Cooling system and vending machine

Abstract

To provide a cooling system and a vending machine capable of improving energy saving performance of the cooling system by reducing power consumption of a compressor while maintaining cooling performance by a refrigerating cycle.SOLUTION: The cooling system 100 includes a refrigeration cycle 1, an ejector cycle 2, and a heat exchanger 3, and the refrigeration cycle 1 includes a condensing portion 11 including the heat exchanger 3 that condenses a first refrigerant by performing heat exchange between the first refrigerant and a second refrigerant, and the ejector cycle 2 includes the heat exchanger 3 that evaporates the second refrigerant by performing heat exchange between the second refrigerant and the first refrigerant, a vapor generator 24 that evaporates the second refrigerant by an external heat source, and an ejector 25 that introduces the second refrigerant evaporated by the vapor generator 24 as a drive flow to introduce the second refrigerant flowing out of the heat exchanger 3 as a suction flow and discharges the second refrigerant in which the drive flow and the suction flow are mixed to send the second refrigerant to a second condenser 20.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a refrigeration system and a vending machine. [Background technology]

[0002] BACKGROUND ART Conventionally, vending machines have been known (see, for example, Patent Document 1).

[0003] The above-mentioned Patent Document 1 discloses a vending machine equipped with a cooling device (refrigeration cycle). The cooling device cools products stored in a product storage compartment. The cooling device includes a compressor that compresses a refrigerant, a condenser (first condenser) that condenses the compressed refrigerant, an expansion mechanism (first expansion section) that expands the condensed refrigerant, and an evaporator that evaporates the refrigerant to cool the air in the product storage compartment. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-118911 Summary of the Invention [Problem to be solved by the invention]

[0005] In a cooling device (refrigeration cycle) such as that described in Patent Document 1, the compressor compresses a low-temperature, low-pressure gas-phase refrigerant to produce a high-temperature, high-pressure gas-phase refrigerant, so a certain amount of power is required to drive the compressor. As a result, the power consumption of the cooling device increases by the amount required to drive the compressor. Therefore, it is desirable to improve the energy-saving performance of the cooling system by reducing the power consumption of the compressor while maintaining the cooling performance of the refrigeration cycle.

[0006] The present invention has been made to solve the above-mentioned problems, and one object of the present invention is to provide a cooling system and a vending machine that can improve the energy-saving performance of the cooling system by reducing the power consumption of the compressor while maintaining the cooling performance of the refrigeration cycle. [Means for solving the problem]

[0007] In order to achieve the above object, a cooling system according to a first aspect of the present invention includes a refrigeration cycle, an ejector cycle, and a heat exchanger provided across the refrigeration cycle and the ejector cycle, wherein the refrigeration cycle includes a condensing section including a compressor that compresses a first refrigerant, a first condenser connected in series downstream of the compressor and that condenses the first refrigerant, and a heat exchanger that condenses the first refrigerant by exchanging heat between the first refrigerant and a second refrigerant circulating through the ejector cycle, a first expansion valve that expands the first refrigerant flowing out of the condensing section, and an evaporator that cools an object to be cooled by evaporating the first refrigerant expanded by the first expansion valve, and the ejector cycle includes a second condenser that condenses the second refrigerant, and an evaporator provided in a flow path downstream of the second condenser. a first branch section connected to the second condenser; a second expansion valve that expands a portion of the second refrigerant that flows out of the second condenser and through the first branch section; a heat exchanger that evaporates the second refrigerant by exchanging heat between the second refrigerant expanded by the second expansion valve and the first refrigerant; a liquid feed pump that feeds all but a portion of the second refrigerant that flows out of the second condenser and through the first branch section; a vapor generator that evaporates the second refrigerant fed from the liquid feed pump using an external heat source; and an ejector that introduces the second refrigerant evaporated in the vapor generator from an inlet as a driving flow, introduces the second refrigerant that flows out of the heat exchanger from a suction port as a suction flow, and discharges the second refrigerant, a mixture of the driving flow and the suction flow, from a discharge port, thereby sending the second refrigerant to the second condenser.

[0008] A cooling system according to a first aspect of the present invention includes a heat exchanger disposed between a refrigeration cycle and an ejector cycle. The ejector cycle includes a vapor generator that evaporates a second refrigerant using an external heat source, and an ejector that introduces the second refrigerant evaporated by the vapor generator through an inlet as a driving flow, introduces the second refrigerant flowing out of the heat exchanger through a suction port, and discharges a mixture of the driving flow and the suction flow through a discharge port, thereby sending the second refrigerant to a second condenser. This allows the ejector cycle to lower the temperature of the second refrigerant in the heat exchanger below the ambient temperature, and heat exchange occurs between the second refrigerant and the first refrigerant in the refrigeration cycle, evaporating the second refrigerant and condensing the first refrigerant. This lowers the condensing temperature of the first condenser compared to a system without an ejector cycle, thereby reducing the power consumption of the compressor. As a result, the energy-saving performance of the cooling system can be improved by reducing the power consumption of the compressor while maintaining the cooling performance of the refrigeration cycle.

[0009] In the cooling system according to the first aspect, the heat exchanger in the condensing section is preferably arranged downstream of the first condenser and upstream of the first expansion valve. With this configuration, the heat exchanger that exchanges heat between the first refrigerant and the second refrigerant that is lower in temperature than the outside air is arranged downstream of the first condenser that exchanges heat between the first refrigerant and the outside air, so that the first refrigerant can be condensed efficiently in the condensing section.

[0010] In the cooling system according to the first aspect, preferably, the ejector cycle further includes a third condenser that heats the heating target by condensing the second refrigerant flowing out of the steam generator, a third expansion valve that is provided downstream of the third condenser and expands the second refrigerant, and a first switching unit that is provided between the steam generator and an inlet of the ejector and switches between a cooling operation in which all of the second refrigerant flowing out of the steam generator flows into the ejector and a cooling / heating operation in which some of the second refrigerant flowing out of the steam generator flows into the ejector and all but the part of the second refrigerant flowing out of the steam generator flows into the third condenser, and in the cooling / heating operation, all but the part of the second refrigerant flowing out of the first switching unit flows through the third condenser without flowing through the ejector and the heat exchanger, and flows into a flow path between the discharge port of the ejector and the second condenser via the third expansion valve. With this configuration, the heating target can be heated by condensing second refrigerant vapor generated by an external heat source in the third condenser, rather than using a heat utilization method in which heat obtained when cooling the refrigerator using a refrigeration cycle is transferred to the heating chamber to heat the heating target inside the heating chamber. This allows the heating target to be heated efficiently. Furthermore, the second refrigerant flowing out of the third condenser can be passed through the third expansion valve into the flow path between the ejector outlet and the second condenser, thereby equalizing the pressure of the second refrigerant discharged from the ejector outlet and the pressure of the second refrigerant flowing through the third expansion valve into the flow path between the ejector outlet and the second condenser. This reduces stress in the refrigerant piping due to a pressure difference between the pressure of the second refrigerant discharged from the ejector outlet and the pressure of the second refrigerant flowing through the third expansion valve into the flow path between the ejector outlet and the second condenser.

[0011] In the cooling system according to the first aspect, the second refrigerant is preferably a low-pressure refrigerant having a higher standard boiling point (boiling point at 1 atmospheric pressure) than the first refrigerant. A low-pressure refrigerant refers to a refrigerant having a relatively high standard boiling point (boiling point at 1 atmospheric pressure) and a relatively low differential pressure during operation. The power of the liquid pump in the ejector cycle is based on a pressure increase amount, which is the difference between the drive pressure and discharge pressure of the ejector. Since the refrigeration cycle and the ejector cycle have different refrigerant flow paths, different types of refrigerants can be used for the first refrigeration cycle and the second refrigerant in the ejector cycle. By using a low-pressure refrigerant having a higher standard boiling point than the first refrigerant and a low differential pressure during operation as the second refrigerant, the amount of pressure increase required by the liquid pump in the ejector cycle can be reduced. This increases the COP (Coefficient of Performance), which represents the operating efficiency of the ejector cycle, thereby improving the energy-saving performance of the entire cooling system. The COP, which indicates the operating efficiency of the ejector cycle, means the value obtained by dividing the cooling capacity by the power consumption of the liquid pump required to generate cold.

