ice heat storage. In FIG. 41, the heat exchanger 51a
Is a condenser, the heat exchanger 51b is stopped, and the heat exchanger 51c operates as an evaporator.
Third opening / closing valve 23, fourth opening / closing valve 24, fifth opening / closing valve 25, opening / closing valves 27a, 28a, 26b, 27b, 28b, 26
c and 27c are closed.

The refrigerant gas discharged from the second compressor 2 is
The liquid enters the liquid receiver 68 through the first opening / closing valve 21, the medium pressure gas pipe 62, the bypass passage 66, and the seventh opening / closing valve 30a, and is cooled by being mixed with the liquid in the liquid receiver 68,
It is sucked into the first compressor 1 through the bypass 67 and the eighth opening / closing valve 30b. The high-temperature and high-pressure gas further compressed by the first compressor 1 flows into the heat exchanger 51a through the high-pressure gas pipe 61 and the opening / closing valve 26a, and is condensed and liquefied. The liquid refrigerant becomes a high-pressure two-phase refrigerant through the electronic expansion valve 31a and flows into the liquid receiver 68. The liquid refrigerant in the liquid receiver 69 passes through the seventh on-off valve 30a to become a low-pressure two-phase state, flows into the heat exchanger 51c, and is vaporized and gasified. The gas refrigerant passes through the open / close valve 28c, passes through the low pressure gas pipe 63, passes through the first accumulator 11, and is sucked into the second compressor 2. As described above, in this operation mode, the two-stage compression operation is performed, and the liquid receiver 69 causes the heat exchanger 51a to operate.
The performance of gas-liquid separation of the two-phase refrigerant flowing from the side is improved,
First compressor 1 which is a high-stage compressor as a completely saturated gas
The heat exchanger 51a efficiently obtains the condensation temperature and the heat exchanger 51c efficiently obtains the evaporation temperature while preventing the discharge temperature from rising. Further, it becomes possible to accumulate the amount of surplus refrigerant in various operation modes.

Next, referring to FIG. 42, which is an explanatory view showing the operating state of the multi-temperature generation circuit of this embodiment, the condensation temperature and the evaporation temperature are generated at the time of generating three temperatures for generating two condensation temperatures and one evaporation temperature. The operation when the temperature difference is relatively small will be described. This operation mode is applied, for example, during normal heating + relatively low hot water supply operation.

FIG. 42 shows an example in which the heat exchanger 51a operates as a first condenser, the heat exchanger 51b operates as a second condenser, and the heat exchanger 51c operates as an evaporator. The third on-off valve 23,
Fourth on-off valve 24, fifth on-off valve 25, on-off valves 27a, 28
a, 26b, 28b, 26c, 27c, 30a, 30b
Is closed (filled in the figure). The arrow indicates the flow of the refrigerant.

The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 flows into the first high-pressure gas pipe 61, passes through the on-off valve 26a, flows into the heat exchanger 51a as the first condenser, and is condensed and liquefied. To be done. This liquid refrigerant flows into the liquid pipe 64 through the electric expansion valve 31a. On the other hand, the high-temperature high-pressure refrigerant gas discharged from the second compressor 2 flows into the second high-pressure gas pipe 62 through the first opening / closing valve 21, passes through the opening / closing valve 27b, and is the second condenser heat exchanger 51b. And is condensed and liquefied. The liquid refrigerant flows into the liquid pipe 64 through the electric expansion valve 31b and merges with the liquid refrigerant from the heat exchanger 51a which is the first condenser. The combined liquid refrigerant is used as an electric expansion valve 31c.
Through it to a low-pressure two-phase state, which flows into the heat exchanger 51c and is vaporized and gasified. This gas refrigerant is a low pressure gas pipe 6
After passing through 3, the first accumulator 11 is sucked into the first compressor 1 and the second compressor 2. Thus, in this operation mode, the heat exchanger 51a obtains the first condensation temperature, the heat exchanger 51b obtains the second condensation temperature, and the heat exchanger 51c obtains the evaporation temperature.

Next, referring to FIG. 43, two condensing temperatures and 1
The operation will be described in the case where the difference between the condensation temperature and the evaporation temperature is relatively large when three temperatures are generated to generate one evaporation temperature. This operation mode is applied, for example, during normal heating + relatively high hot water supply operation. FIG. 43 shows an example in which the heat exchanger 51a operates as a first condenser, the heat exchanger 51b operates as a second condenser, and the heat exchanger 51c operates as an evaporator.
Second on-off valve 22, third on-off valve 23, fourth on-off valve 24, fifth on-off valve 25, on-off valves 27a, 28a, 26b, 28
b, 26c, 27c open / close valves are closed.

A part of the refrigerant gas discharged from the second compressor 2 is part of the first opening / closing valve 21, the medium pressure gas pipe 62, and the bypass passage 6.
The liquid enters the liquid receiver 69 through the eighth and seventh open / close valves 30a, is cooled by being mixed with the liquid in the liquid receiver 69, and is sucked into the first compressor 1 through the bypass passage 67 and the eighth open / close valve 30b. It The high-temperature and high-pressure gas further compressed by the first compressor 1 is the high-pressure gas pipe 61, the on-off valve 2
It flows into the heat exchanger 51a through 6a and is condensed and liquefied. This liquid refrigerant becomes a two-phase refrigerant by the electronic expansion valve 31a and flows into the liquid pipe 64. On the other hand, the rest of the refrigerant gas discharged from the second compressor 2 passes through the first opening / closing valve 21, the intermediate pressure gas pipe 62, and the opening / closing valve 27b, flows into the heat exchanger 51b which is the second condenser, and is condensed. Liquefied. This liquid refrigerant flows into the liquid receiver 68 through the electronic expansion valve 31b, and joins with the two-phase refrigerant from the heat exchanger 51a which is the first condenser. Of the combined refrigerant, the gas refrigerant is the first
The liquid refrigerant flows to the suction side of the compressor 1, passes through the electronic expansion valve 31, becomes a low-pressure two-phase state, flows into the heat exchanger 51c, and is vaporized and gasified. This gas refrigerant is used as an on-off valve 28c.
Through the low pressure gas pipe 63, the first accumulator 11 and the second compressor 2. in this way,
In this operation mode, the two-stage compression operation is performed, and the performance of gas-liquid separation of the two-phase refrigerant flowing in from the heat exchanger 51a side by the liquid receiver 69 is improved, and it is the high-stage side compressor that is completely saturated gas. The heat can be sucked into the compressor 1 and, at the same time, the discharge temperature can be prevented from increasing and the first condensing temperature in the heat exchanger 51a and the second condensing temperature in the heat exchanger 51b can be efficiently changed. The evaporation temperature is obtained at 51c.

Next, with reference to the explanatory view showing the operating state of the multi-temperature generation circuit of this embodiment shown in FIG. 44, at the time of generating three temperatures, one condensation temperature and two evaporation temperatures are generated, the condensation temperature and the evaporation The operation when the temperature difference is relatively small will be described. This operation mode is applied, for example, during cooling + ice heat storage operation.

FIG. 44 shows an example in which the heat exchanger 51a operates as a condenser, the heat exchanger 51b operates as a first evaporator, and the heat exchanger 51c operates as a second evaporator. 2 on-off valve 22, 4th on-off valve 24, on-off valves 27a, 28
a, 26b, 28b, 26c, 27c, 30a, 30b
Is closed (filled in the figure). The arrow indicates the flow of the refrigerant.

The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 passes through the third on-off valve 23, the high-pressure gas communication pipe 65, and the refrigerant gas discharged from the second compressor 2 and the first high-pressure gas pipe 6.
At 1, they merge, pass through the on-off valve 26a, flow into the heat exchanger 51a, and are condensed and liquefied. This liquid refrigerant is used for the electric expansion valve 3
1a to flow into the liquid receiver 69, and a part of it flows through the electric expansion valve 31b into a low-pressure two-phase state.
It flows into the heat exchanger 51b, which is an evaporator, and is vaporized and gasified. This gas refrigerant passes through the second high-pressure gas pipe 62 to the fifth
It is sucked into the first compressor 1 through the on-off valve 25, the second accumulator 12, and the second check valve. On the other hand, the remaining liquid refrigerant that has flowed into the liquid pipe 64 passes through the electric expansion valve 31c into a low-pressure two-phase state, flows into the heat exchanger 51c that is the second evaporator, and is vaporized and gasified. The gas refrigerant passes through the low pressure gas pipe 63, the first accumulator 11, and is sucked into the second compressor 2. Thus, in this operation mode, the heat exchanger 51a obtains the condensation temperature, the heat exchanger 51b obtains the first evaporation temperature, and the heat exchanger 51c obtains the second evaporation temperature.

Next, referring to FIG. 45, one condensation temperature and 2
The operation will be described in the case where the difference between the condensation temperature and the evaporation temperature is relatively large when three temperatures are generated to generate one evaporation temperature. This operation mode is applied, for example, during cooling + ice heat storage + high-temperature hot water supply operation. In FIG. 45, the heat exchanger 51
a is a condenser, heat exchanger 51b is a first evaporator, heat exchanger 5
1c shows an example in which it operates as a second evaporator,
Open / close valve 23, fifth open / close valve 25, open / close valves 27a, 28a,
26b, 28b, 26c, 27c and the on-off valve 30b are closed.

The high-temperature and high-pressure refrigerant gas discharged from the first compressor 1 flows into the high-pressure gas pipe 61, passes through the on-off valve 26a, flows into the heat exchanger 51a, and is condensed and liquefied. The liquid refrigerant passes through the electronic expansion valve 31a and receives the liquid receiver 69.
And a part thereof flows through the electronic expansion valve 31b into a low-pressure two-phase state and then flows into the heat exchanger 51b which is the first evaporator to be vaporized and gasified. This gas refrigerant is used for the on-off valve 2
After passing through 7b, the seventh on-off valve 30a, and the liquid refrigerant bypassed via the bypass passage 68, the medium pressure gas pipe 62 is joined.
Through the first opening / closing valve 21, merges with the discharge gas of the second compressor, passes through the fourth opening / closing valve 24, the second opening / closing valve 22, and is sucked into the first compressor 1. On the other hand, the remaining liquid refrigerant that has flowed into the liquid receiver 68 passes through the electronic expansion valve 31c, enters a low-pressure two-phase state, flows into the heat exchanger 51c that is the second evaporator, and is vaporized and gasified. This gas refrigerant is used for the on-off valve 2
8c, the low pressure gas pipe 63, the first accumulator 11, and the second compressor 2. As described above, in this operation mode, the liquid refrigerant is mixed with the discharge gas of the second compressor 2 that is the low-stage compressor to be the gas that is sucked into the first compressor 1 that is the high-stage compressor. Thus, the two-stage compression operation is efficiently performed while preventing the discharge temperature from rising, and the condensing temperature is obtained by the heat exchanger 51a, the first evaporating temperature is obtained by the heat exchanger 51b, and the second evaporating temperature is obtained by the heat exchanger 51c. . In addition, in this configuration, the liquid back is prevented by the gas-liquid separation effect of the liquid receiver, and the cooling effect of directly cooling can be improved.

Example 9. 46: is a block diagram of the refrigerant circuit of the vapor compression type cycle of Example 9. FIG. In FIG. 46,
1 is a first compressor, 2 is a second compressor, 61 is a high pressure gas pipe,
63 is a low pressure gas pipe, 62 is a medium pressure gas pipe, 64 is a liquid pipe, 6
5a, 65b, 65c are heat exchangers, and the heat exchangers include high-pressure gas pipe 61, low-pressure gas pipe 63, and medium-pressure gas pipe 62, and open / close valves 26a, 27a, 28a and 26b, 27b, 28b, respectively.
And 26c, 27c, and 28c, and the liquid pipe 64 is connected to the electronic expansion valve 31 which is a flow control valve.
They are connected via a, 31b, and 31c, respectively. 7
2 is a first discharge pipe that connects the discharge side of the first compressor 1 and the high-pressure gas pipe 61 via the first on-off valve 121, and 74 is a second
The discharge side of the compressor and the medium pressure gas pipe 62 are connected to the second opening / closing valve 123.
A second discharge pipe connected via the first suction pipe of the first compressor 1 and a first suction pipe connected to the intermediate pressure gas pipe 62 via the third on-off valve 125, and a second compression pipe 78. The second suction pipe connected to the suction side of the machine 2 and the low pressure gas pipe 63 via the fourth on-off valve 127, and 80 is the medium pressure gas pipe 62 and the second suction pipe 7.
8 is a first bypass pipe that connects the first low pressure gas pipe 63 and the first suction pipe 76 with a sixth open / close valve 131. A pipe, 83 is a discharge side connecting pipe that connects the first discharge pipe 72 and the second discharge pipe 74 via the seventh and eighth opening / closing valves 134 and 135, and 86 is a first suction pipe 76 and the first suction pipe 76. 2 suction pipe 78
And a suction side connecting pipe for connecting the and 9 via the ninth and tenth on-off valves 137 and 138, and 89 between the seventh and eighth on-off valves 137 and 138 of the suction side connecting pipe 86 and a discharge side connecting pipe. A third bypass pipe 91 for connecting the ninth and tenth on-off valves 134 and 135 of 83 through the eleventh on-off valve 140.
Is a fourth bypass pipe connecting the first discharge pipe 72 and the medium pressure gas pipe 62 via the twelfth on-off valve 142, and 93 is the second discharge pipe 74 and the high pressure gas pipe 61. On-off valve 1
It is a fifth bypass pipe connected via 44. The multi-temperature generation circuit according to the ninth embodiment has six operation modes as shown in Table 1. The six operating modes are shown in FIG.
It demonstrates using 7-FIG.

First, with reference to FIG. 47, an operation will be described in which two condensation temperatures, one condensation temperature and one evaporation temperature, are generated and the difference between the condensation temperature and the evaporation temperature is relatively small. This operation mode is applied, for example, during normal cooling or heating. In FIG. 47, the heat exchanger 51a
Is a condenser, the heat exchanger 51b is stopped, and the heat exchanger 51c operates as an evaporator.
1, 4th on-off valve 127, 7th on-off valve 134, 8th on-off valve 135, 9th on-off valve 137, 10th on-off valve 1
38 and the on-off valves 26a and 28c are closed. The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 and the second compressor 2 joins in the high-pressure gas pipe 61, flows into the heat exchanger 51a through the on-off valve 26a, and is condensed and liquefied. The liquid refrigerant flows through the electric expansion valve 31a into the liquid pipe 64, and then flows through the electric expansion valve 31c into a low-pressure two-phase state into the heat exchanger 51c to be vaporized and gasified. Thus, in this operation mode, the heat exchanger 51a obtains the condensation temperature and the heat exchanger 51c obtains the evaporation temperature.

Next, referring to FIG. 48, one condensing temperature and 1
An operation will be described in the case where the difference between the condensation temperature and the evaporation temperature is relatively large when two temperatures are generated to generate one evaporation temperature. This operation mode is applied, for example, to hot water supply or hot water supply + ice heat storage. In FIG. 48, for example, the heat exchanger 5
1a is a condenser, heat exchanger 51b is stopped, heat exchanger 51c
Shows an example of operating as an evaporator. Two
6a and 28c are open.

The refrigerant gas discharged from the second compressor 2 is
After passing through the eighth opening / closing valve 135, the eleventh opening / closing valve 140, and the ninth opening / closing valve 137, the high temperature high pressure refrigerant gas is sucked into the first compressor 1 and flows into the high pressure gas pipe 61. On-off valve 26a
Through which it flows into the heat exchanger 51a and is condensed and liquefied. The liquid refrigerant flows through the electric expansion valve 31a into the liquid pipe 64, and then flows through the electric expansion valve 31c into a low-pressure two-phase state into the heat exchanger 51c to be vaporized and gasified. This refrigerant gas passes through the low-pressure gas pipe 63 and the fourth on-off valve 12
7 and the second suction pipe 78 to be sucked into the second compressor 2.

In the above description, the second compressor 2 is on the low stage side,
The operation when the first compressor 1 is on the high stage side has been described, but the sixth opening / closing valve 131, the seventh opening / closing valve 134, and the first opening / closing valve 134
0 opening / closing valve 138, 11th opening / closing valve 140, 12th opening / closing valve 142, 13th opening / closing valve 144, and opening / closing valve 27a,
With 28c open, the refrigerant gas that has flowed into the heat exchanger 51c and has been vaporized and gasified is sucked into the first compressor 1 from the low-pressure gas pipe 63 through the sixth opening / closing valve 131 and the first suction pipe 76, The discharge gas and a part of the refrigerant in the medium-pressure gas pipe 62 from the twelfth on-off valve 142 are sucked into the second compressor 2, and the discharge gas is discharged from the thirteenth on-off valve 144 to the high-pressure gas pipe 61.
You may make it flow into. As described above, in this operation mode, the two-stage compression operation is performed, and the heat exchanger 51a obtains the condensation temperature and the heat exchanger 51c obtains the evaporation temperature.

Next, referring to FIG. 49, two condensing temperatures and 1
An operation will be described in the case where the difference between the condensation temperature and the evaporation temperature is relatively small when three temperatures are generated to generate one evaporation temperature. This operation mode is applied, for example, during normal heating + relatively low hot water supply operation. In FIG. 49, for example, the heat exchanger 51a operates as a first condenser, the heat exchanger 51b operates as a second condenser, and the heat exchanger 51c operates as an evaporator. On-off valve 123, fourth
On-off valve 127, tenth on-off valve 138 and on-off valve 26
The a, 27b and 28c are closed. First compressor 1
The high-temperature high-pressure refrigerant gas discharged from the above flows into the high-pressure gas pipe 61, passes through the on-off valve 26a, flows into the heat exchanger 51a which is the first condenser, and is condensed and liquefied. This liquid refrigerant flows into the liquid pipe 64 through the electric expansion valve 31a. on the other hand,
The high-temperature high-pressure refrigerant gas discharged from the second compressor 2 is
Through the on-off valve 123, into the medium-pressure gas pipe 62, and through the on-off valve 27b into the heat exchanger 51b which is the second condenser to be condensed and liquefied. This liquid refrigerant is the electric expansion valve 31b.
To flow into the liquid pipe 64 and merge with the liquid refrigerant from the heat exchanger 65a which is the first condenser. The combined liquid refrigerant flows through the electric expansion valve 31c into a low-pressure two-phase state, flows into the heat exchanger 51c, and is vaporized and gasified. This gas refrigerant passes through the low-pressure gas pipe 63 and the fourth on-off valve 12
7 and the second suction pipe 78, and is sucked into the first compressor 1 and the second compressor 2.

In the above description, the refrigerant discharged from the first compressor 1 is made to flow from the opening / closing valve 26a into the heat exchanger 51a which is the first condenser, and the refrigerant discharged from the second compressor 2 is made to flow to the second opening / closing valve 27b. Although it is flowing into the heat exchanger 51b which is a condenser,
The on-off valves 26a and 27b are closed and the on-off valves 27a and 26b are opened, so that the refrigerant discharged from the first compressor 1 is the heat exchanger 51b which is the second condenser, and the refrigerant discharged from the second compressor 2 is the first condenser. May be made to flow into the heat exchanger 51a. Therefore,
The first depending on the load states of the heat exchanger 51a and the heat exchanger 51b.
The refrigerant from the compressor 1 and the second compressor 2 can be introduced into the heat exchanger by switching the open / close valve. Thus, in this operation mode, the heat exchanger 51a has the first condensing temperature, the heat exchanger 51b has the second condensing temperature, and the heat exchanger 5 has the second condensing temperature.
The evaporation temperature is obtained in 1c.

Next, referring to FIG. 50, two condensing temperatures and 1
The operation will be described in the case where the difference between the condensation temperature and the evaporation temperature is relatively large when three temperatures are generated to generate one evaporation temperature. This operation mode is applied, for example, during normal heating + relatively high hot water supply operation. In FIG. 50, for example, the heat exchanger 51a operates as a first condenser, the heat exchanger 51b operates as a second condenser, and the heat exchanger 51c operates as an evaporator. Open / close valve 123, fourth open / close valve 127, eighth open / close valve 135, ninth open / close valve 13
7, 11th on-off valve 140 and on-off valves 26a, 27b, 2
8c is open. A part of the refrigerant gas discharged from the second compressor 2 passes through the eighth opening / closing valve 135, the eleventh opening / closing valve 140, and the ninth opening / closing valve 137, and the first compressor 1
Is sucked into the high-temperature high-pressure refrigerant gas and becomes a high-pressure gas pipe 6
Flow into 1. This gas refrigerant flows through the opening / closing valve 26a into the heat exchanger 51a, which is the first condenser, and is condensed and liquefied. The liquid refrigerant passes through the electric expansion valve 31b and the liquid pipe 6
Inflow to 4. On the other hand, the rest of the refrigerant gas discharged from the second compressor 2 flows into the medium-pressure gas pipe 62 through the second opening / closing valve 123, passes through the opening / closing valve 27b, and is the heat exchanger that is the second condenser. It flows into 51b and is condensed and liquefied. The liquid refrigerant flows into the liquid pipe 64 through the electric expansion valve 31 and joins with the liquid refrigerant from the heat exchanger 51a which is the first condenser. The combined liquid refrigerant flows through the electric expansion valve 31c into a low-pressure two-phase state, flows into the heat exchanger 51c, and is vaporized and gasified. This refrigerant gas is sucked into the second compressor 2 through the low pressure gas pipe 63, the fourth on-off valve 127 and the second suction pipe 78.

In the above description, the second compressor 2 is on the low stage side,
The operation when the first compressor 1 is on the high stage side has been described, but the first on-off valve 121, the sixth on-off valve 131, and the seventh
The open / close valve 134, the tenth open / close valve 138, the eleventh open / close valve 140, and the open / close valves 27a, 28c are opened, and the refrigerant gas that has flowed into the heat exchanger 51c and is vaporized and gasified is supplied from the low pressure gas pipe 63 to the first open / close valve. The first compressor 1 may be sucked through the on-off valve 131 of No. 6 and the first suction pipe 76, and the discharge gas may be sucked into the second compressor 2. Thus, in this operation mode, the first condensing temperature in the heat exchanger 51a,
The second condensing temperature is obtained by the heat exchanger 51b, and the evaporation temperature is obtained by the heat exchanger 51c.

Next, referring to FIG. 51, one condensing temperature and 2
An operation will be described in the case where the difference between the condensation temperature and the evaporation temperature is relatively small when three temperatures are generated to generate one evaporation temperature. This operation mode is applied, for example, during normal cooling + ice heat storage operation. In FIG. 51, the heat exchanger 51a is a condenser, the heat exchanger 51b is a first evaporator, and the heat exchanger 51c.
Shows an example of operating as a second evaporator, and the first opening / closing valve 121, the third opening / closing valve 125, and the fourth opening / closing valve 12 are shown.
The seventh, seventh on-off valve 134, the eighth on-off valve 135 and the on-off valves 26a, 27b, 28c are open. The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 merges with the refrigerant discharged from the second compressor 2 that has passed through the first on-off valve 121 at the high-pressure gas pipe 61, passes through the on-off valve 26a, and then enters the heat exchanger. It flows into 51a and is liquefied by a condenser. This liquid refrigerant is an electric expansion valve 3
It flows through the liquid pipe 64 through 1a, and a part of it flows through the electric expansion valve 31b into a low-pressure two-phase state and flows into the heat exchanger 51b which is the first evaporator to be vaporized and gasified. This refrigerant gas passes through the medium-pressure gas pipe 62 and the third on-off valve 125,
It is sucked into the first compressor 1 via the first suction pipe 76.
On the other hand, the remaining liquid refrigerant flowing into the liquid pipe 64 passes through the electric expansion valve 31c into a low-pressure two-phase state, flows into the heat exchanger 51c that is the second evaporator, and is evaporated and gasified. This gas refrigerant passes through the low-pressure gas pipe 63 and the fourth on-off valve 12
7 and the second suction pipe 78 to be sucked into the second compressor 2.

In the above description, the refrigerant gas in the medium pressure gas pipe 62 is sucked into the first compressor 1 and the refrigerant gas in the low pressure gas pipe 63 is sucked into the second compressor 2. However, as shown in FIG. 1 open / close valve 121, 5th open / close valve 129, 6th open / close valve 13
1, the seventh on-off valve 134, the eighth on-off valve 135 and the on-off valves 26a, 27b, 28c are opened, and the medium pressure gas pipe 62 is opened.
The refrigerant gas may be sucked into the second compressor 2, and the refrigerant gas in the low pressure gas pipe 63 may be sucked into the first compressor 1. Therefore, the refrigerant can be introduced from the compressor by switching the opening / closing valve according to the heat load of the heat exchanger 51c and the heat exchanger 51b. Thus, in this operating mode, the heat exchanger 5
The condensation temperature is obtained at 1a, the first evaporation temperature is obtained at the heat exchanger 51b, and the second evaporation temperature is obtained at the heat exchanger 51c.

Next, with reference to FIG. 53, an operation will be described in the case where the difference between the condensation temperature and the evaporation temperature is relatively large at the time of generating three temperatures for generating one condensation temperature and two evaporation temperatures. This operation mode is applied, for example, during normal cooling + ice heat storage + high-temperature hot water supply operation. FIG. 53 shows an example in which the heat exchanger 51a operates as a condenser, the heat exchanger 51b operates as a first evaporator, and the heat exchanger 51c operates as a second evaporator.
First on-off valve 121, second on-off valve 123, fourth on-off valve 127, eighth on-off valve 135, eleventh on-off valve 140
The open / close valves 26a, 27b, 28c are opened.
The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 flows into the high-pressure gas pipe 61, passes through the opening / closing valve 26a, and the heat exchanger 5
It flows into 1a and is condensed and liquefied. The liquid refrigerant flows into the liquid pipe 64 through the electric expansion valve 31a, and a part of the liquid refrigerant flows through the electric expansion valve 31b into a low-pressure two-phase state, which is the heat exchanger 51b as the first evaporator. And is vaporized into gas.
This refrigerant gas merges with the discharge gas of the second compressor 2 through the intermediate pressure gas pipe 62 and the second on-off valve 123, and then the eighth on-off valve 135, the eleventh on-off valve 140, and the ninth on-off valve. On-off valve 1
It is sucked into the first compressor 1 via 37. On the other hand, the liquid pipe 64
The remaining liquid refrigerant that has flowed into the heat exchanger 51c, which is the second evaporation, is in a low-pressure two-phase state through the electric expansion valve 31c.
And is vaporized into gas. The gas refrigerant passes through the low pressure gas pipe 63 and the fourth on-off valve 127 and the second suction pipe 78.
And is sucked into the second compressor 2.

In the above description, the second compressor 2 is on the low stage side,
The operation when the first compressor 1 is on the high stage side has been described. However, as shown in FIG. 54, a sixth opening / closing valve 131, a seventh opening / closing valve 134, a tenth opening / closing valve 138, and an eleventh opening / closing valve. Valve 140, twelfth on-off valve 142, thirteenth on-off valve 144
And the open / close valves 27a and 28c are opened, and the heat exchanger 5
Refrigerant gas that has flowed into 1c and has been vaporized and gasified is supplied to the low-pressure gas pipe 6
3 to the sixth on-off valve 131, the first suction pipe 76 to suck into the first compressor 1, the discharge gas and a part of the refrigerant of the medium-pressure gas pipe 62 from the twelfth on-off valve 142. The second compressor 2 may be sucked and its discharge gas may flow into the high pressure gas pipe 61 from the thirteenth on-off valve 144. Thus, in this operation mode, the heat exchanger 51a has the first condensation temperature, the heat exchanger 51b has the first evaporation temperature, and the heat exchanger 5 has the first evaporation temperature.
A second evaporation temperature is obtained at 1c.

Example 10. FIG. 55 is a configuration diagram of the refrigerant circuit of the vapor compression cycle of the tenth embodiment. In FIG. 55, 1 is a first compressor, 2 is a second compressor, 61 is a high pressure gas pipe, 63 is a low pressure gas pipe, 62 is a medium pressure gas pipe, 64 is a liquid pipe, 51a, 51b, 51c are heat exchanges. The heat exchanger includes a high-pressure gas pipe 61, a low-pressure gas pipe 63, and an intermediate-pressure gas pipe 62, and open / close valves 26a, 27a, 28a and 26b, 27b, respectively.
28b and 26c, 27c, 28c are branched and connected to the liquid pipe 64 via electronic expansion valves 31a, 31b, 31c which are flow control valves. Reference numeral 72 denotes a first discharge pipe that connects the discharge side of the first compressor 1 and the high-pressure gas pipe 61 via the first opening / closing valve 121.
Reference numeral 4 is a second discharge pipe that connects the discharge side of the second compressor and the medium pressure gas pipe 62 via the second opening / closing valve 123, and 76 is a first discharge pipe.
The first suction pipe connected to the four-way valve 150 via the suction side of the compressor 1 and the third on-off valve 125, 78 is a four-way valve via the suction side of the second compressor 2 and the fourth on-off valve 127. A second suction pipe connected to 150, 83 is a discharge side connection pipe connecting the first discharge pipe 72 and the second discharge pipe 74 through the seventh and eighth on-off valves 134 and 135, and 86 is The first suction pipe 76 and the second suction pipe 78 are connected to the ninth and tenth open / close valves 137, 1
The suction side connection pipe connected via 38, 89 is between the seventh and eighth on-off valves 137, 138 of the suction side connection pipe 86, and the ninth and tenth on-off valves 134, 138 of the discharge side connection pipe 83. 135
And a third bypass pipe connecting between and via the eleventh on-off valve 140, and 91 is a first discharge pipe 72 and an intermediate pressure gas pipe 62.
The fourth bypass pipe 93 that connects the second discharge pipe 74 and the high-pressure gas pipe 61 via the thirteenth on-off valve 144 is a fourth bypass pipe 93 that connects is there. The four-way valve 150 includes the medium pressure gas pipe 62 and the low pressure gas pipe 6.
3, the first suction pipe 76, the second suction pipe 78 is connected,
Medium pressure gas pipe 62 and first suction pipe 76, low pressure gas pipe 63 and second suction pipe 78, or medium pressure gas pipe 62 and second suction pipe 78, low pressure gas pipe 63 and first suction pipe 76. Switch and connect. The multi-temperature generation circuit of this embodiment has six operation modes as shown in Table 1 similarly to the ninth embodiment, and these six operation modes will be described below with reference to FIGS. 56 to 66.

First, with reference to FIG. 56, an operation will be described in which two condensation temperatures, one condensation temperature and one evaporation temperature, are generated and the difference between the condensation temperature and the evaporation temperature is relatively small. This operation mode is applied, for example, during normal cooling or heating. FIG. 56 shows an example in which the heat exchanger 51a operates as a condenser, the heat exchanger 51b stops, and the heat exchanger 51c operates as an evaporator. The first on-off valve 121,
Fourth opening / closing valve 127, seventh opening / closing valve 134, eighth opening / closing valve 135, ninth opening / closing valve 137, tenth opening / closing valve 138
And the on-off valves 26a and 28c are opened, and the four-way valve 150
Is switched so that the low-pressure gas pipe 63 and the second suction pipe 78 communicate with each other. First compressor 1 and second compressor 2
The high-temperature high-pressure refrigerant gas discharged from the high-pressure gas pipe 61 merges in the high-pressure gas pipe 61, flows into the heat exchanger 51a through the on-off valve 26a, and is condensed and liquefied. This liquid refrigerant is used in the electric expansion valve 31.
flowing into the liquid pipe 64 through a, flowing into the heat exchanger 51c through the electric expansion valve 31c in a low-pressure two-phase state,
Evaporative gasification. This refrigerant gas is used as a low pressure gas pipe 6
3 and flows from the four-way valve 150 into the first compressor 1 and the second compressor through the second suction pipe 78 and the suction side connecting pipe 86. Thus, in this operation mode, the heat exchanger 51a
To obtain the condensation temperature, and the heat exchanger 51c to obtain the evaporation temperature.

Next, referring to FIG. 57, one condensing temperature and 1
An operation will be described in the case where the difference between the condensation temperature and the evaporation temperature is relatively large when two temperatures are generated to generate one evaporation temperature. This operation mode is applied, for example, to hot water supply or hot water supply + ice heat storage. In FIG. 57, for example, the heat exchanger 5
1a is a condenser, heat exchanger 51b is stopped, heat exchanger 51c
Shows an example of operating as an evaporator. Two
6a and 28c are opened, and the four-way valve 150 is the low pressure gas pipe 6
3 and the second suction pipe 78 are switched to communicate with each other. The refrigerant gas discharged from the second compressor 2 has an eighth opening / closing valve 135, an eleventh opening / closing valve 140, and a ninth opening / closing valve 1.
The high-temperature high-pressure refrigerant gas is drawn into the first compressor 1 through 37 and flows into the high-pressure gas pipe 61. It flows into the heat exchanger 51a through the on-off valve 26a and is condensed and liquefied. This liquid refrigerant flows through the electric expansion valve 31a into the liquid pipe 64, passes through the electric expansion valve 31c into a low-pressure two-phase state, flows into the heat exchanger 51c, and is vaporized and gasified. This refrigerant gas is sucked into the second compressor 2 through the low-pressure gas pipe 63, the four-way valve 150, the fourth opening / closing valve 127, and the second suction pipe 78.