[0012] In the cooling system according to the first aspect, preferably, the ejector cycle further includes a third condenser that heats the heating target by condensing the second refrigerant flowing out of the steam generator, and a second switching unit that is provided between the steam generator and an inlet of the ejector and switches between a cooling operation in which all of the second refrigerant flowing out of the steam generator flows into the inlet of the ejector and a heating operation in which all of the second refrigerant flowing out of the steam generator flows into the third condenser without flowing into the inlet of the ejector, and the cooling system further includes a control unit that controls the switching between the cooling operation and the heating operation using the second switching unit, and in the heating operation switched from the cooling operation by the second switching unit, the control unit controls the second refrigerant flowing out of the second switching unit to flow through the third condenser without flowing through the ejector and the heat exchanger, and controls the second refrigerant flowing out of the third condenser to flow into a flow path between the second condenser and the first branching unit. With this configuration, the control unit switches between cooling operation and heating operation using the second switching unit, and the second refrigerant flowing out of the third condenser flows into the flow path between the second condenser and the first branch unit, eliminating the need to expand the second refrigerant using the third expansion valve and then pressurize it with a liquid feed pump, as in cooling and heating operation in which cooling operation and heating operation are performed in parallel.This reduces energy loss and further improves the energy-saving performance of the cooling system.

[0013] In this case, preferably, the device further includes a cooling object temperature detection unit that detects the temperature of the cooling object and a heating object temperature detection unit that detects the temperature of the heating object, and the control unit controls the second switching unit to switch between the cooling operation and the heating operation based on the temperature of the cooling object detected by the cooling object temperature detection unit and the temperature of the heating object detected by the heating object temperature detection unit. With this configuration, the control unit can easily switch between the cooling operation and the heating operation by the second switching unit based on the temperature of the cooling object detected by the cooling object temperature detection unit and the temperature of the heating object detected by the heating object temperature detection unit.

[0014] In a configuration in which the control unit controls switching between cooling operation and heating operation using the second switching unit based on the temperatures detected by the cooling object temperature detection unit and the heating object temperature detection unit, preferably, the ejector cycle further includes: a storage unit located downstream of the second condenser and upstream of the first branching unit, for storing the second refrigerant condensed by the second condenser; a second branching unit located in the flow path between the liquid feed pump and the steam generator; a bypass flow path branching from the second branching unit and joining a joining unit located in the flow path between the discharge port of the ejector and the second condenser; and a third switching unit located in the second branching unit, for switching between the flow path leading to the steam generator and the bypass flow path, and the control unit controls switching from heating operation to cooling operation using the second switching unit, and switching from the flow path leading to the steam generator to the bypass flow path using the third switching unit, thereby circulating the second refrigerant between the second condenser, the storage unit, and the liquid feed pump via the bypass flow path. With this configuration, when switching from heating operation to cooling operation by the second switching unit, the temperature of the second refrigerant can be quickly lowered by circulating the second refrigerant between the second condenser, the storage unit, and the liquid feed pump via the bypass flow path. Therefore, by introducing high-pressure second refrigerant from the inlet, the ejector can quickly be put into a state where low-pressure second refrigerant can be drawn in from the suction port and medium-pressure second refrigerant can be discharged from the discharge port, thereby quickly starting cooling operation.

[0015] In this case, preferably, the system further includes a second refrigerant temperature detector that detects the temperature of any one of the second refrigerant flowing out of the second condenser, the second refrigerant stored in the reservoir, and the second refrigerant flowing into the liquid feed pump, and the control unit, after controlling the third switching unit to switch from the flow path leading to the steam generator to the bypass flow path, controls the second switching unit to switch from the bypass flow path to the flow path leading to the steam generator when the temperature of the second refrigerant detected by the second refrigerant temperature detecting unit is equal to or lower than a predetermined first threshold. With this configuration, the control unit can switch from the bypass flow path to the flow path leading to the steam generator by the second switching unit when the temperature of the second refrigerant detected by the second refrigerant temperature detecting unit is equal to or lower than the predetermined first threshold, so that the cooling operation can be started promptly after the temperature of the second refrigerant becomes equal to or lower than the predetermined first threshold.

[0016] In the cooling system according to the first aspect, the cooling system preferably includes a first cycle connecting flow path branched from a flow path between the evaporator and the compressor in the refrigeration cycle and joining a flow path between the heat exchanger and a suction port of the ejector in the ejector cycle; a first on-off valve provided in the first cycle connecting flow path and configured to fully open or close the first cycle connecting flow path; a second cycle connecting flow path branched from a flow path between the first branch portion and the second expansion valve in the ejector cycle and joining a flow path between the condenser and the first expansion valve in the refrigeration cycle; a second on-off valve provided in the second cycle connecting flow path and configured to fully open or close the second cycle connecting flow path; and a mixed refrigerant pressure detector for detecting the pressure of a mixed refrigerant in which the first refrigerant and the second refrigerant are mixed and discharged from a discharge port of the ejector. The control unit further includes a force detection unit and a control unit that controls operation of the compressor and opening and closing of the first and second on-off valves, and when the pressure value detected by the mixed refrigerant pressure detection unit is equal to or lower than a predetermined second threshold, the control unit stops the compressor and fully opens the first and second on-off valves to circulate the mixed refrigerant to the second condenser of the ejector cycle and the evaporator of the refrigeration cycle via the first cycle connecting flow path and the second cycle connecting flow path without passing through the first condenser and the heat exchanger, and when the pressure value detected by the mixed refrigerant pressure detection unit exceeds the predetermined second threshold, the control unit operates the compressor and fully closes the first and second on-off valves to circulate the mixed refrigerant to both the refrigeration cycle and the ejector cycle. With this configuration, when the pressure value of the mixed refrigerant discharged from the ejector discharge port, which correlates with the outside air temperature and the saturation temperature of the ejector discharge flow, is equal to or lower than a predetermined second threshold value, the compressor is stopped and the mixed refrigerant can be circulated to the second condenser of the ejector cycle and the evaporator of the refrigeration cycle via the first cycle connecting flow path and the second cycle connecting flow path, thereby further improving the energy-saving performance of the cooling system by stopping the compressor when cooling the object to be cooled.

[0017] In this case, preferably, the ejector cycle further includes a third condenser that heats the heating target by condensing the mixed refrigerant flowing out from the steam generator, a third expansion valve that is provided downstream of the third condenser and expands the mixed refrigerant, and a first switching unit that is provided between the steam generator and an inlet of the ejector and switches between a cooling operation in which all of the mixed refrigerant flowing out from the steam generator flows into the ejector and a cooling / heating operation in which a portion of the mixed refrigerant flowing out from the steam generator flows into the ejector and all but a portion of the mixed refrigerant flowing out from the steam generator flows into the third condenser, and the control unit stops the compressor and controls the first on-off valve and the second on-off valve when the pressure value detected by the mixed refrigerant pressure detection unit is equal to or lower than a predetermined second threshold in the cooling / heating operation switched from the cooling operation by the first switching unit. and the second on-off valve are fully opened, so that a portion of the mixed refrigerant flowing out from the steam generator is circulated to the second condenser of the ejector cycle and the evaporator of the refrigeration cycle via the first cycle connecting flow path and the second cycle connecting flow path without passing through the first condenser and the heat exchanger, and the remaining portion of the mixed refrigerant flowing out from the steam generator is circulated to the third condenser without passing through the ejector and the heat exchanger, and is caused to flow into a flow path between the discharge port of the ejector and the second condenser via the third expansion valve, and when the pressure value detected by the mixed refrigerant pressure detection unit exceeds a predetermined second threshold, the compressor is operated, and the first on-off valve and the second on-off valve are fully closed, so that the mixed refrigerant is circulated to each of the refrigeration cycle and the ejector cycle including the third condenser. With this configuration, when the pressure value of the mixed refrigerant discharged from the ejector discharge port, which correlates with the outside air temperature and the saturation temperature of the ejector discharge flow, is equal to or lower than a predetermined second threshold value, the compressor is stopped, and the mixed refrigerant is circulated to the second condenser of the ejector cycle and the evaporator of the refrigeration cycle via the first cycle connecting flow path and the second cycle connecting flow path, and the mixed refrigerant is also circulated to the third condenser.Therefore, when cooling an object to be cooled and heating an object to be heated, the energy-saving performance of the cooling system can be further improved by stopping the compressor.