In the above description, the second compressor 2 is on the low stage side,
Although the operation when the first compressor 1 is set to the high stage side has been described, as shown in FIG. 58, the third on-off valve 125, the seventh on-off valve 134, the tenth on-off valve 138, and the eleventh on-off valve. Valve 140, thirteenth on-off valve 144 and on-off valves 27a, 28c
Is opened, and the four-way valve 150 is switched so that the low pressure gas pipe 63 and the first suction pipe 76 are communicated with each other, whereby the refrigerant gas flowing into the heat exchanger 51c and vaporized into a sixth gas is supplied from the low pressure gas pipe 63 to the sixth gas. Through the opening / closing valve 131 and the first suction pipe 76 of the first compressor 1, and the discharge gas of the second compressor 2 is sucked into the high pressure gas pipe 61 of the thirteenth opening / closing valve 144. You may make it flow in. As described above, in this operation mode, the two-stage compression operation is performed, and the heat exchanger 51a obtains the condensation temperature and the heat exchanger 51c obtains the evaporation temperature.

Next, referring to FIG. 59, two condensing temperatures and 1
An operation will be described in the case where the difference between the condensation temperature and the evaporation temperature is relatively small when three temperatures are generated to generate one evaporation temperature. This operation mode is applied, for example, during normal heating + relatively low hot water supply operation. FIG. 59 shows an example in which the heat exchanger 51a operates as a first condenser, the heat exchanger 51b operates as a second condenser, and the heat exchanger 51c operates as an evaporator. On-off valve 123, fourth
On-off valve 127, tenth on-off valve 138 and on-off valve 26
The a, 27b, and 28c are opened, and the four-way valve 150 is switched to connect the low pressure gas pipe 63 and the second suction pipe 78. The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 flows into the high-pressure gas pipe 61, passes through the on-off valve 26a, flows into the heat exchanger 51a that is the first condenser, and is condensed and liquefied. This liquid refrigerant flows into the liquid pipe 64 through the electric expansion valve 31a. On the other hand, the high-temperature high-pressure refrigerant gas discharged from the second compressor 2 flows into the medium-pressure gas pipe 62 through the second opening / closing valve 123, passes through the opening / closing valve 27b, and is the second condenser heat exchanger 51c. And is condensed and liquefied. The liquid refrigerant flows into the liquid pipe 64 through the electric expansion valve 31b and merges with the liquid refrigerant from the heat exchanger 51a which is the first condenser. The combined liquid refrigerant flows through the electric expansion valve 31c into a low-pressure two-phase state, flows into the heat exchanger 51c, and is vaporized and gasified. This refrigerant gas is a low pressure gas pipe 6
Through the four-way valve 150 to the fourth on-off valve 127, the second
It is sucked into the first compressor 1 and the second compressor 2 via the suction pipe 78.

In the above description, the refrigerant discharged from the first compressor 1 is made to flow from the opening / closing valve 26a into the heat exchanger 51a which is the first condenser, and the refrigerant discharged from the second compressor 2 is made to flow from the opening / closing valve 27b to the second opening / closing valve 27b. Although it is flowing into the heat exchanger 51b which is a condenser,
As shown in FIG. 60, a fourth on-off valve 127, a ninth on-off valve 137, a tenth on-off valve 138, and a twelfth on-off valve 142.
And the thirteenth on-off valve 144 are opened so that the first compressor 1
The discharge refrigerant may be caused to flow into the heat exchanger 51b that is the second condenser, and the discharge refrigerant from the second compressor 2 may be caused to flow into the heat exchanger 51a that is the first condenser. Therefore, the refrigerant from the first compressor 1 and the second compressor 2 can be introduced into the heat exchanger by switching the open / close valves according to the load states of the heat exchanger 51a and the heat exchanger 51b. As described above, in this operation mode, the first heat exchanger 51a has the first condensing temperature and the heat exchanger 51a.
The second condensation temperature is obtained at b, and the evaporation temperature is obtained at the heat exchanger 51c.

Next, referring to FIG. 61, two condensing temperatures and 1
The operation will be described in the case where the difference between the condensation temperature and the evaporation temperature is relatively large when three temperatures are generated to generate one evaporation temperature. This operation mode is applied, for example, during normal heating + relatively high hot water supply operation. In FIG. 61, for example, the heat exchanger 51a operates as a first condenser, the heat exchanger 51b operates as a second condenser, and the heat exchanger 51c operates as an evaporator. Open / close valve 123, fourth open / close valve 127, eighth open / close valve 135, ninth open / close valve 13
7, 11th on-off valve 140 and on-off valves 26a, 27b, 2
8c is opened and the four-way valve 150 is connected to the low pressure gas pipe 63 and the first
It is switched so as to communicate with the suction pipe 76 of. A part of the refrigerant gas discharged from the second compressor 2 is part of the eighth opening / closing valve 135, the eleventh opening / closing valve 140, and the ninth opening / closing valve 1.
After passing through 37, it is sucked into the first compressor 1, becomes high-temperature high-pressure refrigerant gas, and flows into the high-pressure gas pipe 61. This gas refrigerant passes through the on-off valve 26a and the heat exchanger 51, which is the first condenser.
It flows into a and is condensed and liquefied. This liquid refrigerant flows into the liquid pipe 64 through the electric expansion valve 31b. On the other hand, the rest of the refrigerant gas discharged from the second compressor 2 is the second on-off valve 1
After passing through 23, it flows into the medium pressure gas pipe 62, passes through the on-off valve 27b, flows into the heat exchanger 51b which is the second condenser, and is condensed and liquefied. This liquid refrigerant flows into the liquid pipe 64 through the electric expansion valve 31b, and merges with the liquid refrigerant from the heat exchanger 51a which is the first condenser. The combined liquid refrigerant passes through the electric expansion valve 31c to become a low-pressure two-phase state and the heat exchanger 51c.
And is vaporized into gas. This refrigerant gas is sucked into the second compressor 2 through the low-pressure gas pipe 63, the four-way valve 150, the fourth opening / closing valve 127, and the second suction pipe 78.

In the above description, the second compressor 2 is on the low stage side,
The operation when the first compressor 1 is on the high stage side has been described. However, as shown in FIG. Valve 140, twelfth on-off valve 142 and thirteenth on-off valve 144
Is opened and the four-way valve 150 is connected to the low pressure gas pipe 63.
And the second suction pipe 78 are communicated with each other, and the refrigerant gas that has flowed into the heat exchanger 51c and has been vaporized and gasified is passed from the low pressure gas pipe 63 through the four-way valve 150 and the first suction pipe 76 to the first suction pipe 76. The gas is sucked into the compressor 1, and its discharge gas is supplied to the second compressor 2
May be inhaled. Thus, in this operation mode, the heat exchanger 51a obtains the first condensation temperature, the heat exchanger 51b obtains the second condensation temperature, and the heat exchanger 51c obtains the evaporation temperature.

Next, referring to FIG. 63, one condensing temperature and 2
An operation will be described in the case where the difference between the condensation temperature and the evaporation temperature is relatively small when three temperatures are generated to generate one evaporation temperature. This operation mode is applied, for example, during normal cooling + ice heat storage operation. In FIG. 63, the heat exchanger 51a is a condenser, the heat exchanger 51b is a first evaporator, and the heat exchanger 51c.
Shows an example of operating as a second evaporator, and the first opening / closing valve 121, the third opening / closing valve 125, and the fourth opening / closing valve 12 are shown.
7, the seventh opening / closing valve 134, the eighth opening / closing valve 135, and the opening / closing valves 26a, 27b, 28c are opened, and the four-way valve 150 is connected to the low pressure gas pipe 63, the second suction pipe 78, and the intermediate pressure gas pipe 62. It is switched so that the first suction pipe 76 communicates. The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 is
The high pressure gas pipe 61 joins the refrigerant gas discharged from the second compressor 2 through the seventh and eighth on-off valves 135 and 134 to open and close the on-off valve 26a.
Through which it flows into the heat exchanger 51a and is condensed and liquefied. The liquid refrigerant flows into the liquid pipe 64 through the electric expansion valve 31a, and a part of the liquid refrigerant flows through the electric expansion valve 31b into a low-pressure two-phase state, which is the heat exchanger 51b as the first evaporator. And is vaporized into gas. This refrigerant gas is sucked into the first compressor 1 from the four-way valve 150 through the medium pressure gas pipe 62, the third opening / closing valve 125, and the first suction pipe 76. On the other hand, the remaining liquid refrigerant flowing into the liquid pipe 64 is the electric expansion valve 31c.
Through it, it becomes a low-pressure two-phase state, flows into the heat exchanger 51c which is the second evaporator, and is evaporated and gasified. This gas refrigerant is sucked into the second compressor 2 through the low pressure gas pipe 63, the four-way valve 150, the fourth opening / closing valve 127, and the second suction pipe 78.

In the above description, the refrigerant gas in the medium pressure gas pipe 62 is sucked into the first compressor 1 and the refrigerant gas in the low pressure gas pipe 63 is sucked into the second compressor 2. However, as shown in FIG. 1 opening / closing valve 121, 3rd opening / closing valve 125, 4th opening / closing valve 12
7, the seventh on-off valve 134, the eighth on-off valve 135 and the on-off valves 26a, 27b, 28c are opened, and the four-way valve 150 is connected to the low-pressure gas pipe 63, the first suction pipe 76, and the medium-pressure gas pipe 62. The refrigerant gas in the medium-pressure gas pipe 62 may be sucked into the second compressor 2 and the refrigerant gas in the low-pressure gas pipe 63 may be sucked into the first compressor 1 by switching the second suction pipe 78 to communicate with each other. Therefore, the refrigerant can be introduced from the compressor by switching the opening / closing valve according to the heat load of the heat exchanger 51c and the heat exchanger 51b. As described above, in this operation mode, the heat exchanger 51a is operated at the condensing temperature and the heat exchanger 51b.
Then, the first evaporation temperature is obtained, and the second evaporation temperature is obtained by the heat exchanger 51c.

Next, with reference to FIG. 65, an operation will be described in the case of generating three temperatures for generating one condensation temperature and two evaporation temperatures and when the difference between the condensation temperature and the evaporation temperature is relatively large. This operation mode is applied, for example, during normal cooling + ice heat storage + high-temperature hot water supply operation. FIG. 65 shows an example in which the heat exchanger 51a operates as a condenser, the heat exchanger 51b operates as a first evaporator, and the heat exchanger 51c operates as a second evaporator.
First on-off valve 121, second on-off valve 123, fourth on-off valve 127, eighth on-off valve 135, eleventh on-off valve 140
The open / close valves 26a, 27b, 28c are opened, and the four-way valve 150 is switched so as to connect the low pressure gas pipe 63 and the second suction pipe 78. The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 flows into the high-temperature gas pipe 61, passes through the on-off valve 26a, flows into the heat exchanger 51a, and is condensed and liquefied. This liquid refrigerant passes through the electric expansion valve 31a and the liquid pipe 6
4 and a part of it flows through the electric expansion valve 31b into a low-pressure two-phase state and the heat exchanger 51b which is the first evaporator.
And is vaporized into gas. The refrigerant gas passes through the intermediate pressure gas pipe 62, the second opening / closing valve 123, and the second compressor 2
Is discharged to the first compressor 1 through the eighth opening / closing valve 135, the eleventh opening / closing valve 140, and the ninth opening / closing valve 137. On the other hand, the remaining liquid refrigerant flowing into the liquid pipe 64 passes through the electric expansion valve 31c into a low-pressure two-phase state and flows into the heat exchanger 51c, which is the second evaporator, to be vaporized and gasified. This gas refrigerant passes through the low-pressure gas pipe 63 and the four-way valve 1
50 is sucked into the second compressor 2 through the fourth opening / closing valve 127 and the second suction pipe 128.

In the above description, the second compressor 2 is on the low stage side,
The operation when the first compressor 1 is on the high stage side has been described, but as shown in FIG. 66, the seventh on-off valve 134, the first
By switching the zero open / close valve 138, the eleventh open / close valve 140, the twelfth open / close valve 142, the thirteenth open / close valve 144, and the four-way valve 150 so that the low pressure gas pipe 63 and the first suction pipe 76 communicate with each other. The refrigerant gas that has flowed into the heat exchanger 51c and has been vaporized and gasified is sucked into the first compressor 1 from the low-pressure gas pipe 63 through the four-way valve 150, the third opening / closing valve 125, and the first suction pipe 76, and The discharge gas and a part of the refrigerant in the medium pressure gas pipe 62 from the twelfth on-off valve 142 are sucked into the second compressor 2 so that the discharge gas flows into the high pressure gas pipe 61 from the thirteenth on-off valve 143. You may Thus, in this operation mode, the heat exchanger 51a obtains the condensation temperature, the heat exchanger 51b obtains the first evaporation temperature, and the heat exchanger 51c obtains the second evaporation temperature.

Example 11. 67 is a block diagram of the refrigerant circuit of the vapor compression cycle of the eleventh embodiment. 67, 1 is a first compressor, 2 is a second compressor, 61 is a high pressure gas pipe, 63 is a low pressure gas pipe, 62 is a medium pressure gas pipe, 64 is a liquid pipe, 51a, 51b, 51c are heat exchanges. The heat exchanger includes a high-pressure gas pipe 61, a low-pressure gas pipe 63, and an intermediate-pressure gas pipe 62, and open / close valves 26a, 27a, 28a and 26b, 27b, respectively.
28b and 26c, 27c, 28c are branched and connected to the liquid pipe 64 via electronic expansion valves 31a, 31b, 31c which are flow control valves. Reference numeral 180 denotes a second discharge pipe that connects the discharge side of the second compressor 2 and the high pressure gas pipe 61 via the first opening / closing valve 181.
A first discharge pipe 182 connects the discharge side of the first compressor 1 and the high-pressure gas pipe 61 via a first four-way valve 183.
Reference numeral 4 denotes a second suction pipe connecting the suction side of the second compressor 2 and the low-pressure gas pipe 63 via the second opening / closing valve 185, and 186 denotes a discharge side of the second compressor 2 and the first opening / closing valve. 181 is a first connecting pipe connecting the first four-way valve 183 and 188 is a pipe between the suction side of the second compressor 2 and the second on-off valve 185, and a second connecting pipe 188.
And a third connecting pipe 193 for connecting the first four-way valve 183 and the second four-way valve 187 via the third opening / closing valve 189. 19
5 is a fourth connecting pipe that branches from both sides of the third opening / closing valve 189 of the third connecting pipe 190 and is connected to the intermediate pressure gas pipe 62 via the fourth opening / closing valve 191 and the fifth opening / closing valve 192, respectively. And the fifth connecting pipe. The multi-temperature generation circuit of this embodiment has six operation modes as shown in Table 1 as in the ninth embodiment. Hereinafter, these six operation modes will be described with reference to FIGS. 68 to 7.
This will be described using 8.

First, with reference to FIG. 68, an operation will be described in which two condensation temperatures, one condensation temperature and one evaporation temperature, are generated and the difference between the condensation temperature and the evaporation temperature is relatively small. This operation mode is applied, for example, during normal cooling or heating. 68 shows an example in which the heat exchanger 51a operates as a condenser, the heat exchanger 51b stops, and the heat exchanger 51c operates as an evaporator. The first on-off valve 181,
The second on-off valve 185 and the on-off valves 26a and 28c are opened, the first four-way valve 183 is the first discharge pipe 182 and the high pressure gas pipe 61, and the second four-way valve 187 is the low pressure gas pipe 63 and the first four-way valve 187. It is switched so as to communicate with one suction pipe 194. The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 and the second compressor 2 merges in the high-pressure gas pipe 61, and the on-off valve 26
It flows into the heat exchanger 51a through a and is condensed and liquefied.
The liquid refrigerant flows through the electric expansion valve 31a into the liquid pipe 64, and then flows through the electric expansion valve 31c into a low-pressure two-phase state into the heat exchanger 51c to be vaporized and gasified. Then, this refrigerant gas flows into the low pressure gas pipe 63, and a part of the refrigerant gas passes through the second four-way valve 187 and the first suction pipe 194 to form the first gas.
It is sucked into the compressor 1. Then, the remaining refrigerant passes through the second suction pipe 184 and is sucked into the second compressor. in this way,
In this operation mode, the heat exchanger 51a obtains the condensation temperature and the heat exchanger 51c obtains the evaporation temperature.

Next, with reference to FIG. 69, an operation will be described in which two condensation temperatures, one condensation temperature and one evaporation temperature, are generated, and the difference between the condensation temperature and the evaporation temperature is relatively large. This operation mode is applied, for example, to hot water supply or hot water supply + ice heat storage. In FIG. 69, for example, the heat exchanger 51
In the example, a is a condenser, the heat exchanger 51b is stopped, and the heat exchanger 51c operates as an evaporator.
85, the third on-off valve 189 and the on-off valves 26a and 28c are opened, and the first four-way valve 183 is connected to the first discharge pipe 182.
And the high-pressure gas pipe 61, the first connecting pipe 186 and the third connecting pipe 1
89 and the second four-way valve 187 is connected to the first suction pipe 19
4 and the third connecting pipe 189 are switched to communicate with each other. The refrigerant gas discharged from the second compressor 2 is
Connection pipe 186, third connection pipe 189, second four-way valve 18
The high-temperature high-pressure refrigerant gas is sucked into the first compressor 1 through 7 and flows into the high-pressure gas pipe 61 from the first four-way valve 183. This refrigerant gas passes through the on-off valve 26a and the heat exchanger 51.
It flows into a and is condensed and liquefied. This liquid refrigerant flows into the liquid pipe 64 through the electric expansion valve 31a and flows into the electric expansion valve 31.
It becomes a low pressure two-phase state through c, flows into the heat exchanger 51c, and is vaporized and gasified. The refrigerant gas passes through the low-pressure gas pipe 63, the second opening / closing valve 185, the second suction pipe 184.
And is sucked into the second compressor 2.

In the above description, the second compressor 2 is on the low stage side,
The operation when the first compressor 1 is on the high stage side has been described, but as shown in FIG. 70, the third opening / closing valve 189 and the first four-way valve 183 are connected to the first discharge pipe 182 and the third discharge pipe 182. Connection pipe 189, the first connection pipe 186 and the high pressure gas pipe 61 are communicated with each other, and the second four-way valve 187 connects the low pressure gas pipe 63 and the first suction pipe 194 and the third connection pipe 189 and the second connection pipe 189. By switching the pipes 188 so as to communicate with each other, the refrigerant gas that has flowed into the heat exchanger 51c and has been vaporized and gasified is sucked into the first compressor 1 from the low-pressure gas pipe 63 through the second four-way valve 187, and the discharged gas thereof. The first four-way valve 183 and the third connecting pipe 19
6. The gas may be sucked into the second compressor 2 via the second connecting pipe 188 and the discharge gas thereof may flow into the high pressure gas pipe 61 from the first opening / closing valve 181. As described above, in this operation mode, the two-stage compression operation is performed, and the heat exchanger 51a obtains the condensation temperature and the heat exchanger 51c obtains the evaporation temperature.

Next, with reference to FIG. 71, an operation will be described in the case where the three condensing temperatures and the one evaporating temperature are generated and the difference between the condensing temperature and the evaporating temperature is relatively small. This operation mode is applied, for example, during normal heating + relatively low hot water supply operation. In FIG. 71, for example, the heat exchanger 51a operates as a first condenser, the heat exchanger 51b operates as a second condenser, and the heat exchanger 51c operates as an evaporator. The open / close valve 191 and the open / close valves 26a, 27b, 28c are opened, the first four-way valve 183 communicates the first discharge pipe 182 and the high pressure gas pipe 61, and the second four-way valve 187 the low pressure gas pipe 63. And the first suction pipe 194 are communicated with each other. The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 flows into the high-pressure gas pipe 61 via the first discharge pipe 182 and the first four-way valve 183, passes through the open / close valve 26a, and is the first condenser. It flows into the heat exchanger 51a and is condensed and liquefied. This liquid refrigerant flows into the liquid pipe 64 through the electric expansion valve 31a. On the other hand, the high-temperature high-pressure refrigerant gas discharged from the second compressor 2 passes through the first four-way valve 183 and the fourth on-off valve 191 and then the intermediate-pressure gas pipe 62.
To the heat exchanger 51b, which is the second condenser, through the on-off valve 27b, and is condensed and liquefied. The liquid refrigerant flows into the liquid pipe 64 through the electric expansion valve 31b and merges with the liquid refrigerant from the heat exchanger 51a which is the first condenser. The combined liquid refrigerant flows through the electric expansion valve 31c into a low-pressure two-phase state, flows into the heat exchanger 51c, and is vaporized and gasified. This refrigerant gas passes through the low-pressure gas pipe 63, a part of which passes through the second four-way valve 187 and the first suction pipe 194 to the first compressor 1, and the rest of which is the second on-off valve and the second suction pipe. Tube 1
It is sucked into the second compressor 2 via 84.

In the above description, the refrigerant discharged from the first compressor 1 is made to flow from the opening / closing valve 26a into the heat exchanger 51a which is the first condenser, and the refrigerant discharged from the second compressor 2 is made to flow from the opening / closing valve 27b to the second opening / closing valve 27b. Although it is flowing into the heat exchanger 51b which is a condenser,
As shown in FIG. 72, the first opening / closing valve 181 is opened to
The four-way valve 183 of the first discharge pipe 182 and the third connecting pipe 1
90 so that the refrigerant discharged from the first compressor 1 is the heat exchanger 51b that is the second condenser, and the refrigerant discharged from the second compressor 2 is the heat exchanger 51 that is the first condenser.
It may be allowed to flow into a. Therefore, the refrigerant from the first compressor 1 and the second compressor 2 can be introduced into the heat exchanger by switching the open / close valves according to the load states of the heat exchanger 51a and the heat exchanger 51b. Thus, in this operation mode, the heat exchanger 51a obtains the first condensation temperature, the heat exchanger 51b obtains the second condensation temperature, and the heat exchanger 51c obtains the evaporation temperature.

Next, referring to FIG. 73, two condensing temperatures and 1
The operation will be described in the case where the difference between the condensation temperature and the evaporation temperature is relatively large when three temperatures are generated to generate one evaporation temperature. This operation mode is applied, for example, during normal heating + relatively high hot water supply operation. FIG. 73 shows an example in which the heat exchanger 51a operates as a first condenser, the heat exchanger 51b operates as a second condenser, and the heat exchanger 51c operates as an evaporator. The open / close valve 184, the fourth open / close valve 191 and the open / close valves 26a, 26b, 28c are opened, and the first four-way valve 183 is connected to the first discharge pipe 182 and the high pressure gas pipe 61, and the first connecting pipe 186 and the first connection pipe 186. Three connecting tubes 190
And the second four-way valve 187 is switched so as to connect the first suction pipe 194 and the third connection pipe 190.

A part of the refrigerant gas discharged from the second compressor 2 is partly supplied to the third on-off valve 189, the second four-way valve 187 and the first
Is sucked into the first compressor 1 through the suction pipe 194, becomes high-temperature high-pressure refrigerant gas, and flows into the high-pressure gas pipe 61.
This gas refrigerant flows through the opening / closing valve 26a into the heat exchanger 51a, which is the first condenser, and is condensed and liquefied. This liquid refrigerant flows into the liquid pipe 64 through the electric expansion valve 31b.
On the other hand, the rest of the refrigerant gas discharged from the second compressor 2 is
Through the fourth on-off valve 191 and flowing into the medium pressure gas pipe 62,
The heat exchanger 51b which is the second condenser through the opening / closing valve 27b.
And is condensed and liquefied. This liquid refrigerant is an electric expansion valve 3
It flows into the liquid pipe 64 through 1b and merges with the liquid refrigerant from the heat exchanger 51a which is the first condenser. The combined liquid refrigerant flows through the electric expansion valve 31c into a low-pressure two-phase state, flows into the heat exchanger 51c, and is vaporized and gasified. This refrigerant gas passes through the low-pressure gas pipe 63 and the second opening / closing valve 185,
It is sucked into the second compressor 2 via the second suction pipe 184.

In the above description, the second compressor 2 is on the low stage side,
The operation when the first compressor 1 is on the high stage side has been described, but as shown in FIG. 74, the third opening / closing valve 189 and the first four-way valve 183 connect the first discharge pipe 182 and the second connection pipe 182. Tube 19
0, the first connecting pipe 186 and the high-pressure gas pipe 61 are communicated with each other, and the second four-way valve 187 includes the low-pressure gas pipe 63 and the first suction pipe 19.
4, the third connecting pipe 190 and the second connecting pipe 188 are switched so as to communicate with each other, and the refrigerant gas that has flowed into the heat exchanger 51c and has been vaporized and gasified is supplied from the low pressure gas pipe 63 to the second four-way valve 187. , The first compressor 1 through the first suction pipe 194, and a part of the discharge gas is sucked into the second compressor 2,
The remaining gas may be caused to flow into the medium pressure gas pipe 62 from the fifth opening / closing valve 192. Thus, in this operation mode, the heat exchanger 51a obtains the first condensation temperature, the heat exchanger 51b obtains the second condensation temperature, and the heat exchanger 51c obtains the evaporation temperature.

Next, referring to FIG. 75, one condensation temperature and 2
An operation will be described in the case where the difference between the condensation temperature and the evaporation temperature is relatively small when three temperatures are generated to generate one evaporation temperature. This operation mode is applied, for example, during normal cooling + ice heat storage operation. In FIG. 75, the heat exchanger 51a is a condenser, the heat exchanger 51b is a first evaporator, and the heat exchanger 51c.
Shows an example of operating as a second evaporator, and includes a first opening / closing valve 181, a second opening / closing valve 185, and a fifth opening / closing valve 192.
And the on-off valves 26a, 27b, 28c are opened, the first four-way valve 183 connects the first discharge pipe 182 and the high-pressure gas pipe 61, and the second four-way valve 187 connects the third connection pipe 190 and the third connection pipe 190. It is switched so that the first suction pipe 194 is communicated.

The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 passes through the first four-way valve, merges with the refrigerant discharged from the second compressor 2 via the first on-off valve 181 in the high-pressure gas pipe 61. Then, it flows into the heat exchanger 51a through the opening / closing valve 26a and is condensed and liquefied. The liquid refrigerant flows into the liquid pipe 64 through the electric expansion valve 31a, and a part of the liquid refrigerant flows through the electric expansion valve 31b into a low-pressure two-phase state, which is the heat exchanger 51b as the first evaporator. And is vaporized into gas. This refrigerant gas is
It is sucked into the first compressor 1 through the intermediate pressure gas pipe 62, the fifth opening / closing valve 192, the second four-way valve 187, and the first suction pipe 76. On the other hand, the remaining liquid refrigerant flowing into the liquid pipe 64 passes through the electric expansion valve 31c into a low-pressure two-phase state, flows into the heat exchanger 51c that is the second evaporator, and is evaporated and gasified. This gas refrigerant passes through the low pressure gas pipe 63 to the second
It is sucked into the second compressor 2 through the open / close valve 185 and the second suction pipe 184.

In the above description, the refrigerant gas in the medium pressure gas pipe 62 is sucked into the first compressor 1 and the refrigerant gas in the low pressure gas pipe 63 is sucked into the second compressor 2. However, as shown in FIG. 1 open / close valve 181, 5th open / close valve 192 and open / close valves 26a, 2
7b and 28c are opened, and the first four-way valve 183 is set to the first
The discharge pipe 182 and the high pressure gas pipe 61 are communicated with each other, and the second four-way valve 187 includes a third connecting pipe 190 and a second connecting pipe 188.
By switching the low pressure gas pipe 63 and the first suction pipe 194 so as to communicate with each other, the refrigerant gas in the medium pressure gas pipe 62 is changed to the second refrigerant gas.
The refrigerant gas in the compressor 2 and the low-pressure gas pipe 63 may be sucked into the first compressor 1. Therefore, the refrigerant can be introduced from the compressor by switching the opening / closing valve according to the heat load of the heat exchanger 51c and the heat exchanger 51b. As described above, in this operation mode, the condensation temperature in the heat exchanger 51a is
The heat exchanger 51b obtains a first evaporation temperature and the heat exchanger 51c obtains a second evaporation temperature.

Next, with reference to FIG. 77, an operation will be described in the case where the difference between the condensation temperature and the evaporation temperature is relatively large at the time of generating three temperatures for generating one condensation temperature and two evaporation temperatures. This operation mode is applied, for example, during normal cooling + ice heat storage + high-temperature hot water supply operation. 77 shows an example in which the heat exchanger 51a operates as a condenser, the heat exchanger 51b operates as a first evaporator, and the heat exchanger 51c operates as a second evaporator.
The second on-off valve 185, the third on-off valve 189, the fifth on-off valve 192 and the on-off valves 26a, 27b, 28c are opened, and the first four-way valve 183 is connected to the first discharge pipe 182 and the high pressure gas pipe. 61, the first connecting pipe 186 and the third connecting pipe 190 are communicated with each other, and the second four-way valve 187 is switched so as to communicate the third connecting pipe 190 and the first suction pipe 194.

The high-temperature high-pressure refrigerant gas discharged from the first compressor 1 flows into the high-pressure gas pipe 61 from the first four-way valve 183, passes through the on-off valve 26a and flows into the heat exchanger 51a, and is condensed and liquefied. . The liquid refrigerant flows into the liquid pipe 64 through the electric expansion valve 31a, and a part of the liquid refrigerant flows through the electric expansion valve 31b into a low-pressure two-phase state, which is the heat exchanger 51b as the first evaporator. And is vaporized into gas. This refrigerant gas is
The second through the fifth on-off valve 192 through the medium pressure gas pipe 62
It joins the discharge gas of the compressor 2 and is sucked into the first compressor 1 via the second four-way valve 187 and the first suction pipe 194. On the other hand, the remaining liquid refrigerant flowing into the liquid pipe 64 is the electric expansion valve 3
After passing through 1c, it becomes a low-pressure two-phase state and flows into the heat exchanger 51c which is the second evaporator, and is vaporized and gasified. The gas refrigerant is sucked into the second compressor 2 through the low pressure gas pipe 63, the second opening / closing valve 185 and the second suction pipe 184.

In the above description, the second compressor 2 is on the low stage side,
The operation when the first compressor 1 is on the high stage side has been described, but as shown in FIG. 78, the first on-off valve 181 and the third on-off valve 181 are provided.
The open / close valve 189 and the fifth open / close valve 192 of FIG. The communication, the second four-way valve 187 is switched so that the low-pressure gas pipe 63 and the first suction pipe 194 and the third connection pipe 190 and the second connection pipe 188 communicate with each other, so that the heat exchanger 51c
The refrigerant gas that has flowed into the chamber and has been vaporized and gasified is passed through the low pressure gas pipe 63, the second four-way valve 187, and the first suction pipe 194, and
The gas is sucked into the compressor 1, and its discharge gas and the fifth on-off valve 19
2 and a part of the refrigerant in the medium pressure gas pipe 62 from the second compressor 2
Alternatively, the discharge gas may be sucked into the high pressure gas pipe 61 through the first opening / closing valve 181. in this way,
In this operation mode, the heat exchanger 51a obtains the condensation temperature, the heat exchanger 51b obtains the first evaporation temperature, and the heat exchanger 51c obtains the second evaporation temperature. In Examples 9 to 11, the low-stage compressor and the high-stage compressor can be selected according to the load, so that the circuit has sufficient performance for a wide range of operation.

Example 12. Example 12 will be described with reference to FIG. 79. In the figure, 1 is a first compressor, 2 is a second compressor, 11 is a first accumulator, 12 is a second accumulator, 51a, 51b and 51c are heat exchangers, and 57 is a hot water heat exchanger. 61 is a first pipe which is a high pressure gas pipe connected to the discharge side of the first compressor 1, and 62 is a second compressor 2
The second pipe, which is a medium-pressure gas pipe connected to the discharge side of the first via the first opening / closing valve 21 that is the first switch, 63 is connected to the first compressor 1 via the first accumulator 11 on the suction side. A third pipe, which is a low-pressure gas pipe connected, 64 is a liquid pipe. Third pipe 6 between the first compressor 1 and the first accumulator 11
A second on-off valve and a first check valve 4 which constitute a third switch are provided at 3.
1 is provided. Reference numeral 23 is a third opening / closing valve of the fifth opening / closing valve provided in the high-pressure gas communication pipe 65 connecting the second pipe 62 and the first pipe 61 between the second compressor 2 and the first opening / closing valve 21, and 24 is A high pressure gas communication pipe 65 between the second compressor 2 and the third on-off valve 23 and a compressor communication pipe 66 connecting the third pipe 63 between the second on-off valve 22 and the first check valve 41. The fourth on-off valve provided, and in this case, the fourth on-off valve is composed of the second on-off valve, the fourth on-off valve and the first check valve. 25
Second pipe 6 that branches to connect to the suction side of the first compressor 1.
Second pipe 62 between the second branch point and the second accumulator 12
Is a fifth opening / closing valve, and 42 is a second opening / closing valve provided in the second pipe 62 between the first compressor 1 and the second accumulator 12.
It is a check valve, and the second switch is the fifth switch valve 25 and the second check valve 4.
It is composed of two. The first pipe is connected to the heat exchanger 51a via the first switching four-way valve 271 and the third switching four-way valve 273, and the third pipe is connected to the heat exchanger 51b by the first switching four-way valve 27.
The second pipe has a second switching four-way valve 272 and a third switching four-way valve 2 in the heat exchanger 51c via the first and second switching four-way valves 272.
The liquid pipe 64 is connected via the electronic expansion valves 31a, 31b, 31c which are refrigerant flow rate controllers. The hot water supply heat exchanger 57 is branched from the first pipe, and the liquid pipe 64 is connected to the hot water heat exchanger 57 via an electronic expansion valve 31d which is a refrigerant flow rate controller.

The cooling and heating heat storage hot water supply system of this embodiment has six operation modes as shown in Table 1. The six operation modes will be described below with reference to FIGS.