[0018] The cooling system according to the first aspect preferably further includes a control unit that controls the aperture of the second expansion valve and the amount of second refrigerant delivered by the liquid feed pump based on the relationship between the pressure of the second refrigerant discharged from the discharge port of the ejector, the pressure of the second refrigerant introduced into the suction port of the ejector, and the pressure of the second refrigerant introduced into the inlet of the ejector. With this configuration, the control unit controls the aperture of the second expansion valve so that the suction flow of the ejector reaches the saturation temperature obtained based on the relationship between the pressures of the second refrigerants, and controls the amount of second refrigerant delivered by the liquid feed pump so that the driving flow of the ejector reaches the saturation temperature obtained based on the relationship between the pressures of the second refrigerants. This makes it possible to achieve both improved condensation efficiency in the heat exchanger by increasing the refrigerant flow rate in the ejector and improved energy conservation performance in the cooling system.

[0019] A vending machine according to a second aspect of the present invention includes a refrigeration cycle, an ejector cycle, a heat exchanger provided between the refrigeration cycle and the ejector cycle, and a storage compartment for storing commodities. The refrigeration cycle includes a compressor for compressing a first refrigerant, a first condenser connected in series downstream of the compressor for condensing the first refrigerant, a condensing section including a heat exchanger for cooling the first refrigerant by exchanging heat between the first refrigerant and a second refrigerant circulating through the ejector cycle, a first expansion valve for expanding the first refrigerant flowing out of the condensing section, and an evaporator for evaporating the first refrigerant expanded by the first expansion valve to cool the air in the storage compartment. The ejector cycle includes a second condenser for condensing the second refrigerant, and a second condenser provided downstream of the second condenser. a first branching section configured to expand a portion of the second refrigerant that flows out of the second condenser and through the first branching section; a second expansion valve that expands a portion of the second refrigerant that flows out of the second condenser and through the first branching section; a heat exchanger that evaporates the second refrigerant by exchanging heat between the second refrigerant expanded by the second expansion valve and the first refrigerant; a liquid feed pump that feeds all but the portion of the second refrigerant that flows out of the second condenser and through the first branching section; a vapor generator that evaporates the second refrigerant fed from the liquid feed pump using an external heat source; and an ejector that introduces the second refrigerant evaporated in the vapor generator from an inlet as a driving flow, introduces the second refrigerant that flows out of the heat exchanger from a suction port as a suction flow, and discharges the second refrigerant, a mixture of the driving flow and the suction flow, from a discharge port, thereby sending the second refrigerant to the second condenser.

[0020] A vending machine according to a second aspect of the present invention includes a heat exchanger disposed between a refrigeration cycle and an ejector cycle, as described above. The ejector cycle includes a vapor generator that evaporates a second refrigerant using an external heat source, and an ejector that introduces the second refrigerant evaporated by the vapor generator through an inlet as a driving flow, introduces the second refrigerant flowing out of the heat exchanger through a suction port, and discharges the second refrigerant, a mixture of the driving flow and the suction flow, through a discharge port, thereby sending the second refrigerant to a second condenser. This allows the ejector cycle to lower the temperature of the second refrigerant in the heat exchanger below the ambient temperature, and heat exchange occurs between the second refrigerant and the first refrigerant in the refrigeration cycle, evaporating the second refrigerant and condensing the first refrigerant. This lowers the condensing temperature of the first condenser compared to a vending machine without an ejector cycle, thereby reducing the power consumption of the compressor. As a result, a vending machine can be provided that maintains the cooling performance of the refrigeration cycle while reducing the power consumption of the compressor, thereby improving the energy-saving performance of the cooling system. [Effects of the Invention]

[0021] According to the present invention, as described above, it is possible to provide a cooling system and a vending machine that can improve the energy-saving performance of the cooling system by reducing the power consumption of the compressor while maintaining the cooling performance of the refrigeration cycle. [Brief explanation of the drawings]

[0022] [Figure 1] 1 is a refrigerant circuit diagram showing a schematic configuration of a cooling system according to a first embodiment. [Figure 2] FIG. 2 is a refrigerant circuit diagram showing the flow of refrigerant when CCC operation is performed in the refrigerant circuit diagram shown in FIG. [Figure 3] FIG. 2 is a refrigerant circuit diagram showing the flow of refrigerant when HCC operation is performed in the refrigerant circuit diagram shown in FIG. 1. [Figure 4] FIG. 2 is a diagram for explaining the characteristics of each of a plurality of refrigerants. [Figure 5] 10 is a graph showing characteristics of the flow rate ratio, the amount of suction cooling, and the power consumption of the cooling system, with the saturation temperature of the suction flow of the ejector as a parameter. [Figure 6] 10 is a flow rate ratio characteristic map showing the relationship between the driving flow and the suction flow in the ejector. [Figure 7] FIG. 6 is a refrigerant circuit diagram showing a schematic configuration of a cooling system according to a second embodiment. [Figure 8] FIG. 8 is a refrigerant circuit diagram showing the flow of refrigerant when a cooling operation is performed in the refrigerant circuit diagram shown in FIG. 7. [Figure 9] FIG. 8 is a refrigerant circuit diagram showing the flow of refrigerant when a heating operation is performed in the refrigerant circuit diagram shown in FIG. 7. [Figure 10] FIG. 8 is a refrigerant circuit diagram showing the flow of refrigerant when a heating operation and a cooling operation using only a refrigeration cycle are performed in the refrigerant circuit diagram shown in FIG. 7. [Figure 11] FIG. 4 is a ph diagram for explaining the state of the refrigerant in the heating flow path that does not pass through the ejector in the cooling and heating operation according to the first embodiment. [Figure 12] FIG. 10 is a pH diagram for explaining the state of the refrigerant in the heating flow path that does not pass through the ejector in the heating operation according to the second embodiment. [Figure 13] FIG. 10 is a refrigerant circuit diagram showing a schematic configuration of a cooling system according to a third embodiment. [Figure 14] FIG. 14 is a refrigerant circuit diagram showing the flow of refrigerant when operation is performed via a bypass flow path in the refrigerant circuit diagram shown in FIG. 13. [Figure 15] 1 is a graph showing the relationship between the saturation temperature of the suction flow of the ejector and the thermal COP of the ejector cycle. [Figure 16] 1 is a graph showing the relationship between the saturation temperature of the discharge flow of the ejector and the thermal COP of the ejector cycle. [Figure 17] FIG. 10 is a refrigerant circuit diagram showing a schematic configuration of a cooling system according to a fourth embodiment. [Figure 18]FIG. 18 is a refrigerant circuit diagram showing the flow of refrigerant when a refrigeration cycle and an ejector cycle combined operation is performed in CCC operation in the refrigerant circuit diagram shown in FIG. 17. [Figure 19] FIG. 18 is a refrigerant circuit diagram showing the flow of refrigerant when the ejector cycle is operated alone in CCC operation in the refrigerant circuit diagram shown in FIG. 17. [Figure 20] FIG. 18 is a refrigerant circuit diagram showing the flow of refrigerant when a refrigeration cycle and an ejector cycle combined operation is performed in HCC operation in the refrigerant circuit diagram shown in FIG. 17. [Figure 21] FIG. 18 is a refrigerant circuit diagram showing the flow of refrigerant when the ejector cycle is operated alone in HCC operation in the refrigerant circuit diagram shown in FIG. 17. DETAILED DESCRIPTION OF THE INVENTION

[0023] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described with reference to the accompanying drawings.