First, using the explanatory diagram showing the operating state of the cooling and heating heat storage and hot water supply system of FIG. 80, the difference between the condensation temperature and the evaporation temperature at the time of generating two temperatures for generating one condensation temperature and one evaporation temperature The operation when the size is relatively small will be described. This operation mode is applied, for example, during normal cooling or heating. 80 shows an example in which the heat exchanger 51a operates as a condenser, the heat exchanger 51b operates as an evaporator, and the heat exchangers 51c and 57 stop. The first on-off valve 21,
The fourth opening / closing valve 24 and the fifth opening / closing valve 25 are closed (filled in the figure). The first switching four-way valve 271, the second switching four-way valve 272, and the third switching four-way valve 273 are all in the non-energized state. The first compressor 1 and the second compressor 2 are operated in parallel. The arrow indicates the flow of the refrigerant. The high-temperature high-pressure refrigerant gas discharged from the second compressor 2 merges with the high-temperature high-pressure refrigerant gas discharged from the first compressor 1 in the first pipe 61 via the high-pressure gas communication pipe 65, and the first switching four-way valve 271, It flows into the heat exchanger 51a through the third switching four-way valve 273 and is condensed and liquefied. This liquid refrigerant passes through the electric expansion valve 31a and the liquid pipe 6
4 into the heat exchanger 51b in the low pressure two-phase state through the electronic expansion valve 31b, and is vaporized into gas. This gas refrigerant is drawn into the first compressor 1 and the second compressor 2 through the third pipe 63 and the first accumulator 11. Thus, in this operation mode, the heat exchanger 51a obtains the condensation temperature and the heat exchanger 51b obtains the evaporation temperature.

[0210] Next, one condensing temperature and 1
An operation will be described in the case where a difference between the condensation temperature and the evaporation temperature is relatively large when two temperatures are generated to generate one evaporation temperature. This operation mode is applied, for example, to hot water supply or hot water supply + ice heat storage. In FIG. 81, the heat exchanger 57d is a condenser, the heat exchanger 51b is an evaporator, and the heat exchangers 51a and 51b.
The example in which c operates as a stop is shown, and the first on-off valve 2
The first, third on-off valve 23, and fifth on-off valve 25 are closed (filled in the figure). The first switching four-way valve 71, the second switching four-way valve 272, and the third switching four-way valve 273 are all in the non-energized state. The first compressor 1 and the second compressor 2 are operated in series. The arrow indicates the flow of the refrigerant.

The high-temperature high-pressure refrigerant gas discharged from the second compressor flows into the high-pressure gas communication pipe 65 and the compressor communication pipe 66 branched from the high-pressure gas communication pipe 65, and the fourth on-off valve 24 and the second on-off valve 22.
The refrigerant gas is sucked into the first compressor 1 through the passage, is compressed in two stages, and becomes a high-temperature and high-pressure refrigerant gas, and flows into the first pipe 61. This gas refrigerant flows into the heat exchanger 51a through the first pipe 61 and is condensed and liquefied. This liquid refrigerant is used in the electronic expansion valve 31.
through a, into the liquid pipe 64, and through the electronic expansion valve 31b into a low-pressure two-phase state and into the heat exchanger 51b,
Evaporative gasification. This gas refrigerant is drawn into the second compressor 2 through the third pipe 63, the first accumulator 11, and the second compressor 2. As described above, in this operation mode, the two-stage compression operation is performed, and the condensation temperature in the heat exchanger 51a is
The evaporation temperature is obtained in b.

Next, referring to FIG. 82, which is an explanatory view showing the operating state of the cooling and heating heat storage and hot water supply system of this embodiment, at the time of generating three temperatures for generating two condensation temperatures and one evaporation temperature,
The operation when the difference between the condensation temperature and the evaporation temperature is relatively small will be described. This operation mode is, for example, normal heating +
It is applied when operating a relatively low hot water supply. In FIG. 82,
In the example, the heat exchanger 57 operates as a first condenser, the heat exchanger 51b operates as a second condenser, the heat exchanger 51a operates as an evaporator, and the heat exchanger 51c stops. The 4th on-off valve 24 and the 5th on-off valve 25 are in a closed state (filled in the figure). The first switching four-way valve 271 and the second switching four-way valve 272 are in the energized state (circuit switching state), and the third switching four-way valve 273 is in the non-energized state. The first compressor 1 and the second compressor 2 are operated in parallel. The arrow indicates the flow of the refrigerant.

The high-temperature high-pressure refrigerant gas discharged from the first compressor flows into the first pipe 61 and the heat exchanger 51d, which is the first condenser, and is condensed and liquefied. This liquid refrigerant flows into the liquid pipe 64 through the electronic expansion valve 31d. on the other hand,
The high-temperature high-pressure refrigerant gas discharged from the second compressor 2 is
It flows into the second pipe 62 through the on-off valve 21, passes through the second switching four-way valve 272, flows into the heat exchanger 51b that is the second condenser, and is condensed and liquefied. This liquid refrigerant is used in the electronic expansion valve 3
It flows into the liquid pipe 64 through 1b, and joins with the liquid refrigerant from the heat exchanger 57 which is the first condenser. The combined liquid refrigerant flows through the electronic expansion valve 31a into a low-pressure two-phase state, flows into the heat exchanger 51a, and is vaporized and gasified. This gas refrigerant passes through the third pipe 63 and the first accumulator 1
1 and is sucked into the first compressor 1 and the second compressor 2. Thus, in this operation mode, the heat exchanger 57 obtains the first condensation temperature, the heat exchanger 51b obtains the second condensation temperature, and the heat exchanger 51a obtains the evaporation temperature.

Next, referring to the explanatory view showing the operation state of the cooling and heating heat storage and hot water supply system of this embodiment in FIG. 83, when three temperatures are generated to generate two condensation temperatures and one evaporation temperature, The operation when the difference in evaporation temperature is relatively large will be described. This operation mode is applied, for example, during normal heating + relatively high hot water supply operation. In FIG. 83, the heat exchanger 57 is the first condenser and the heat exchanger 51b is the second condenser.
An example in which the condenser and the heat exchanger 51a operate with the evaporator and the heat exchanger 51c stopped is shown, and the third opening / closing valve 23 and the fifth opening / closing valve 25 are closed (filled in the figure). The first switching four-way valve 271 and the second switching four-way valve 272 are in the energized state (circuit switching state), and the third switching four-way valve 273 is in the non-energized state. The first compressor 1 and the second compressor 2 are operated in series. The arrow indicates the flow of the refrigerant.

A part of the refrigerant gas discharged from the second compressor 2 flows into the compressor communication pipe 66, and is sucked into the first compressor 1 through the fourth opening / closing valve 24 and the second opening / closing valve 22. , Is compressed in two stages, becomes high-temperature high-pressure refrigerant gas, and flows into the first pipe 61. This gas refrigerant flows into the heat exchanger 51d, which is the first condenser, and is condensed and liquefied. This liquid refrigerant flows into the liquid pipe 64 through the electronic expansion valve 31d. On the other hand, the rest of the refrigerant gas discharged from the second compressor 2 flows into the second pipe 62 through the first opening / closing valve 21, and the second switching four-way valve 2
After passing through 72, it flows into the heat exchanger 51b which is the second condenser, and is condensed and liquefied. This liquid refrigerant is an electronic expansion valve 31b.
To flow into the liquid pipe 64 and join the liquid refrigerant from the heat exchanger 57, which is the first condenser. This combined liquid refrigerant is
It passes through the electronic expansion valve 31a, becomes a low-pressure two-phase state, flows into the heat exchanger 51a, and is vaporized and gasified. The gas refrigerant passes through the third pipe 63, passes through the first accumulator 11, and is sucked into the second compressor 2. Thus, in this operation mode, the heat exchanger 57 obtains the first condensation temperature, the heat exchanger 51b obtains the second condensation temperature, and the heat exchanger 51a obtains the evaporation temperature.

[0216] Next, using the explanatory diagram showing the operating state of the cooling / heating heat storage / hot water supply system in Fig. 84, one condensing temperature and 2
The operation when the difference between the condensation temperature and the evaporation temperature is relatively small when the three evaporation temperatures are generated will be described. This operation mode is applied, for example, during normal cooling + ice heat storage operation. FIG. 84 shows an example in which the heat exchanger 51a operates as a condenser, the heat exchanger 51b operates as a first evaporator, the heat exchanger 51c operates as a second evaporator, and the heat exchanger 57 stops. The valve 21, the second opening / closing valve 22, and the fourth opening / closing valve 24 are closed (filled in the figure). First
The switching four-way valve 271, the second switching four-way valve 272, and the third switching four-way valve 273 are not energized. The first compressor 1 and the second compressor 2 are operated in parallel. The arrow indicates the flow of the refrigerant.

The high-temperature and high-pressure refrigerant gas discharged from the first compressor 1 passes through the third on-off valve 23 and the high-pressure gas communication pipe 265.
Through which the discharge refrigerant gas of the second compressor 2 merges in the first pipe 61, and the first switching four-way valve 271 and the third switching four-way valve 273.
Through which it flows into the heat exchanger 51a and is condensed and liquefied. The liquid refrigerant flows into the liquid pipe 64 through the electronic expansion valve 31a, and a part of the liquid refrigerant flows through the electronic expansion valve 31b into a low-pressure two-phase state, which is the first evaporator heat exchanger 51b. And is vaporized into gas. This gas refrigerant is drawn into the first compressor 1 through the second pipe 62, the fifth opening / closing valve 25, the second accumulator 12, and the second check valve. On the other hand, the liquid pipe 6
The remaining liquid refrigerant flowing into No. 4 passes through the electronic expansion valve 31c to become a low-pressure two-phase state and is the second evaporator. It flows into the heat exchanger 51c and is vaporized and gasified. The gas refrigerant passes through the third pipe 63, passes through the first accumulator 11, and is sucked into the second compressor 2. Thus, in this operation mode, the condensation temperature in the heat exchanger 51a is
The first evaporation temperature is obtained at 1b, and the second evaporation temperature is obtained at the heat exchanger 51c.

Next, using the explanatory diagram showing the operating state of the cooling and heating heat storage hot water supply system of FIG. 85, the difference between the condensation temperature and the evaporation temperature is generated at the time of generating three temperatures for generating one condensation temperature and two evaporation temperatures. The operation when is relatively large will be described. This operation mode is applied, for example, during cooling + ice heat storage + high-temperature hot water supply operation. In FIG. 85, the heat exchanger 57 is a condenser, the heat exchanger 51b is a first evaporator, and the heat exchanger 51c.
Shows an example in which the second evaporator and the heat exchanger 51a operate as stopped, and the third opening / closing valve 23 and the fifth opening / closing valve 25 are in a closed state (filled in the figure). Second switching four-way valve 2
72 is an energized state (switching state), a first switching four-way valve 271,
The third switching four-way valve 273 is in a non-energized state. The first compressor 1 and the second compressor 2 are operated in series. The arrow indicates the flow of the refrigerant.

The high-temperature and high-pressure refrigerant gas discharged from the first compressor 1 flows into the heat exchanger 57 via the first pipe 61,
Condensed and liquefied. The liquid refrigerant flows into the liquid pipe 64 through the electronic expansion valve 31a, and a part of the liquid refrigerant flows into the electronic expansion valve 31a.
After passing through b, a low-pressure two-phase state is established, which flows into the heat exchanger 51b, which is the first evaporator, and evaporates and gasifies. This gas refrigerant merges with the discharge gas of the second compressor 2 through the first opening / closing valve 21 through the second pipe 62, passes through the fourth opening / closing valve 24 and the second opening / closing valve 22, and then passes through the first compressor 1 Inhaled into. On the other hand, the remaining liquid refrigerant that has flowed into the liquid pipe 64 passes through the electronic expansion valve 31c and becomes a low-pressure two-phase state, which is the second evaporator. It flows into the heat exchanger 51c and is vaporized and gasified. The gas refrigerant passes through the third pipe 63, passes through the first accumulator 11, and is sucked into the second compressor 2. Thus, in this operation mode, the condensation temperature in the heat exchanger 51a is
The first evaporation temperature is obtained at 1b, and the second evaporation temperature is obtained at the heat exchanger 51c.

As described above, in this embodiment, the above 6
Three saturation temperatures can be set for each heat exchanger according to one operation mode and functions required for each heat exchanger such as cooling and heating, hot water supply, and ice heat storage. Further, when the difference between the condensation temperature and the evaporation temperature is small or large, the first and second compressors are operated individually or in parallel, or in series (two-stage compression operation).
It can be used properly and a highly efficient cycle can be realized. Furthermore, when cooling and ice heat storage and heating and hot water supply are operated at the same time, the waste heat of cooling and ice storage can be used for heating and hot water supply, so that a more efficient cycle can be realized. Further, since the high pressure gas communication pipe is provided, the discharge gas of the second compressor can be added to the discharge gas of the first compressor to improve the condensation or evaporation ability. Since the accumulators are provided on the suction sides of the first and second compressors, it is possible to prevent the liquid from returning to the compressor at the time of starting or switching the operation modes, protect the compressor, and adjust the amount of refrigerant. Also, by using a four-way valve, the number of valves can be greatly reduced and the unit can be made compact.

The multi-temperature generation circuits by the vapor compression refrigeration cycle of the sixth to twelfth embodiments of the present invention have the following effects. The multi-temperature generation circuit by the vapor compression refrigeration cycle of the present invention has a first compressor, a second compressor, a plurality of heat exchangers, one end on the discharge side of the first compressor, and the other end. A high-pressure gas pipe connected to the plurality of heat exchangers via an on-off valve, one end to the discharge side of the second compressor via the first on-off valve, and the other end to the multiple units via an on-off valve Medium pressure gas that is connected to the heat exchanger of the first compressor and branches from between the first on-off valve and the on-off valve to connect to the suction side of the first compressor via the fifth on-off valve and the second check valve. A tube and one end is the second
The first check valve and the second check valve are connected to the suction side of the compressor.
A low-pressure gas pipe connected to the suction side of the first compressor through an on-off valve in this order, and the other end connected to the plurality of heat exchangers through an on-off valve, and the plurality of heat exchangers. A liquid pipe connected via a refrigerant flow controller, a high pressure gas communication pipe connecting the discharge side of the first compressor and the discharge side of the second compressor via a third opening / closing valve, and the second A compressor communication pipe that connects the discharge side of the compressor to the first check valve and the second open / close valve via a fourth open / close valve, and the liquid from the intermediate pressure gas pipe via a seventh open / close valve. Since the first bypass passage leading to the pipe and the second bypass passage leading from the liquid pipe to the suction side of the first compressor via the eighth opening / closing valve are provided, the condensation temperature and the evaporation are reduced. In case of high temperature hot water supply / heating simultaneous operation or ice heat storage / hot water simultaneous operation with relatively large temperature difference and relatively large compression ratio, After cooling the discharged gas through the liquid pipe through the on-off valve, and then performing the two-stage compression operation in which it is sucked into the high-stage compressor, the discharge temperature rise is prevented and two condensation temperatures and one evaporation The temperature can be obtained efficiently. In the case of simultaneous ice cold storage / cooling / hot water supply operation where the difference between the condensation temperature and the evaporation temperature is relatively large and the compression ratio is relatively large, the discharge gas of the low-stage compressor is passed from the liquid pipe through the on-off valve. By performing multi-stage compression operation in which the bypassed liquid is combined and cooled, and then sucked into the high-stage compressor, discharge temperature rise is prevented and one condensation temperature and two evaporation temperatures can be obtained efficiently. .

The multi-temperature generation circuit according to the vapor compression refrigeration cycle of the present invention has a first compressor, a second compressor, a plurality of heat exchangers, and one end on the discharge side of the first compressor. A high pressure gas pipe having the other end connected to the plurality of heat exchangers via an on-off valve, one end on the discharge side of the second compression via the first on-off valve, and the other end via the on-off valve. It is connected to the plurality of heat exchangers and branches from between the first on-off valve and the on-off valve to branch through the fifth on-off valve and the second check valve to the first
A medium-pressure gas pipe connected to the suction side of the compressor, one end of which is connected to the suction side of the second compressor, and a first check valve and a second opening / closing valve in this order to suction the first compressor. A low-pressure gas pipe connected to the side, the other end is connected to the plurality of heat exchangers via an on-off valve, and a liquid pipe connected via a refrigerant flow rate controller of the plurality of heat exchangers, A high-pressure gas communication pipe that connects the discharge side of the first compressor and the discharge side of the second compressor via a third on-off valve, the discharge side of the second compressor, the first check valve, and the second A compressor communication pipe that connects between the on-off valves via a fourth on-off valve, a first bypass path from the medium-pressure gas pipe to the liquid pipe via a refrigerant flow controller, and a liquid pipe from the liquid pipe The second bypass passage leading to the suction side of the first compressor via the eight opening / closing valve is provided. Is relatively large, and the compression ratio is relatively large, in the case of high-temperature hot water supply / heating simultaneous operation, the gas discharged from the low-stage compressor is cooled by passing it through the liquid pipe through the expansion valve and then sucked into the high-stage compressor. By performing the multi-stage compression operation, it is possible to prevent the discharge temperature from rising and at the same time obtain a higher hot water supply pressure by optimally controlling the bypass amount to the higher stage side, and at the same time secure the heating capacity, Moreover, two condensation temperatures and one evaporation temperature can be efficiently obtained. In addition, in the case of simultaneous ice cold storage / cooling / hot water supply operation where the difference between the condensation temperature and the evaporation temperature is relatively large and the compression ratio is relatively large, the discharge gas of the low-stage compressor is fed from the liquid pipe to the expansion valve. After cooling by combining with the liquid that has been bypassed via the high-stage compressor, the multi-stage compression operation is performed to suck it into the high-stage compressor to prevent the discharge temperature from rising and at the same time optimally control the liquid bypass amount It is possible to obtain a higher condensation temperature while preventing liquid compression of the compressor, and to efficiently obtain one condensation temperature and two evaporation temperatures.