[0024] [First embodiment] (Vending machine configuration) A vending machine 200 including a cooling system 100 according to a first embodiment will be described with reference to FIGS. 1 to 6. FIG.

[0025] (Cooling system) The cooling system 100 cools or heats air by circulating a refrigerant. The air cooled by the cooling system 100 is used to cool the space within the storage room 4 or the goods stored in the storage room 4. The air heated by the cooling system 100 is used to heat the space within the storage room 4 or the goods stored in the storage room 4. The cooling system 100 includes a refrigeration cycle 1, an ejector cycle 2, and a heat exchanger 3 provided across the refrigeration cycle 1 and the ejector cycle 2.

[0026] The vending machine 200 includes a cooling system 100, a storage compartment 4, and a solar heat recovery device 5. As shown in FIG. 1, the vending machine 200 includes multiple storage compartments 4, including a first storage compartment 41, a second storage compartment 42, and a third storage compartment 43. Each of the multiple storage compartments 4 is configured to store products. The multiple storage compartments 4 are cooled or heated by the cooling system 100. The first storage compartment 41 is a dual-purpose storage compartment that can switch between cooling and heating. The second storage compartment 42 and the third storage compartment 43 are dedicated to cooling. The first storage compartment 41 includes an evaporator 13 of the refrigeration cycle 1 and a third condenser 26 of the ejector cycle 2. The first storage compartment 41 also includes a heater 7 for auxiliary heating in case the first storage compartment 41 is not heated enough. The second storage compartment 42 includes the evaporator 13 of the refrigeration cycle 1. In the third storage compartment 43, the evaporator 13 of the refrigeration cycle 1 is arranged.

[0027] The refrigeration cycle 1 includes a compressor 10, a condenser 11, a first expansion valve 12, and an evaporator 13. In the refrigeration cycle 1, a first refrigerant circulates.

[0028] The compressor 10 is configured to compress a first refrigerant. Specifically, the compressor 10 compresses a low-pressure refrigerant vapor into a high-pressure gas-phase refrigerant.

[0029] The condenser section 11 includes a first condenser 14 and a heat exchanger 3. The first condenser 14 and the heat exchanger 3 are connected in series downstream of the compressor 10. In the condenser section 11, the heat exchanger 3 is disposed downstream of the first condenser 14 and upstream of the first expansion valve 12.

[0030] The first condenser 14 is configured to condense a portion of the high-pressure refrigerant vapor compressed in the compressor 10 into a high-pressure liquid-phase refrigerant. A blower fan 14a is provided near the first condenser 14. In the first condenser 14, heat of the refrigerant is removed by air sent by the blower fan 14a.

[0031] The heat exchanger 3 is configured on the refrigeration cycle 1 side to condense the gas-liquid two-phase first refrigerant flowing out from the first condenser 14 into a high-pressure liquid-phase refrigerant. The heat exchanger 3 condenses the first refrigerant by exchanging heat between the first refrigerant and the second refrigerant circulating through the ejector cycle 2.

[0032] The first expansion valve 12 is configured to reduce the pressure and expand the high-pressure liquid-phase refrigerant flowing out from the condensation section 11 including the first condenser 14 and the heat exchanger 3 to produce a low-pressure, low-temperature two-phase gas-liquid refrigerant. A plurality of first expansion valves 12 are provided. The first expansion valves 12 are arranged upstream of each of the plurality of evaporators 13.

[0033] The evaporator 13 is configured to cool the air in the storage compartment 4, which is the object to be cooled, by evaporating the first refrigerant expanded by the first expansion valve 12. In the evaporator 13, the low-pressure, low-temperature, gas-liquid two-phase first refrigerant flowing out from the first expansion valve 12 becomes a low-pressure gas-phase refrigerant, which absorbs heat from the air in the storage compartment supplied by a fan (not shown). As a result, the products in the storage compartment 4 are cooled by the air that has absorbed the heat.

[0034] The refrigeration cycle 1 includes a cooling flow path that runs from the compressor 10, through the first condenser 14, the heat exchanger 3, the first expansion valve 12, and the evaporator 13 in this order, and then returns to the compressor 10.

[0035] The ejector cycle 2 includes a second condenser 20, a storage unit 21, a second expansion valve 22, a heat exchanger 3, a liquid pump 23, a steam generator 24, an ejector 25, a third condenser 26, a third expansion valve 27, and a first switching unit 28. In the ejector cycle 2, a second refrigerant circulates.

[0036] The second condenser 20 is configured to condense the refrigerant vapor discharged from the discharge port 25c of the ejector 25 into a liquid-phase refrigerant. A blower fan 20a is provided near the second condenser 20. Heat is removed from the refrigerant in the second condenser 20 by air sent by the blower fan 20a. A medium-pressure refrigerant vapor, which is a mixture of a high-pressure, high-temperature driving flow and a low-pressure, low-temperature suction flow, is discharged from the discharge port 25c of the ejector 25. That is, the pressure (low pressure) of the second refrigerant introduced from the suction port 25b of the ejector 25 is less than the pressure (medium pressure) of the second refrigerant discharged from the discharge port 25c of the ejector 25 and less than the pressure (high pressure) of the second refrigerant introduced from the inlet 25a of the ejector 25.

[0037] The reservoir 21 is configured to store the second refrigerant condensed by the second condenser 20. The reservoir 21 is provided downstream of the second condenser 20 and upstream of the first branch portion 29.

[0038] First branching section 29 is provided in the flow path downstream of storage section 21. At first branching section 29, the second refrigerant that has flowed out of storage section 21 branches into a flow path through which the second refrigerant that has flowed out of storage section 21 flows into second expansion valve 22, and a flow path through which the second refrigerant that has flowed out of storage section 21 flows into liquid feed pump 23.

[0039] The second expansion valve 22 is configured to decompress and expand a portion of the medium-pressure liquid-phase refrigerant that flows out of the storage section 21 and flows in via the first branch section 29. The second expansion valve 22 expands the medium-pressure liquid-phase refrigerant that has flowed in, converting it into a low-pressure, low-temperature two-phase gas-liquid refrigerant. The second expansion valve 22 is provided downstream of the first branch section 29 and upstream of the heat exchanger 3.

[0040] The heat exchanger 3 is configured on the ejector cycle 2 side to evaporate the gas-liquid two-phase second refrigerant flowing out from the second expansion valve 22 to convert it into a low-pressure gas-phase refrigerant. The heat exchanger 3 evaporates the second refrigerant by exchanging heat between the second refrigerant expanded by the second expansion valve 22 and the first refrigerant circulating through the refrigeration cycle 1. The heat exchanger 3 is provided downstream of the second expansion valve 22 and upstream of the ejector suction port 25b.

[0041] Liquid feed pump 23 is configured to feed all but a portion of the second refrigerant that flows out of storage section 21 and flows in via first branch section 29. The second refrigerant fed by liquid feed pump 23 flows into steam generator 24. Liquid feed pump 23 is provided downstream of first branch section 29 and upstream of steam generator 24.

[0042] The steam generator 24 is configured to evaporate the second refrigerant sent from the liquid feed pump 23 using an external heat source. An example of the external heat source is solar heat. The steam generator 24 is configured to evaporate the second refrigerant sent from the liquid feed pump 23 using solar heat as a heat source. The external heat source is not limited to solar heat and may be, for example, exhaust heat from cogeneration. The steam generator 24 is disposed in the heat medium stored in the heat storage tank 51 of the solar heat recovery device 5. When the second refrigerant flows through the steam generator 24, the second refrigerant exchanges heat with the heat medium and receives heat from the heat medium, thereby evaporating the second refrigerant. The steam generator 24 is disposed downstream of the liquid feed pump 23 and upstream of the first switching unit 28.

[0043] Ejector 25 is configured to introduce the second refrigerant evaporated in steam generator 24 as a driving flow from inlet 25a, introduce the second refrigerant flowing out from heat exchanger 3 as a suction flow from suction port 25b, and discharge the second refrigerant, which is a mixture of the driving flow and the suction flow, from discharge port 25c, thereby sending the second refrigerant to second condenser 20.

[0044] Ejector 25 includes inlet 25a, suction port 25b, and discharge port 25c. High-pressure gas-phase refrigerant flowing out from steam generator 24 is supplied to inlet 25a as a driving flow via first switching unit 28. Ejector 25 draws low-pressure gas-phase refrigerant in the flow path between heat exchanger 3 and suction port 25b as a suction flow from suction port 25b due to a drop in static pressure caused by the driving flow. The driving flow supplied to inlet 25a and the suction flow supplied to suction port 25b are mixed, and the mixed gas-phase refrigerant is pressurized by a diffuser and then discharged from discharge port 25c. That is, medium-pressure gas-phase refrigerant, which is between high pressure and low pressure, is discharged from discharge port 25c of ejector 25.

[0045] The third condenser 26 is configured to heat the air in the storage compartment 4, which is the heating target, by condensing the second refrigerant evaporated in the steam generator 24. In the third condenser 26, the high-pressure, high-temperature gas-phase second refrigerant flowing out from the steam generator 24 becomes a high-pressure liquid-phase refrigerant, and heat is absorbed by the air in the storage compartment supplied by a fan (not shown). As a result, the products in the storage compartment 4 are heated by the air that has absorbed the heat. The third condenser 26 is provided in the heating flow path. The heating flow path is a flow path that branches off from the first switching unit 28 and merges with the flow path between the discharge port 25c of the ejector 25 and the second condenser 20.

[0046] The third expansion valve 27 is configured to expand the high-pressure liquid-phase refrigerant flowing out from the third condenser 26 to form a medium-pressure liquid-phase refrigerant. The third expansion valve 27 is provided downstream of the third condenser 26 in the heating flow path.

[0047] First switching unit 28 is configured to switch between a cooling operation in which all of the second refrigerant flowing out of steam generator 24 flows into inlet 25a of ejector 25 and a cooling / heating operation in which a portion of the second refrigerant flowing out of steam generator 24 flows into inlet 25a of ejector 25 and all but a portion of the second refrigerant flowing out of steam generator 24 flows into third condenser 26. That is, first switching unit 28 is configured to switch between two directions: a flow path connecting steam generator 24 and first switching unit 28 and a cooling flow path, and three directions: a flow path connecting steam generator 24 and first switching unit 28, a cooling flow path, and a heating flow path. First switching unit 28 is provided between steam generator 24 and inlet 25a of ejector 25. First switching unit 28 is, for example, a three-way valve.

[0048] The ejector cycle 2 includes a cooling flow path and a heating flow path. The cooling flow path is composed of a flow path that runs from the discharge port 25c of the ejector 25, passes through the second condenser 20 and the storage unit 21 in this order, and flows through the liquid feed pump 23, the steam generator 24, and the first switching unit 28 in this order via the first branching unit 29, before flowing into the inlet 25a of the ejector 25. Also, the heating flow path runs from the first switching unit 28, passes through the third condenser 26 and the third expansion valve 27 in this order, and merges with the flow path between the discharge port 25c of the ejector 25 and the second condenser 20.

[0049] Here, the cooling system 100 is configured to cool or heat (warm) the products stored in the storage compartment 4. Specifically, the cooling system 100 is configured to be capable of performing CCC operation (Cold / Cold / Cold operation) and HCC operation (Hot / Cold / Cold operation). In this specification, CCC operation refers to an operation in which the interior air of all of the first storage compartment 41, the second storage compartment 42, and the third storage compartment 43 is cooled. Also, in this specification, HCC operation refers to an operation in which the interior air of the first storage compartment 41 is heated and the interior air of the second storage compartment 42 and the third storage compartment 43 is cooled.

[0050] 2, in CCC operation, the first switching unit 28 is switched to cooling operation. That is, in CCC operation, the first switching unit 28 causes all of the second refrigerant flowing out from the steam generator 24 to flow into the inlet 25a of the ejector 25. In addition, the third expansion valve 27 is fully closed, and the on-off valve 15 provided in the flow path between the first storage compartment 41 and the compressor 10 is fully open.

[0051] As a result, in the refrigeration cycle 1, the first refrigerant flows from the compressor 10 through the first condenser 14, the heat exchanger 3, the first expansion valve 12, and the evaporators 13 of the first storage compartment 41, the second storage compartment 42, and the third storage compartment 43 in this order, and returns to the compressor 10.

[0052] In the ejector cycle 2, the second refrigerant flows from the discharge port 25c of the ejector 25 through the second condenser 20 and the storage section 21 in this order, and a portion of the second refrigerant passes through the second expansion valve 22 and the heat exchanger 3 in this order via the first branch section 29 before flowing into the suction port 25b of the ejector 25, while the remaining portion of the second refrigerant passes through the liquid delivery pump 23, the steam generator 24, and the first switching section 28 in this order via the first branch section 29 before flowing into the inlet 25a of the ejector 25.

[0053] 3, in the HCC operation, first switching unit 28 is switched to the cooling / heating operation. In the cooling / heating operation, ejector cycle 2 is used to heat the air inside first storage compartment 41 without using ejector 25, while simultaneously assisting in the cooling of the air inside second storage compartment 42 and third storage compartment 43 using ejector 25. In the HCC operation, first switching unit 28 causes a portion of the second refrigerant flowing out of steam generator 24 to flow into inlet 25a of ejector 25, and causes the remaining portion of the second refrigerant flowing out of steam generator 24 to flow into third condenser 26. In addition, the opening of third expansion valve 27 is controlled by control unit 6 to allow the second refrigerant to flow, and on-off valve 15, provided in the flow path between first storage compartment 41 and compressor 10, is fully closed.

[0054] As a result, in the refrigeration cycle 1, the first refrigerant flows from the compressor 10 through the first condenser 14, the heat exchanger 3, the first expansion valve 12, and the evaporators 13 of the second storage compartment 42 and the third storage compartment 43, excluding the evaporator 13 of the first storage compartment 41, in that order, and then returns to the compressor 10.

[0055] In the ejector cycle 2, a portion of the second refrigerant flowing out from the steam generator 24 flows into the inlet 25a of the ejector 25 via the first switching unit 28, and then flows from the discharge port 25c of the ejector 25 through the second condenser 20 and the storage unit 21 in this order. Also, a portion of the second refrigerant flows through the second expansion valve 22 and the heat exchanger 3 in this order via the first branching unit 29 and flows into the suction port 25b of the ejector 25. All the second refrigerant except for the portion of the second refrigerant flows through the liquid delivery pump 23, the steam generator 24, and the first switching unit 28 in this order via the first branching unit 29 and flows into the inlet 25a of the ejector 25. In addition, all but a portion of the second refrigerant flowing out from the steam generator 24 flows through the third condenser 26 and the third expansion valve 27 in that order via the first switching unit 28, and flows into the flow path between the discharge port 25c of the ejector 25 and the second condenser 20.

[0056] In CCC operation, the air and the products inside the first storage compartment 41 are cooled by the evaporation of the first refrigerant in the evaporator 13. In addition, in HCC operation, the air and the products inside the first storage compartment 41 are heated by the condensation of the second refrigerant in the third condenser 26.