The multi-temperature generation circuit according to the vapor compression refrigeration cycle of the present invention has a first compressor, a second compressor, a plurality of heat exchangers, and one end on the discharge side of the first compressor. A high-pressure gas pipe having the other end connected to the plurality of heat exchangers via an on-off valve, one end on the discharge side of the second compressor via the first on-off valve, and the other end via the on-off valve. It is connected to the plurality of heat exchangers and branches from between the first on-off valve and the on-off valve to branch through the fifth on-off valve and the second check valve to the first
A medium-pressure gas pipe connected to the suction side of the compressor, one end of which is connected to the suction side of the second compressor, and a first check valve and a second opening / closing valve in this order to suck the first compressor. A low pressure gas pipe connected to the side, the other end is connected to the plurality of heat exchangers via an on-off valve, a liquid receiver connected to the plurality of heat exchangers via a refrigerant flow controller, A high-pressure gas communication pipe that connects the discharge side of the first compressor and the discharge side of the second compressor via a third opening / closing valve, the discharge side of the second compressor, the first check valve, and the second check valve. The compressor communication pipe that connects the on-off valves via the fourth on-off valve and the medium-pressure gas pipe to the seventh pipe.
In a configuration including a first bypass passage leading to the liquid receiver via an on-off valve, and a second bypass passage extending from the liquid receiver to the suction side of the first compressor via an eighth on-off valve. Therefore, in the case of high temperature hot water supply / heating simultaneous operation or ice heat storage / hot water simultaneous operation where the difference between the condensation temperature and the evaporation temperature is relatively large and the compression ratio is relatively large, the discharge gas of the low-stage compressor is passed through the on-off valve. While performing cooling and gas-liquid separation at the same time through the liquid receiver and performing a multi-stage compression operation in which the high-stage compressor sucks, discharge temperature rise and liquid compression of the high-stage compressor are prevented. It is possible to obtain a higher condensation temperature, and efficiently obtain two condensation temperatures and one evaporation temperature. Also, in the case of simultaneous ice cold storage / cooling / hot water supply operation where the difference between the condensation temperature and the evaporation temperature is relatively large and the compression ratio is relatively large, the discharge gas of the low-stage compressor should be opened / closed from the liquid receiver. It is possible to prevent the discharge temperature from rising and to obtain a higher condensing temperature by performing a multi-stage compression operation in which the liquid bypassed via the cooling is combined and cooled and then sucked into the high-stage compressor. One condensation temperature and two evaporation temperatures can be efficiently obtained.

The multi-temperature generation circuit according to the vapor compression refrigeration cycle of the present invention has a first compressor, a second compressor, a plurality of heat exchangers, and a first open / close valve at one end. On the discharge side of the first compressor via a discharge pipe, the other end has a high pressure gas pipe connected to the plurality of heat exchangers via an open / close valve, and the second end has a second open / close valve. On the discharge side of the second compressor via a discharge pipe, the other end is a medium pressure gas pipe connected to the plurality of heat exchangers via an on-off valve, and one end is a fourth
A low-pressure gas pipe connected to the plurality of heat exchangers via the on-off valve on the suction side of the second compressor via a second suction pipe having the on-off valve, and A liquid pipe connected to the heat exchanger via a refrigerant flow controller; a first suction pipe connecting the medium-pressure gas pipe to the suction side of the first compressor via a third opening / closing valve; A discharge-side connecting pipe that connects the first discharge pipe and the second discharge pipe via a seventh opening / closing valve and an eighth opening / closing valve, and the first suction pipe and the second suction pipe. A suction side connecting pipe connected via a ninth opening / closing valve and a tenth opening / closing valve, and a first bypass connecting the intermediate pressure gas pipe and the second suction pipe via a fifth opening / closing valve. With a tube,
A second bypass pipe connecting the low-pressure pipe and the first suction pipe via a sixth opening / closing valve, between the seventh opening / closing valve, the eighth opening / closing valve, and the ninth opening / closing valve, A third bypass pipe connecting between the 10 open / close valves via an 11th open / close valve;
A fourth bypass pipe connecting the second discharge pipe and the high-pressure gas pipe via a thirteenth on-off valve, a first discharge pipe and the medium-pressure gas pipe and a twelfth on-off valve. Since the fifth bypass pipe connected via the heat exchanger is provided, the number of the heat exchangers is 3 or less depending on the function required for each heat exchanger such as cooling and heating, hot water supply, and ice heat storage. Saturation temperature can be set. In addition, when the difference between the condensation temperature and the evaporation temperature is small or large, and when the operation of multiple compressors with different capacities depending on the size of the load is used properly, it is possible to secure the capacity suitable for the load and perform multi-stage compression operation. A highly efficient refrigerant circuit can be realized. Furthermore, when cooling or ice heat storage and heating or hot water supply are operated at the same time, the waste heat of the cooling or ice heat storage can be used for heating or hot water supply, so that effective use of energy can be achieved. It is a thing.

The multi-temperature generation circuit according to the vapor compression refrigeration cycle of the present invention includes a first compressor, a second compressor, a plurality of heat exchangers, a four-way valve, and a first opening / closing valve at one end. A high pressure gas pipe having the other end connected to the plurality of heat exchangers via an on-off valve and a second on-off valve at one end are provided on the discharge side of the first compressor via the first discharge pipe. The other end is connected to the plurality of heat exchangers via an on-off valve on the discharge side of the second compressor via the second discharge pipe, and is branched from the middle to be connected to the four-way valve. A medium-pressure gas pipe, one end to the four-way valve, the other end to a low-pressure gas pipe connected to the plurality of heat exchangers via an on-off valve, and the plurality of heat exchangers via a refrigerant flow controller First suction pipe for connecting the four-way valve and the suction side of the first compressor via a third on-off valve A second suction pipe connecting the four-way valve and a suction side of the second compressor via a fourth opening / closing valve, and a seventh opening / closing of the first discharge pipe and the second discharge pipe. A discharge side connecting pipe connected through the valve and the eighth opening / closing valve,
Between the suction side connecting pipe that connects the first suction pipe and the second suction pipe via the ninth opening / closing valve and the tenth opening / closing valve, and the seventh opening / closing valve and the eighth opening / closing valve. And a third bypass pipe connecting between the ninth on-off valve and the tenth on-off valve via an eleventh on-off valve, and the second discharge pipe and the high-pressure gas pipe on a thirteenth open / close A fourth bypass pipe connected via a valve, the first discharge pipe and the medium pressure gas pipe to the first
Since the fifth bypass pipe connected through the on-off valve 2 is provided, each heat exchanger is provided with a function of each heat exchanger such as cooling / heating, hot water supply, and ice storage. Up to 3 saturation temperatures can be set. In addition, when the difference between the condensation temperature and the evaporation temperature is small or large, and when the operation of multiple compressors with different capacities depending on the size of the load is used properly, it is possible to secure the capacity suitable for the load and perform multi-stage compression operation. A highly efficient refrigerant circuit can be realized. Furthermore,
When cooling and ice heat storage and heating and hot water supply are operated at the same time,
Since the waste heat of cooling and ice storage can be used for heating and hot water supply, it has a great effect such as effective use of energy.

The multi-temperature generation circuit according to the vapor compression refrigeration cycle of the present invention comprises a first compressor, a second compressor, a plurality of heat exchangers, a first four-way valve, and a second four-way valve. And one end is connected to the discharge side of the first compressor via a first discharge pipe to which the first four-way valve is connected, and the other end is connected to the plurality of heat exchangers via an on-off valve. When the high-pressure gas pipe and the other end are connected to the plurality of heat exchangers via the on-off valve, the medium-pressure gas pipe and one end is connected to the suction side of the second compressor via the second on-off valve. A low-pressure gas pipe having the other end connected to the plurality of heat exchangers via an on-off valve, and a liquid pipe connected to the plurality of heat exchangers via a refrigerant flow controller to the second suction pipe. A first suction pipe connecting the low-pressure gas pipe and the first compressor via the second four-way valve, and a discharge side and a front of the second compressor. A first connecting pipe connecting between the first on-off valve and the first four-way valve, between the suction side of the second compressor and the second on-off valve, and the second four-way A second connecting pipe connecting the valve and a third connecting pipe connecting the first four-way valve and the second four-way valve via a third opening / closing valve;
A fourth connecting pipe and a fifth connecting pipe branching from both sides of the third on-off valve and connected to one end of the medium-pressure gas pipe through a fourth on-off valve and a fifth on-off valve, respectively. Since the configuration is provided, three or less saturation temperatures can be set for each heat exchanger according to the functions required for each heat exchanger such as cooling and heating, hot water supply, and ice heat storage. In addition, when the difference between the condensation temperature and the evaporation temperature is small or large, and when the operation of multiple compressors with different capacities depending on the size of the load is used properly, it is possible to secure the capacity suitable for the load and perform multi-stage compression operation. A highly efficient refrigerant circuit can be realized. Furthermore, when cooling and ice heat storage and heating and hot water supply are operated at the same time, the waste heat of cooling and ice storage can be used for heating and hot water supply.
It has a great effect such as effective use of energy.

The multi-temperature generation circuit according to the vapor compression refrigeration cycle of the present invention includes a first compressor, a second compressor, a hot water heat exchanger and a plurality of heat exchangers, and a first four-way valve. ,
A second four-way valve, a third four-way valve, one end on the discharge side of the first compressor, and the other end on the hot water supply heat exchanger and the first
Four-way valve, a high-pressure gas pipe connected to the plurality of heat exchangers via a third four-way valve, one end to the discharge side of the second compressor via the first opening / closing valve, and the other end to the first Medium pressure connected to the plurality of heat exchangers via the second four-way valve and the third four-way valve, and branched in the middle to connect to the suction side of the first compressor via the fifth on-off valve. The gas pipe, one end of which is connected to the suction side of the second compressor, the first check valve and the second opening / closing valve are connected in this order to the suction side of the first compressor, and the other end of which is the first Low-pressure gas pipe connected to the plurality of heat exchangers via a four-way valve and a second four-way valve, and connected to the hot water supply heat exchanger and the plurality of heat exchangers via a refrigerant flow controller Liquid pipe, a high pressure gas communication pipe connecting the discharge side of the first compressor and the discharge side of the second compressor via a third opening / closing valve, and the second pressure Wherein a discharge side of the machine the first check valve and the second
The compressor communication pipe that connects between the on-off valves via the fourth on-off valve is provided, so that each of the heat exchangers such as cooling and heating, hot water supply, and ice heat storage has a function depending on the function required. Three or more saturation temperatures can be set for each heat exchanger. In addition, when the difference between the condensation temperature and the evaporation temperature is small or large, a highly efficient cycle can be realized by selectively operating the plurality of compressors. Further, when cooling or ice heat storage and heating or hot water supply are operated at the same time, waste heat of cooling or ice heat storage can be used for heating or hot water supply, so that energy can be effectively used.

[0228]

According to the present invention, since the vapor compression refrigeration cycle is constituted by the gas pipes which are more than the number of compressors and the liquid pipe common to the heat exchangers connected to the compressors, a large number of gas pipes are provided for each heat exchanger. Since the saturation temperature of can be set at the same time and the desired configuration can be freely selected, it can be applied to any condition with the standard configuration product and modification such as specification change is easy, and the temperature condition can be used to the maximum extent. It is possible to obtain a highly efficient cycle with a wide operating range, such as heat recovery and heat recovery.

Further, since it is possible to efficiently obtain a plurality of temperatures at the same time, for example, heating and hot water supply can be performed at the same time without lowering the performance of either.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a refrigerant system of a multi-temperature generation circuit according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of a driving operation state when generating two temperatures in which the difference between the condensation temperature and the evaporation temperature of the multi-temperature generation circuit according to the first embodiment of the present invention is relatively small.

FIG. 3 is an operation operation state explanatory diagram when generating two temperatures in which the difference between the condensation temperature and the evaporation temperature of the multi-temperature generation circuit according to the first embodiment of the present invention is relatively large.

FIG. 4 is an operation operation state explanatory diagram when three temperatures are generated in the multi-temperature generation circuit according to the first embodiment of the present invention, in which a difference between two condensation temperatures and one evaporation temperature is relatively small.

FIG. 5 is an operation operation state explanatory diagram when three temperatures are generated in the multi-temperature generation circuit according to the first embodiment of the present invention, in which a difference between two condensation temperatures and one evaporation temperature is relatively large.

FIG. 6 is an explanatory diagram of a driving operation state when three temperatures are generated in the multi-temperature generation circuit according to the first embodiment of the present invention when a difference between one condensation temperature and two evaporation temperatures is relatively small.

FIG. 7 is an explanatory diagram of a driving operation state when three temperatures are generated in the multi-temperature generation circuit according to the first embodiment of the present invention when the difference between one condensation temperature and two evaporation temperatures is relatively large.

FIG. 8 is a configuration diagram of a refrigerant system of a multi-temperature generation circuit according to a second embodiment of the present invention.

FIG. 9 is a configuration diagram of a multi-temperature generation circuit according to a third embodiment of the present invention.

FIG. 10 is an explanatory diagram of an operating state at the time of a 3-condensing 1-evaporating operation according to the third embodiment of the present invention.

FIG. 11 is an operation state explanatory diagram at the time of the two-condensation / two-evaporation operation of the third embodiment of the present invention.

FIG. 12 is a configuration diagram of a multi-temperature generation circuit according to a fourth embodiment of the present invention.

FIG. 13 is an explanatory view of the operating state during the two-condensing and one-evaporating operation according to the fourth embodiment of the present invention.

FIG. 14 is a configuration diagram of a multi-temperature generation circuit according to a fifth embodiment of the present invention.

FIG. 15 is an operation state explanatory diagram during a cooling operation according to the fifth embodiment of the present invention.

[Fig. 16] Fig. 16 is an operation state explanatory view during heating operation according to the fifth embodiment of the present invention.

FIG. 17 is an explanatory diagram of an operating state during a hot water supply operation according to the fifth embodiment of the present invention.

[Fig. 18] Fig. 18 is an operation state explanatory diagram at the time of cooling hot water supply operation according to the fifth embodiment of the present invention.

[Fig. 19] Fig. 19 is an explanatory view of the operating state during the heating and hot water supply operation according to the fifth embodiment of the present invention.

FIG. 20 is an operation state explanatory diagram at the time of the additional heating operation according to the fifth embodiment of the present invention.

[Fig. 21] Fig. 21 is an operation state explanatory diagram at the time of rapid hot water replenishment operation using hot water supply in Embodiment 5 of the present invention.

[Fig. 22] Fig. 22 is an operation state explanatory diagram at the time of heating additional heating according to the fifth embodiment of the present invention.

FIG. 23 is an explanatory diagram of an operating state at the time of the residual hot water heat recovery hot water supply operation according to the fifth embodiment of the present invention.

FIG. 24 is an operation state explanatory diagram during hot water supply-use defrost heating operation according to the fifth embodiment of the present invention.

FIG. 25 is a configuration diagram of a refrigerant system of a multi-temperature generation circuit by a vapor compression refrigeration cycle according to Embodiment 6 of the present invention.

[Fig. 26] Fig. 26 is a diagram showing the operating state during two-temperature generation when the difference between the condensation temperature and the evaporation temperature is relatively small in the multi-temperature generation circuit by the vapor compression refrigeration cycle according to the sixth embodiment of the present invention.

FIG. 27 is a diagram showing the operating state during two-temperature generation when the difference between the condensation temperature and the evaporation temperature is relatively large in the multi-temperature generation circuit by the vapor compression refrigeration cycle according to the sixth embodiment of the present invention.

FIG. 28 is a diagram showing an operating state of operation when generating three temperatures when the difference between two condensation temperatures and one evaporation temperature is relatively small in the multi-temperature generation circuit by the vapor compression refrigeration cycle according to Embodiment 6 of the present invention. Is.