[0057] (Solar heat recovery equipment) The solar heat recovery device 5 includes a heat collector 50 , a heat storage tank 51 , and a circulation pump 52 .

[0058] The solar collector 50 is configured to collect solar heat and heat a heat medium. The heat medium is, for example, water. When the heat medium passes through the solar collector 50, it is heated by radiant heat from the sun. The solar collector 50 is installed at an angle with respect to the vertical direction.

[0059] The heat storage tank 51 is configured to store the heat medium heated in the heat collector 50. The heat storage tank 51 is, for example, a tank. The heat storage tank 51 is provided with the steam generator 24, which performs heat exchange between the heat medium and the second refrigerant.

[0060] The circulation pump 52 is configured to circulate the heat medium between the heat collector 50 and the heat storage tank 51. The circulation pump 52 is provided downstream of the heat storage tank 51 and upstream of the heat collector 50.

[0061] (First and second refrigerants) The refrigeration cycle 1 and the ejector cycle 2 form refrigerant flow paths that are different from each other. That is, the refrigeration cycle 1 and the ejector cycle 2 are configured independently from each other. Therefore, different types of refrigerants can be used as the first refrigerant of the refrigeration cycle 1 and the second refrigerant of the ejector cycle 2.

[0062] The first refrigerant can be selected appropriately depending on the temperature range of the object to be cooled. In this embodiment, the object to be cooled is the air inside the storage compartment 4 of the vending machine 200. As an example, R1234yf is used as the first refrigerant.

[0063] The second refrigerant may be the same as the first refrigerant, but it is preferable to use a low-pressure refrigerant with a higher standard boiling point (boiling point at 1 atmospheric pressure) than the first refrigerant. As an example, R1336mzzE is used as the second refrigerant. Here, the low-pressure refrigerant refers to a refrigerant with a relatively high standard boiling point (boiling point at 1 atmospheric pressure) and a relatively low differential pressure during operation. The power of the liquid feed pump 23 in the ejector cycle 2 is based on the amount of pressure increase, which is the difference between the drive pressure and discharge pressure of the ejector 25. By using a low-pressure refrigerant with a higher standard boiling point than the first refrigerant and a low differential pressure during operation, the amount of pressure increase of the liquid feed pump 23 in the ejector cycle 2 can be reduced. Therefore, as shown in FIG. 4, when R1336mzzE or R1234zeE is used as the second refrigerant, the COP (Coefficient of Performance), which represents the operating efficiency of the ejector cycle 2, can be increased.

[0064] (Control of the opening of the second expansion valve and the amount of liquid sent by the liquid sending pump by the control unit) The cooling system 100 further includes an inlet pressure detection unit 60, an inlet pressure detection unit 61, an outlet pressure detection unit 62, and a control unit 6.

[0065] The inlet pressure detection unit 60 is configured to detect the pressure of the second refrigerant introduced into the inlet 25a of the ejector 25. The suction port pressure detection unit 61 is configured to detect the pressure of the second refrigerant introduced into the suction port 25b of the ejector 25. The discharge port pressure detection unit 62 is configured to detect the pressure of the second refrigerant discharged from the discharge port 25c of the ejector 25.

[0066] The control unit 6 includes a CPU (Central Processing Unit). The control unit 6 is configured to control the opening degree of the second expansion valve 22 and the amount of the second refrigerant sent by the liquid sending pump 23, based on the relationship among the pressure of the second refrigerant discharged from the discharge port 25c of the ejector 25, the pressure of the second refrigerant introduced into the suction port 25b of the ejector 25, and the pressure of the second refrigerant introduced into the inlet 25a of the ejector 25.

[0067] Next, the operation of the liquid pump 23 and the control of the opening degree of the second expansion valve 22 by the control unit 6 will be described with reference to FIGS.

[0068] 5 is a graph showing the characteristics of the flow rate ratio (suction flow rate / driving flow rate), suction cooling amount, and power consumption of the cooling system 100, with the saturation temperature Ts of the suction flow of the ejector 25 as a parameter at an outside air temperature of 37°C. Here, the ejector 25 has a characteristic that the refrigerant flow rate decreases when the suction pressure is lowered (the amount of pressure increase (discharge pressure Pd - suction pressure Ps) is increased). If the refrigerant flow rate in the ejector 25 decreases, there is a possibility that the amount of condensation heat radiation on the cooling cycle side of the heat exchanger 3 will not be sufficient.

[0069] As shown in Fig. 5, by increasing the suction pressure of the ejector 25 (reducing the amount of pressure increase) and increasing the flow rate ratio of the ejector 25, the suction cooling capacity of the ejector 25 (i.e., the amount of heat dissipated from the second condenser 20 in the ejector cycle 2) increases, thereby reducing the power consumption of the cooling system 100. However, when the saturation temperature Ts of the suction flow of the ejector 25 exceeds a threshold, the suction capacity of the ejector 25 tends to saturate due to, for example, the second refrigerant that has not fully evaporated flowing in through the suction port 25b of the ejector 25 (the region indicated as suction two-phase in Fig. 5). That is, as shown in Fig. 5, it can be seen that there is a suction saturation temperature Ts (27°C in Fig. 5) that minimizes the power consumption of the entire cooling system 100.

[0070] Since the discharge pressure Pd correlates with the condensation temperature of the second condenser 20 (i.e., the outside air temperature), the control unit 6 can obtain the optimal suction pressure Ps by obtaining the optimal suction flow saturation temperature Ts shown in Fig. 5 from the outside air temperature. The control unit 6 is configured to obtain the pressures detected by the discharge port pressure detection unit 62 and the suction port pressure detection unit 61, and to control the opening of the second expansion valve 22 so that the suction flow saturation temperature Ts of the ejector 25 becomes the optimal suction flow saturation temperature Ts (i.e., the optimal pressure increase amount Pd-Ps) obtained in advance for each rotation speed of the compressor 10 of the refrigeration cycle 1.

[0071] FIG. 6 is a flow rate ratio characteristic map showing the relationship between the driving flow and the suction flow in the ejector 25 optimized for the vending machine 200. Specifically, FIG. 6 is a contour map showing the flow rate ratio (suction flow rate / driving flow rate) of the ejector 25, with the horizontal axis representing the ratio of the discharge pressure Pd of the second refrigerant discharged from the discharge port 25c of the ejector 25 to the suction pressure Ps of the second refrigerant introduced into the suction port 25b of the ejector 25, and the vertical axis representing the ratio of the driving pressure Pg of the second refrigerant introduced into the inlet 25a of the ejector 25 to the discharge pressure Pd. The thick line connecting the peaks of the equal flow rate ratio curves in the flow rate ratio characteristic map represents the optimal driving pressure ratio (Pg / Pd) for obtaining the maximum flow rate ratio at the desired suction pressure ratio Pd / Ps (∝ pressure increase amount Pd-Ps). The flow rate ratio characteristic map differs depending on the size of the ejector 25, the type of refrigerant, etc., and is therefore obtained in advance by simulation. As an example, the thick line connecting the peaks of the equal flow rate ratio curves of the flow rate ratio characteristic map is expressed by an approximate formula such as the following formula (1).

number

[0072] As described above, the control unit 6 acquires the discharge pressure Pd and the optimal suction pressure Ps. Therefore, the control unit 6 can acquire the optimal driving pressure Pg by acquiring the optimal driving pressure ratio (Pg / Pd) for obtaining the maximum flow rate ratio from the flow rate ratio characteristic map based on the ratio between the discharge pressure Pd and the suction pressure Ps. The control unit 6 is configured to acquire the pressures detected by the suction port pressure detection unit 61 and the inlet pressure detection unit 60, and to control the pressurization of the second refrigerant by the liquid feed pump 23 so that the saturation temperature of the driving flow of the ejector 25 becomes the optimal driving pressure Pg for obtaining the maximum flow rate ratio.

[0073] (Effects of the first embodiment) In the first embodiment, the following effects can be obtained.

[0074] As described above, the first embodiment includes a heat exchanger 3 provided across the refrigeration cycle 1 and the ejector cycle 2. The ejector cycle 2 includes a vapor generator 24 that evaporates a second refrigerant using an external heat source, and an ejector 25 that introduces the second refrigerant evaporated in the vapor generator 24 as a driving flow through an inlet 25a, introduces the second refrigerant flowing out of the heat exchanger 3 as a suction flow through an inlet 25b, and discharges the second refrigerant, a mixture of the driving flow and the suction flow, from an outlet 25c, thereby sending the second refrigerant to the second condenser 20. This allows the ejector cycle 2 to lower the temperature of the second refrigerant in the heat exchanger 3 below the ambient temperature, and heat exchange between the second refrigerant and the first refrigerant in the refrigeration cycle 1 is performed in the heat exchanger 3, thereby evaporating the second refrigerant and condensing the first refrigerant. This allows the condensation temperature of the first condenser 14 to be lower than in a case where the ejector cycle 2 is not used, thereby reducing the power consumption of the compressor 10. As a result, the energy saving performance of the cooling system 100 can be improved by reducing the power consumption of the compressor 10 while maintaining the cooling performance of the refrigeration cycle 1.

[0075] Furthermore, in the first embodiment, as described above, in condensing section 11, heat exchanger 3 is disposed downstream of first condenser 14 and upstream of first expansion valve 12. This allows heat exchanger 3, which exchanges heat between the first refrigerant and a second refrigerant whose temperature is lower than the outside air temperature, to be disposed downstream of first condenser 14, which exchanges heat between the first refrigerant and the outside air, so that the first refrigerant can be condensed efficiently in condensing section 11.

[0076] In the first embodiment, as described above, the ejector cycle 2 includes the third condenser 26 that heats the heating target by condensing the second refrigerant flowing out from the steam generator 24, the third expansion valve 27 that is provided downstream of the third condenser 26 and expands the second refrigerant, and the third expansion valve 27 that is provided between the steam generator 24 and the inlet 25a of the ejector 25 and expands the second refrigerant. The third expansion valve 27 is provided between the steam generator 24 and the inlet 25a of the ejector 25 and operates in two modes: a cooling mode in which all of the second refrigerant flowing out from the steam generator 24 flows into the ejector 25, and a cooling mode in which only part of the second refrigerant flowing out from the steam generator 24 flows into the ejector 25. and a first switching unit 28 that switches between a cooling and heating operation and a cooling / heating operation in which a portion of the second refrigerant flowing from the first switching unit 28 flows into the ejector 25 and the remaining portion of the second refrigerant flowing out of the steam generator 24 flows into the third condenser 26. In the cooling / heating operation, the remaining portion of the second refrigerant flowing out of the first switching unit 28 does not flow through the ejector 25 and the heat exchanger 3 but flows through the third condenser 26, and also flows into a flow path between the discharge port 25c of the ejector 25 and the second condenser 20 via the third expansion valve 27. As a result, the object to be heated can be heated by condensing the second refrigerant vapor generated by an external heat source in the third condenser 26, without adopting a heat utilization method in which heat obtained when cooling the interior of the cooling chamber using the refrigeration cycle 1 is transferred to the heating chamber to heat the object to be heated in the heating chamber, and therefore the object to be heated can be heated efficiently. Furthermore, the second refrigerant flowing out of the third condenser 26 can be caused to flow into the flow path between the discharge port 25c of the ejector 25 and the second condenser 20 via the third expansion valve 27, so that the pressure of the second refrigerant discharged from the discharge port 25c of the ejector 25 can be made equal to the pressure of the second refrigerant flowing into the flow path between the discharge port 25c of the ejector 25 and the second condenser 20 via the third expansion valve 27. This makes it possible to suppress stress in the refrigerant piping due to a pressure difference between the pressure of the second refrigerant discharged from the discharge port 25c of the ejector 25 and the pressure of the second refrigerant flowing into the flow path between the discharge port 25c of the ejector 25 and the second condenser 20 via the third expansion valve 27.

[0077] In the first embodiment, as described above, the second refrigerant is a low-pressure refrigerant having a higher normal boiling point, which is the boiling point at 1 atmospheric pressure, than the first refrigerant. Because the refrigeration cycle 1 and the ejector cycle 2 have different refrigerant flow paths, different types of refrigerants can be used as the first refrigerant in the refrigeration cycle 1 and the second refrigerant in the ejector cycle 2. By using a low-pressure refrigerant with a higher normal boiling point than the first refrigerant and a low differential pressure during operation as the second refrigerant, the amount of pressure increase by the liquid feed pump 23 in the ejector cycle 2 can be reduced. This increases the COP, which represents the operating efficiency of the ejector cycle 2, thereby improving the energy-saving performance of the entire cooling system 100.

[0078] Furthermore, in the first embodiment, as described above, the cooling system 100 includes the control unit 6 that controls the aperture of the second expansion valve 22 and the amount of the second refrigerant sent by the liquid feed pump 23 based on the relationship between the pressure of the second refrigerant discharged from the discharge port 25c of the ejector 25, the pressure of the second refrigerant introduced into the suction port 25b of the ejector 25, and the pressure of the second refrigerant introduced into the inlet 25a of the ejector 25. As a result, the control unit 6 controls the aperture of the second expansion valve 22 so that the suction flow of the ejector 25 reaches the saturation temperature obtained based on the relationship between the pressures of the second refrigerant, and controls the amount of the second refrigerant sent by the liquid feed pump 23 so that the driving flow of the ejector 25 reaches the saturation temperature obtained based on the relationship between the pressures of the second refrigerant. This makes it possible to improve the condensation efficiency in the heat exchanger 3 by increasing the refrigerant flow rate in the ejector 25, and to improve the energy-saving performance of the cooling system 100.

[0079] [Second embodiment] Next, a vending machine 200 including a cooling system 100 according to a second embodiment of the present invention will be described with reference to Figures 7 to 12. Unlike the first embodiment described above, which includes a first switching unit 28 that switches between a cooling operation using the ejector cycle 2 in CCC operation and a cooling and heating operation using the ejector cycle 2 in HCC operation, the second embodiment will be described as including an example that is configured to include a second switching unit 30 that switches between a cooling operation via the ejector 25 using the ejector cycle 2 in HCC operation and a heating operation using the ejector cycle 2 without using the ejector 25. Note that the same components as those in the first embodiment will be assigned the same reference numerals, and their description will be omitted.

[0080] (Ejector cycle) As shown in FIG. 7 , the ejector cycle 2 includes a second switching unit 30. The second switching unit 30 is configured to switch between a cooling operation in which all of the second refrigerant flowing out of the steam generator 24 flows into the inlet 25a of the ejector 25 and a heating operation in which all of the second refrigerant flowing out of the steam generator 24 flows into the third condenser 26 without flowing into the inlet 25a of the ejector 25. That is, the second switching unit 30 is configured to switch between two directions: a cooling flow path connecting the steam generator 24 and the second switching unit 30 and the flow path, and a heating flow path connecting the steam generator 24 and the second switching unit 30. The second switching unit 30 is provided between the steam generator 24 and the inlet 25a of the ejector 25. The second switching unit 30 is, for example, a three-way valve.