FIG. 29 is a diagram showing an operating state of operation when generating three temperatures when the difference between two condensation temperatures and one evaporation temperature is relatively large in the multi-temperature generation circuit by the vapor compression refrigeration cycle according to Embodiment 6 of the present invention. Is.

FIG. 30 is a diagram showing the operating state of operation when generating three temperatures when the difference between one condensation temperature and two evaporation temperatures is relatively small in the multi-temperature generation circuit using the vapor compression refrigeration cycle according to Embodiment 6 of the present invention. Is.

FIG. 31 is a diagram showing an operating state of operation when generating three temperatures when the difference between one condensation temperature and two evaporation temperatures is relatively large in the multi-temperature generation circuit by the vapor compression refrigeration cycle according to the sixth embodiment of the present invention. Is.

FIG. 32 is a configuration diagram of a refrigerant system of a multi-temperature generation circuit by a vapor compression refrigeration cycle according to Embodiment 7 of the present invention.

FIG. 33 is a diagram showing the operating state during two-temperature generation when the difference between the condensation temperature and the evaporation temperature is relatively small in the multi-temperature generation circuit by the vapor compression refrigeration cycle according to the seventh embodiment of the present invention.

[Fig. 34] Fig. 34 is a diagram showing the operation state during two-temperature generation when the difference between the condensation temperature and the evaporation temperature is relatively large in the multi-temperature generation circuit by the vapor compression refrigeration cycle according to the seventh embodiment of the present invention.

FIG. 35 is a diagram showing an operating state of operation at the time of generating three temperatures when the difference between two condensation temperatures and one evaporation temperature is relatively small in the multi-temperature generation circuit by the vapor compression refrigeration cycle according to the seventh embodiment of the present invention. Is.

FIG. 36 is a diagram showing an operating state of operation when generating three temperatures when the difference between two condensation temperatures and one evaporation temperature is relatively large in the multi-temperature generation circuit by the vapor compression refrigeration cycle according to Embodiment 7 of the present invention. Is.

FIG. 37 is a diagram showing an operating state of operation when generating three temperatures when the difference between one condensation temperature and two evaporation temperatures is relatively small in the multi-temperature generation circuit by the vapor compression refrigeration cycle according to Embodiment 7 of the present invention. Is.

FIG. 38 is a diagram showing the operating state when generating three temperatures when the difference between one condensation temperature and two evaporation temperatures is relatively large in the multi-temperature generation circuit by the vapor compression refrigeration cycle according to Embodiment 7 of the present invention. Is.

FIG. 39 is a configuration diagram of a refrigerant system of a multi-temperature generation circuit by a vapor compression refrigeration cycle according to Embodiment 8 of the present invention.

[Fig. 40] Fig. 40 is a diagram showing the operating state during two-temperature generation when the difference between the condensation temperature and the evaporation temperature is relatively small in the multi-temperature generation circuit by the vapor compression refrigeration cycle according to the eighth embodiment of the present invention.

[Fig. 41] Fig. 41 is a diagram showing the operating state when two temperatures are generated in the multi-temperature generation circuit by the vapor compression refrigeration cycle according to Embodiment 8 of the present invention when the difference between the condensation temperature and the evaporation temperature is relatively large.

FIG. 42 is a diagram showing the operating state of the multi-temperature generation circuit using the vapor compression refrigeration cycle according to the eighth embodiment of the present invention when three temperatures are generated when the difference between two condensation temperatures and one evaporation temperature is relatively small. Is.

FIG. 43 is a diagram showing an operating state of operation at the time of generating three temperatures in the case where the difference between two condensation temperatures and one evaporation temperature is relatively large in the multi-temperature generation circuit by the vapor compression refrigeration cycle according to Embodiment 8 of the present invention. Is.

FIG. 44 is a diagram showing the operating state of operation when generating three temperatures when the difference between one condensation temperature and two evaporation temperatures is relatively small in the multi-temperature generation circuit by the vapor compression refrigeration cycle according to Embodiment 8 of the present invention. Is.

FIG. 45 is a diagram showing the operating state when generating three temperatures when the difference between one condensation temperature and two evaporation temperatures is relatively large in the multi-temperature generation circuit by the vapor compression refrigeration cycle according to Embodiment 8 of the present invention. Is.

FIG. 46 is a configuration diagram of a refrigerant system of a multi-temperature generation circuit by a vapor compression refrigeration cycle of Embodiment 9 of the present invention.

[Fig. 47] Fig. 47 is an operation state diagram during two-temperature generation in which the difference between the condensation temperature and the evaporation temperature of the multi-temperature generation circuit in the vapor compression refrigeration cycle according to the ninth embodiment of the present invention is relatively small.

[Fig. 48] Fig. 48 is an operation state diagram during two-temperature generation in which the difference between the condensation temperature and the evaporation temperature of the multi-temperature generation circuit in the vapor compression refrigeration cycle according to the ninth embodiment of the present invention is relatively large.

[Fig. 49] Fig. 49 is an operation state diagram of the multi-temperature generation circuit using the vapor compression refrigeration cycle of the ninth embodiment of the present invention when generating three temperatures with a relatively small difference between two condensation temperatures and one evaporation temperature.

[Fig. 50] Fig. 50 is an operation state diagram of the multi-temperature generation circuit using the vapor compression refrigeration cycle according to the ninth embodiment of the present invention at the time of generating three temperatures in which the difference between two condensation temperatures and one evaporation temperature is relatively large.

[Fig. 51] Fig. 51 is an operation state diagram of the multi-temperature generation circuit using the vapor compression refrigeration cycle of the ninth embodiment of the present invention at the time of generating three temperatures in which the difference between one condensation temperature and two evaporation temperatures is relatively small.

[Fig. 52] Fig. 52 is an operation state diagram of the multi-temperature generation circuit in the vapor compression refrigeration cycle according to the ninth embodiment of the present invention when generating three temperatures with a relatively small difference between one condensation temperature and two evaporation temperatures.

[Fig. 53] Fig. 53 is an operation state diagram of the multi-temperature generation circuit in the vapor compression refrigeration cycle of the ninth embodiment of the present invention when three temperatures in which a difference between one condensation temperature and two evaporation temperatures is relatively large are generated.

FIG. 54 is a diagram showing the operating state of the multi-temperature generation circuit in the vapor compression refrigeration cycle of the ninth embodiment of the present invention at the time of generating three temperatures in which the difference between one condensation temperature and two evaporation temperatures is relatively large.

[Fig. 55] Fig. 55 is a configuration diagram of a refrigerant system of a multi-temperature generation circuit by a vapor compression refrigeration cycle of Embodiment 10 of the present invention.

[Fig. 56] Fig. 56 is an operation state diagram during two-temperature generation in which the difference between the condensation temperature and the evaporation temperature of the multi-temperature generation circuit in the vapor compression refrigeration cycle according to the tenth embodiment of the present invention is relatively small.

[Fig. 57] Fig. 57 is an operation state diagram during two-temperature generation in which the difference between the condensation temperature and the evaporation temperature of the multi-temperature generation circuit in the vapor compression refrigeration cycle according to the tenth embodiment of the present invention is relatively large.

[Fig. 58] Fig. 58 is an operation state diagram of the multi-temperature generation circuit using the vapor compression refrigeration cycle of the tenth embodiment of the present invention at the time of generating two temperatures in which the difference between the condensation temperature and the evaporation temperature is relatively large.

[Fig. 59] Fig. 59 is an operation state diagram of the multi-temperature generation circuit using the vapor compression refrigeration cycle of the tenth embodiment of the present invention when three temperatures at which the difference between two condensation temperatures and one evaporation temperature is relatively small are generated.

[Fig. 60] Fig. 60 is an operation state diagram of the multi-temperature generation circuit using the vapor compression refrigeration cycle of the tenth embodiment of the present invention at the time of generating three temperatures in which the difference between two condensation temperatures and one evaporation temperature is relatively small.

[Fig. 61] Fig. 61 is an operation state diagram of the multi-temperature generation circuit using the vapor compression refrigeration cycle of the tenth embodiment of the present invention at the time of generating three temperatures in which the difference between two condensation temperatures and one evaporation temperature is relatively large.

[Fig. 62] Fig. 62 is a diagram showing the operating state of the multi-temperature generation circuit in the vapor compression refrigeration cycle of the tenth embodiment of the present invention at the time of generating three temperatures in which the difference between the two condensation temperatures and the one evaporation temperature is relatively large.

[Fig. 63] Fig. 63 is a diagram showing the operating state of the multi-temperature generation circuit using the vapor compression refrigeration cycle of the tenth embodiment of the present invention when generating three temperatures in which the difference between one condensation temperature and two evaporation temperatures is relatively small.

[Fig. 64] Fig. 64 is a diagram showing the operating state of the multi-temperature generation circuit in the vapor compression refrigeration cycle of the tenth embodiment of the present invention at the time of generating three temperatures in which the difference between one condensation temperature and two evaporation temperatures is relatively small.

[Fig. 65] Fig. 65 is an operation state diagram of the multi-temperature generation circuit using the vapor compression refrigeration cycle of the tenth embodiment of the present invention at the time of generating three temperatures in which the difference between one condensation temperature and two evaporation temperatures is relatively large.

[Fig. 66] Fig. 66 is an operation state diagram of the multi-temperature generation circuit in the vapor compression refrigeration cycle of the tenth embodiment of the present invention at the time of generating three temperatures in which the difference between one condensation temperature and two evaporation temperatures is relatively large.

[Fig. 67] Fig. 67 is a configuration diagram of a refrigerant system of a multi-temperature generation circuit by a vapor compression refrigeration cycle of Embodiment 11 of the present invention.

[Fig. 68] Fig. 68 is an operation state diagram of the multi-temperature generation circuit using the vapor compression refrigeration cycle of the eleventh embodiment of the present invention at the time of generating two temperatures in which the difference between the condensation temperature and the evaporation temperature is relatively small.

[Fig. 69] Fig. 69 is an operation state diagram during two-temperature generation in which the difference between the condensation temperature and the evaporation temperature of the multi-temperature generation circuit in the vapor compression refrigeration cycle according to the eleventh embodiment of the present invention is relatively large.

[Fig. 70] Fig. 70 is a diagram showing the operation state during two-temperature generation in which the difference between the condensation temperature and the evaporation temperature of the multi-temperature generation circuit in the vapor compression refrigeration cycle according to the eleventh embodiment of the present invention is relatively large.

FIG. 71 is an operation state diagram of the multi-temperature generation circuit using the vapor compression refrigeration cycle of the eleventh embodiment of the present invention at the time of generating three temperatures in which the difference between the two condensation temperatures and the one evaporation temperature is relatively small.

[Fig. 72] Fig. 72 is a diagram showing the operating state of the multi-temperature generation circuit using the vapor compression refrigeration cycle of the eleventh embodiment of the present invention when generating three temperatures with a relatively small difference between the two condensation temperatures and one evaporation temperature.

[Fig. 73] Fig. 73 is an operation state diagram of the multi-temperature generation circuit using the vapor compression refrigeration cycle according to the eleventh embodiment of the present invention when three temperatures at which the difference between two condensation temperatures and one evaporation temperature is relatively large are generated.

[Fig. 74] Fig. 74 is an operation state diagram of the multi-temperature generation circuit using the vapor compression refrigeration cycle according to the eleventh embodiment of the present invention when three temperatures at which the difference between two condensation temperatures and one evaporation temperature is relatively large are generated.

[Fig. 75] Fig. 75 is an operation state diagram of the multi-temperature generation circuit according to the eleventh embodiment of the present invention at the time of generating three temperatures in which the difference between one condensation temperature and two evaporation temperatures is relatively small.

[Fig. 76] Fig. 76 is an operation state diagram of the multi-temperature generation circuit according to the eleventh embodiment of the present invention when generating three temperatures with a relatively small difference between one condensation temperature and two evaporation temperatures.

[Fig. 77] Fig. 77 is an operational state diagram of the multi-temperature generation circuit using the vapor compression refrigeration cycle of the eleventh embodiment of the present invention when generating three temperatures with a relatively large difference between one condensation temperature and two evaporation temperatures.

[Fig. 78] Fig. 78 is a diagram showing the operating state of the multi-temperature generation circuit according to the eleventh embodiment of the present invention when generating three temperatures in which the difference between one condensation temperature and two evaporation temperatures is relatively large.

[Fig. 79] Fig. 79 is a configuration diagram of a refrigerant system of a multi-temperature generation circuit by a vapor compression refrigeration cycle of Embodiment 12 of the present invention.

[Fig. 80] Fig. 80 is an operation state diagram during two-temperature generation in which the difference between the condensation temperature and the evaporation temperature of the multi-temperature generation circuit in the vapor compression refrigeration cycle according to the twelfth embodiment of the present invention is relatively small.

FIG. 81 is an operation state diagram of the multi-temperature generation circuit in the vapor compression refrigeration cycle of the twelfth embodiment of the present invention at the time of generating two temperatures in which the difference between the condensation temperature and the evaporation temperature is relatively large.

[Fig. 82] Fig. 82 is a diagram showing the operating state of the multi-temperature generation circuit according to the twelfth embodiment of the present invention at the time of generating three temperatures in which the difference between two condensation temperatures and one evaporation temperature is relatively small.

[Fig. 83] Fig. 83 is an operation state diagram of the twelfth embodiment of the present invention at the time of generating three temperatures in which the difference between two condensation temperatures and one evaporation temperature in the multi-temperature generation circuit by the vapor compression refrigeration cycle is relatively large.

[Fig. 84] Fig. 84 is an operation state diagram of the multi-temperature generation circuit using the vapor compression refrigeration cycle of the twelfth embodiment of the present invention when generating three temperatures with a relatively small difference between one condensation temperature and two evaporation temperatures.

[Fig. 85] Fig. 85 is an operation state diagram of the multi-temperature generation circuit using the vapor compression refrigeration cycle of the twelfth embodiment of the present invention when generating three temperatures in which the difference between one condensation temperature and two evaporation temperatures is relatively large.

[Fig. 86] Fig. 86 is a configuration diagram of a refrigerant system of a conventional vapor compression cycle.

[Fig. 87] Fig. 87 is a diagram showing the operating state of the conventional vapor compression cycle.

[Explanation of symbols]

 1 1st compressor 2 2nd compressor 3 3rd compressor 4a-d opening / closing valve 5 1st gas pipe 6 2nd gas pipe 7 3rd gas pipe 8 4th gas pipe 11 1st accumulator 12 2nd accumulator 13th 3 Discharge pipe of the compressor 14 Discharge pipe of the 2nd compressor 15 Discharge pipe of the 1st compressor 16 Suction pipe of the 3rd compressor 17 Suction pipe of the 2nd compressor 18 Suction pipe of the 1st compressor 20a ~ d Opening / closing Valve 21 1st opening / closing valve 22 2nd opening / closing valve 23 3rd opening / closing valve 24 4th opening / closing valve 25 5th opening / closing valve 26a-d opening / closing valve 27a-d opening / closing valve 28a-d opening / closing valve 29a-d opening / closing valve 30a 7th opening / closing Valve 30b Eighth on-off valve 30d Sixth on-off valve 31a-d Expansion valve 32 Capillary tube 33 Refrigerant flow controller 41 First check valve 42 Second check valve 51a-c Heat exchanger 52 First check valve 53th 1 on-off valve 54 second Stop valve 55 Third check valve 56 Accumulator 57 Heat exchanger for hot water supply 58 Heat exchanger for reheating 59 Indoor heat exchanger 60 Outdoor heat exchanger 61 High pressure gas pipe 62 Second high pressure gas pipe 63 Low pressure gas pipe 64 Liquid Pipe 65 High-pressure gas communication pipe 66 Compressor communication pipe 67 Second bypass pipe 68 First bypass pipe 69 Liquid receiver 71 Heat exchange section 72 First discharge pipe 73 Third switching four-way valve 74 Second discharge pipe 76 First suction pipe 78 Second suction pipe 80 First bypass pipe 82 Second bypass pipe 83 Discharge side connection pipe 86 Suction side connection pipe 89 Third bypass pipe 91 Fifth bypass pipe 93 Fourth bypass pipe Pipe 121 First on-off valve 123 Second on-off valve 125 Third on-off valve 127 Fourth on-off valve 129 Fifth on-off valve 131 Sixth on-off valve 134 Seventh on-off valve 135 Eighth Open / close valve 137 9th open / close valve 138 10th open / close valve 140 11th open / close valve 142 12th open / close valve 144 13th open / close valve 150 4 way valve 180 2nd discharge pipe 181 1st open / close valve 182 1st Discharge pipe 183 First four-way valve 184 Second suction pipe 185 Second opening / closing valve 186 First connecting pipe 187 Second four-way valve 188 Second connecting pipe 189 Third opening / closing valve 190 Third connection Pipe 191 4th on-off valve 192 5th on-off valve 193 4th connecting pipe 194 1st suction pipe 195 5th connecting pipe 271 1st switching four-way valve 272 2nd switching four-way valve 273 3rd switching four-way valve

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tetsuji Shichika 3-18-1, Ogashi, Shizuoka City Mitsubishi Electric Corporation Shizuoka Manufacturing Co., Ltd. (72) Inventor Tetsuji Okada 3-18-1, Oka Shizuoka Mitsubishi Electric Corporation Company Shizuoka Factory (72) Inventor Yuyama ▲ Hiroshi ▼ 3-18-1, Oga, Shizuoka City Mitsubishi Electric Co., Ltd. Shizuoka Factory (72) Inventor Fumio Matsuoka 2-14-40 Ofuna, Kamakura City Mitsubishi Electric Company Life System Research Laboratory (72) Inventor Seiji Inoue 2-14-40 Ofuna, Kamakura City Mitsubishi Electric Corporation Life Systems Research Laboratory (72) Inventor Yoshihiro Sumida 8-1-1 Tsukaguchihonmachi, Amagasaki Mitsubishi Electric Corporation In-house (72) Inventor Naoki Tanaka 8-1-1 Tsukaguchihonmachi, Amagasaki City Mitsubishi Electric Corporation Central Research Laboratory

Claims (17)

[Claims] 1. A plurality of compressors that can be connected in series or in parallel through a plurality of on-off valves or check valves, and one of the discharge side and each suction side of the compressors. Via a switching valve or a check valve, or a plurality of gas pipes directly connected to each of the discharge side or the suction side of the compressor on the other side, via the switching valve or the check valve, Alternatively, at least one other gas pipe that is directly connected to the plurality of gas pipes and the other gas pipes has one end connected to each other via an opening / closing valve, and the other end is connected to a refrigerant via a pressure reducing means. A multi-temperature generation circuit using a vapor compression refrigeration cycle equipped with a plurality of heat exchangers, each of which is connected to a common refrigerant pipe. 2. A first compressor, a second compressor, and a plurality of heat exchangers, one end of which is either a discharge side or a suction side of the first compressor, and the other end of which is opened and closed. High pressure gas pipe connected to the plurality of heat exchangers via a compressor, one end of which is either the discharge side or the suction side of the second compressor via the first switch, and the other end is Is connected to the plurality of heat exchangers via a switch, and is branched midway to be connected to either the suction side or the discharge side of the first compressor via the second switch. High-pressure gas pipe, one end of which is connected to either the suction side or the discharge side of the second compressor, and the other side of which is connected to the suction side or the discharge side of the first compressor via a third switch. Then
Through the low pressure gas pipe whose other end is connected to the plurality of heat exchangers via a switch, the liquid pipe connected to the plurality of heat exchangers via a refrigerant flow controller, and the fourth switch. Vapor compression constituted by connecting a discharge side of the second compressor and a suction side of the first compressor and providing a compressor communication pipe for feeding the discharge gas of the second compressor to the first compressor Multi-temperature generation circuit by the freezing cycle. 3. A high pressure gas communication for connecting the discharge side of the second compressor and the first high pressure gas pipe via a fifth switch to feed the discharge gas of the second compressor to the first high pressure gas pipe. The multi-temperature generation circuit according to claim 2, wherein a pipe is provided. 4. The discharge pipe of the second compressor branches into a common pipe for the second high-pressure gas pipe, the high-pressure gas communication pipe, and the compressor communication pipe, and further branches into the high-pressure gas communication pipe and the compressor communication pipe pipe. The high-pressure gas communication pipe is connected to the first high-pressure gas pipe, and the compressor communication pipe is connected to the low-pressure gas pipe between the check valve and the on-off valve forming the third switch to connect to the first compressor. The multi-temperature generation circuit according to claim 3, which is in communication with the vapor compression refrigeration cycle. 5. The first accumulator is provided in the low pressure gas pipe on the suction side of the first compressor and the second compressor, and the second accumulator is provided in the second high pressure gas pipe on the suction side of the first compressor. A multi-temperature generation circuit using the vapor compression refrigeration cycle according to any one of items 2 to 4. 6. A liquid pipe and a first accumulator are connected,
By-pass piping having a sixth switch and a flow controller in the pipeline,
6. A multi-temperature generation by a vapor compression refrigeration cycle according to claim 5, further comprising a heat exchanging section for exchanging heat between the bypass pipe between the flow rate controller and the first accumulator and the suction pipe of the first compressor. circuit. 7. The multi-temperature generation circuit according to any one of claims 2 to 6, wherein the first compressor or the second compressor is a variable capacity compressor. 8. A vapor compression refrigeration cycle capable of simultaneously obtaining n saturation temperatures, comprising n-1 compressors, each compressor being connected in series via a plurality of on-off valves or check valves. A group of n gas pipes that are connected in parallel and that have one end connected to each of the discharge or suction sides of the compressor and the other end connected to a plurality of heat exchangers through open / close valves and have an arbitrary saturation temperature And a single liquid pipe connected to the plurality of heat exchangers via a refrigerant flow control valve. 9. A first compressor, a second compressor and a plurality of heat exchangers are provided, wherein one end of the first compressor is provided with a first check valve.
Either the discharge side or the suction side of the compressor, the other end is a first gas pipe connected to the plurality of heat exchangers via an on-off valve, and the one end is the discharge side of the second compressor or The second gas pipe, which has the other end connected to the plurality of heat exchangers via the on-off valve on one side of the suction side, the other end on the other side of the suction side or the discharge side of the accumulator, and the other end The third part is connected to multiple heat exchangers via open / close valves
A gas pipe and a liquid pipe connected to a plurality of heat exchangers via a refrigerant flow rate controller are provided, and the discharge side of the accumulator and the suction sides of the first and second compressors are respectively provided with a second pipe and a second pipe. 3 are individually connected via a check valve, and the pipe on the first check valve outlet side of the first gas pipe and the second gas pipe are communicated with each other via the first on-off valve. A multi-temperature generation circuit using a vapor compression refrigeration cycle. 10. A plurality of heat exchangers including a first compressor, a second compressor and a hot water supply heat exchanger, a bath reheating heat exchanger, an indoor heat exchanger, and an outdoor heat exchanger, one end of which is provided. A hot water supply heat exchanger through the first check valve to either the discharge side or the suction side of the first compressor, and the other end through an open / close valve;
First connected to each of the additional heat exchanger and the outdoor heat exchanger
A gas pipe, one end of which is connected to either the discharge side or the suction side of the second compressor, and the other end of which is connected to an indoor heat exchanger or an outdoor heat exchanger via an on-off valve, A third gas pipe whose one end is connected to either the suction side or the discharge side of the accumulator and the other end is connected to each of the plurality of heat exchangers through an on-off valve, and the plurality of heat exchangers are connected. A liquid pipe connected to each of them via a refrigerant flow rate controller is provided, and the discharge side of the accumulator and the suction sides of the first and second compressors are respectively connected via second and third check valves. According to a vapor compression refrigeration cycle, which is characterized in that the first gas pipe is connected to the first check valve outlet side of the first gas pipe and the second gas pipe is communicated with the second gas pipe via a first opening / closing valve. Multi-temperature generation circuit. 11. A first compressor, a second compressor, a plurality of heat exchangers, one end of which is on the discharge side of the first compressor, and the other end of which is provided with an opening / closing valve. A high-pressure gas pipe connected to the exchanger, one end connected to the discharge side of the second compressor via the first opening / closing valve, and the other end connected to the plurality of heat exchangers via the opening / closing valve. A medium pressure gas pipe branched from between the first on-off valve and the on-off valve and connected to the suction side of the first compressor via a fifth on-off valve and a second check valve, and one end of the second on-off valve
The first check valve and the second check valve are connected to the suction side of the compressor.
A low-pressure gas pipe connected to the suction side of the first compressor through the on-off valve in this order, and the other end connected to the heat exchangers through the on-off valve, and the heat exchangers A liquid pipe connected via a refrigerant flow controller, a high pressure gas communication pipe connecting the discharge side of the first compressor and the discharge side of the second compressor via a third opening / closing valve, and the second compression Compressor communication pipe connecting the discharge side of the machine with the first check valve and the second open / close valve via a fourth open / close valve, and the liquid pipe from the intermediate pressure gas pipe through a seventh open / close valve To the suction side of the first compressor from the liquid pipe via the eighth opening / closing valve.
A multi-temperature generation circuit by a vapor compression refrigeration cycle including a bypass path. 12. A first compressor, a second compressor, a plurality of heat exchangers, one end of which is on the discharge side of the first compressor, and the other end of which is provided with an opening / closing valve. A high-pressure gas pipe connected to the exchanger, one end connected to the discharge side of the second compressor via the first opening / closing valve, and the other end connected to the plurality of heat exchangers via the opening / closing valve. A medium pressure gas pipe branched from between the first on-off valve and the on-off valve and connected to the suction side of the first compressor via a fifth on-off valve and a second check valve, and one end of the second on-off valve
The first check valve and the second check valve are connected to the suction side of the compressor.
A low-pressure gas pipe connected to the suction side of the first compressor through the on-off valve in this order, and the other end connected to the heat exchangers through the on-off valve, and the heat exchangers A liquid pipe connected via a refrigerant flow controller, a high pressure gas communication pipe connecting the discharge side of the first compressor and the discharge side of the second compressor via a third opening / closing valve, and the second compression A compressor communication pipe connecting the discharge side of the machine with the first check valve and the second open / close valve via a fourth open / close valve, and the liquid pipe from the intermediate pressure gas pipe via a refrigerant flow controller. A multi-temperature generation circuit by a vapor compression refrigeration cycle, which includes a first bypass passage leading to the liquid pipe and a second bypass passage extending from the liquid pipe to the suction side of the first compressor via an eighth opening / closing valve. 13. A first compressor, a second compressor, a plurality of heat exchangers, one end of which is on the discharge side of the first compressor, and the other end of which is provided with an opening / closing valve. A high-pressure gas pipe connected to the exchanger, one end connected to the discharge side of the second compressor via the first opening / closing valve, and the other end connected to the plurality of heat exchangers via the opening / closing valve. A medium pressure gas pipe branched from between the first on-off valve and the on-off valve and connected to the suction side of the first compressor via a fifth on-off valve and a second check valve, and one end of the second on-off valve
The first check valve and the second check valve are connected to the suction side of the compressor.
A low-pressure gas pipe connected to the suction side of the first compressor through the on-off valve in this order, and the other end connected to the heat exchangers through the on-off valve, and the heat exchangers A liquid receiver connected via a refrigerant flow controller, a high pressure gas communication pipe connecting the discharge side of the first compressor and the discharge side of the second compressor via a third on-off valve, and the second The compressor communication pipe that connects the discharge side of the compressor to the first check valve and the second open / close valve via a fourth open / close valve;
Vapor compression type having a first bypass passage leading to the liquid receiver via an on-off valve and a second bypass passage leading from the liquid receiver to the suction side of the first compressor via an eighth on-off valve Multi-temperature generation circuit by refrigeration cycle. 14. A discharge side of the first compressor via a first compressor, a second compressor, a plurality of heat exchangers, and a first discharge pipe having a first opening / closing valve at one end. A high pressure gas pipe having the other end connected to the plurality of heat exchangers via an on-off valve,
A medium pressure gas pipe having one end connected to the discharge side of the second compressor via a second discharge pipe having a second on-off valve, and the other end connected to the plurality of heat exchangers via an on-off valve. A low pressure gas pipe having one end connected to the suction side of the second compressor via a second suction pipe having a fourth on-off valve and the other end connected to the plurality of heat exchangers via the on-off valve. A liquid pipe connected to the plurality of heat exchangers via a refrigerant flow controller, the medium pressure gas pipe and a suction side of the first compressor connected via a third opening / closing valve, Suction pipe, a discharge-side connecting pipe that connects the first discharge pipe and the second discharge pipe via a seventh opening / closing valve and an eighth opening / closing valve, the first suction pipe, and the first suction pipe. The suction side connecting pipe connecting the second suction pipe through the ninth opening and closing valve and the tenth opening and closing valve, the intermediate pressure gas pipe and the second suction pipe through the fifth opening and closing valve. Between the continuing first bypass pipe, the second bypass pipe connecting the low pressure pipe and the first suction pipe via the sixth opening / closing valve, the seventh opening / closing valve, and the eighth opening / closing valve. And between the ninth on-off valve and the tenth on-off valve above
Third bypass pipe connected via the on-off valve, a fourth bypass pipe connecting the second discharge pipe and the high-pressure gas pipe via the thirteenth open-close valve, and the first discharge pipe A fifth connecting the pipe and the medium pressure gas pipe through a twelfth on-off valve
A multi-temperature generation circuit using a vapor compression refrigeration cycle, which includes a bypass pipe of. 15. The first compressor via a first compressor, a second compressor, a plurality of heat exchangers, a four-way valve, and a first discharge pipe having a first opening / closing valve at one end. On the discharge side of the machine, the other end is connected to the plurality of heat exchangers via an on-off valve, and the second compression pipe is connected via a second discharge pipe having a second on-off valve at one end. On the discharge side of the machine, the other end is connected to the plurality of heat exchangers via an on-off valve, a medium pressure gas pipe branched from the middle and connected to the four-way valve, and one end to the four-way valve, The other is a low-pressure gas pipe connected to the plurality of heat exchangers via an on-off valve, a liquid pipe connected to the plurality of heat exchangers via a refrigerant flow controller, the four-way valve, and the first A first suction pipe connecting the suction side of the compressor via a third opening / closing valve, and a fourth opening / closing valve connecting the four-way valve and the suction side of the second compressor. A second suction pipe connected via
A discharge side connecting pipe that connects the first discharge pipe and the second discharge pipe via a seventh opening / closing valve and an eighth opening / closing valve, the first suction pipe, and the second suction pipe. Between the suction side connecting pipe connected through the ninth opening / closing valve and the tenth opening / closing valve, between the seventh opening / closing valve and the eighth opening / closing valve, and between the ninth opening / closing valve and the tenth opening / closing valve. A third bypass pipe connecting the two via an eleventh on-off valve, a fourth bypass pipe connecting the second discharge pipe and the high-pressure gas pipe via a thirteenth open-close valve, and A multi-temperature generation circuit according to a vapor compression refrigeration cycle, comprising: a first discharge pipe and a fifth bypass pipe connecting the medium pressure gas pipe via a twelfth on-off valve. 16. A first compressor, a second compressor, a plurality of heat exchangers, a first four-way valve, a second four-way valve, and one end of which is connected to the first four-way valve. Through the first discharge pipe to the discharge side of the first compressor, the other end through a high pressure gas pipe connected to the plurality of heat exchangers through the open / close valve, and the other end through the open / close valve. A medium pressure gas pipe connected to the plurality of heat exchangers, a second suction pipe having one end connected to the suction side of the second compressor via a second opening / closing valve, and the other end having an opening / closing valve. A low pressure gas pipe connected to the plurality of heat exchangers via a liquid pipe, a liquid pipe connected to the plurality of heat exchangers via a refrigerant flow controller, the low pressure gas pipe and the first compressor. A first suction pipe connected via the second four-way valve, a first connection connecting the discharge side of the second compressor and the first on-off valve, and the first four-way valve. A pipe, a second connecting pipe connecting the second four-way valve between the suction side of the second compressor and the second on-off valve, the first four-way valve and the second connecting pipe. A third connecting pipe connecting a four-way valve via a third opening / closing valve and a branch from both sides of the third opening / closing valve, and the medium pressure via the fourth opening / closing valve and the fifth opening / closing valve, respectively. A multi-temperature generation circuit by a vapor compression refrigeration cycle including a fourth connection pipe and a fifth connection pipe connected to one end of a gas pipe. 17. A first compressor, a second compressor, a hot water heat exchanger and a plurality of heat exchangers, a first four-way valve, a second four-way valve, and a third four-way valve. And one end connected to the discharge side of the first compressor and the other end connected to the plurality of heat exchangers via the heat exchanger for hot water supply, the first four-way valve, and the third four-way valve. A gas pipe, one end of which is connected to the discharge side of the second compressor through the first opening / closing valve, and the other end of which is a second four-way valve, a third
A medium pressure gas pipe connected to the plurality of heat exchangers via the four-way valve, and branched in the middle to connect to the suction side of the first compressor via the fifth opening / closing valve; The first check valve and the second opening / closing valve are connected to the suction side of the first compressor via the first check valve and the second opening / closing valve in this order,
A low-pressure gas pipe having the other end connected to the plurality of heat exchangers via a first four-way valve and a second four-way valve, the hot water supply heat exchanger and the plurality of heat exchangers, and a refrigerant flow rate controller. And a high pressure gas communication pipe connecting the discharge side of the first compressor and the discharge side of the second compressor via a third opening / closing valve, and the discharge side of the second compressor. And a compressor communication pipe that connects the first check valve and the second opening / closing valve via a fourth opening / closing valve, and a multi-temperature generation circuit by a vapor compression refrigeration cycle.