[0081] As in the first embodiment, the cooling flow path is composed of a flow path that runs from the discharge port 25c of the ejector 25, passes through the second condenser 20 and the storage unit 21 in this order, passes through the liquid feed pump 23, the steam generator 24, and the second switching unit 30 in this order via the first branching unit 29, and flows into the inlet 25a of the ejector 25, and a flow path that runs through the second expansion valve 22 and the heat exchanger 3 in this order via the first branching unit 29, and flows into the suction port 25b of the ejector 25. Unlike the first embodiment, the heating flow path is a flow path that runs from the second switching unit 30, passes through the third condenser 26, and merges with the flow path between the second condenser 20 and the first branching unit 29. Specifically, the heating flow path is a flow path that runs from the second switching unit 30, passes through the third condenser 26, and merges with the flow path between the second condenser 20 and the storage unit 21.

[0082] (Cooling system) The cooling system 100 includes a cooling target temperature detection unit 63, a heating target temperature detection unit 64, and a control unit 6.

[0083] The cooling target temperature detection unit 63 is configured to detect the temperature of the cooling target. The cooling target temperature detection unit 63 is provided in each of the second storage compartment 42 and the third storage compartment 43. The cooling target temperature detection unit 63 is configured to detect the temperature in the second storage compartment 42 and the temperature in the third storage compartment 43 where the air inside the storage compartment is cooled during HCC operation.

[0084] The heating target temperature detection unit 64 is configured to detect the temperature of the heating target. The heating target temperature detection unit 64 is provided in the first storage compartment 41. The heating target temperature detection unit 64 is configured to detect the temperature inside the first storage compartment 41 where the air inside the storage compartment is heated during HCC operation.

[0085] The control unit 6 is configured to control switching between the cooling operation and the heating operation by the second switching unit 30 based on the temperature of the cooling object detected by the cooling object temperature detection unit 63 and the temperature of the heating object detected by the heating object temperature detection unit 64. Specifically, the control unit 6 is configured to control switching between the cooling operation and the heating operation by the second switching unit 30 in the HCC operation based on a cooling request based on the temperatures in the second storage compartment 42 and the third storage compartment 43 detected by the cooling object temperature detection unit 63 and a heating request based on the temperature in the first storage compartment 41 detected by the heating object temperature detection unit 64.

[0086] Furthermore, in the heating operation switched from the cooling operation by the second switching unit 30, the control unit 6 is configured to perform control so that the second refrigerant flowing out from the second switching unit 30 flows through the third condenser 26 without flowing through the ejector 25 and the heat exchanger 3, and so that the second refrigerant flowing out from the third condenser 26 flows into the flow path between the second condenser 20 and the first branch unit 29. Specifically, the control unit 6 is configured to perform control so that the second refrigerant flowing out from the second switching unit 30 and the second refrigerant flowing out from the third condenser 26 flows into the flow path between the second condenser 20 and the storage unit 21 in the heating operation.

[0087] (Switching control of second switching unit by control unit) <Cooling operation via ejector using ejector cycle> 8, the control unit 6 is configured to control the second switching unit 30 to switch to cooling operation when, during HCC operation, there is a cooling request based on either the temperature in the second storage compartment 42 or the temperature in the third storage compartment 43 detected by the cooling target temperature detection unit 63, and there is no heating request based on the temperature in the first storage compartment 41 detected by the heating target temperature detection unit 64. For example, the control unit 6 switches the second switching unit 30 to perform cooling operation when either the temperature in the second storage compartment 42 or the temperature in the third storage compartment 43 detected by the cooling target temperature detection unit 63 is 3°C or higher, and the temperature in the first storage compartment 41 detected by the heating target temperature detection unit 64 is 60°C or higher.

[0088] In this case, the ejector cycle 2 is used to assist in cooling the air inside the second storage compartment 42 and the third storage compartment 43 via the ejector 25. The second switching unit 30 causes all of the second refrigerant flowing out of the steam generator 24 to flow into the inlet 25a of the ejector 25.

[0089] In the refrigeration cycle 1, the first refrigerant flows from the compressor 10 through the first condenser 14, the heat exchanger 3, the first expansion valve 12, and the evaporators 13 of the second storage compartment 42 and the third storage compartment 43, excluding the evaporator 13 of the first storage compartment 41, in that order, and then returns to the compressor 10.

[0090] In addition, in the ejector cycle 2, all of the second refrigerant flowing out from the steam generator 24 flows into the inlet 25a of the ejector 25 via the second switching unit 30, and then flows from the discharge port 25c of the ejector 25 through the second condenser 20 and the storage unit 21 in this order, while part of the second refrigerant flows through the second expansion valve 22 and the heat exchanger 3 in this order via the first branching unit 29 and flows into the suction port 25b of the ejector 25, and all of the second refrigerant except for part of the second refrigerant flows through the liquid delivery pump 23, the steam generator 24, and the second switching unit 30 in this order via the first branching unit 29 and flows into the inlet 25a of the ejector 25.

[0091] <Heating operation without ejector using ejector cycle> 9, the control unit 6 is configured to control the second switching unit 30 to switch to heating operation when, during HCC operation, there is no cooling request based on both the temperatures in the second storage compartment 42 and the third storage compartment 43 detected by the cooling object temperature detection unit 63, and there is a heating request based on the temperature in the first storage compartment 41 detected by the heating object temperature detection unit 64. For example, when either the temperature in the second storage compartment 42 or the temperature in the third storage compartment 43 detected by the cooling object temperature detection unit 63 is less than 3°C, and the temperature in the first storage compartment 41 detected by the heating object temperature detection unit 64 is less than 60°C, the control unit 6 switches the second switching unit 30 to perform heating operation. The control unit 6 also controls the second expansion valve 22 to be fully closed.

[0092] In this case, the control unit 6 is configured to perform control to stop the operation of the compressor 10. As a result, the first refrigerant does not circulate in the refrigeration cycle 1.

[0093] In this case, the ejector cycle 2 is used to heat the air inside the first storage compartment 41 without using the ejector 25. The second switching unit 30 causes all of the second refrigerant that has flowed out of the steam generator 24 and evaporated using solar heat as a heat source to flow into the third condenser 26.

[0094] In the ejector cycle 2, all of the second refrigerant flowing out from the steam generator 24 flows through the third condenser 26 via the second switching unit 30 and enters the flow path between the second condenser 20 and the storage unit 21. Then, the second refrigerant flows through the storage unit 21 and the liquid feed pump 23 in this order, and then enters the steam generator 24.

[0095] <Heating operation using the ejector cycle without using an ejector / Cooling operation using only the refrigeration cycle> 10, the control unit 6 is configured to control switching to heating operation by the second switching unit 30 when, during HCC operation, there is a cooling request based on either the temperature in the second storage compartment 42 or the temperature in the third storage compartment 43 detected by the cooling target temperature detection unit 63, and there is a heating request based on the temperature in the first storage compartment 41 detected by the heating target temperature detection unit 64. For example, when either the temperature in the second storage compartment 42 or the temperature in the third storage compartment 43 detected by the cooling target temperature detection unit 63 is 3°C or higher, and the temperature in the first storage compartment 41 detected by the heating target temperature detection unit 64 is less than 60°C, the control unit 6 switches the second switching unit 30 to perform heating operation.

[0096] That is, when both a cooling request and a heating request are received in the HCC operation, the control unit 6 controls the second switching unit 30 to switch to the heating operation in order to prioritize the heating flow path in the ejector cycle 2. The control unit 6 also controls the compressor 10 to continue operating. As a result, the first refrigerant circulates in the refrigeration cycle 1, thereby cooling the air inside the second storage compartment 42 and the third storage compartment 43.

[0097] In this case, the air inside the first storage compartment 41 is heated using the ejector cycle 2 without using the ejector 25. The second switching unit 30 causes all of the second refrigerant flowing out from the steam generator 24 to flow into the third condenser 26. In addition, since the compressor 10 is operating, the first refrigerant is circulating in the refrigeration cycle 1.

[0098] (Comparison between heating operation of the second embodiment and cooling / heating operation of the first embodiment) FIG. 11 is a pH diagram illustrating the state of the refrigerant in the heating flow path that does not pass through ejector 25 during cooling / heating operation using ejector cycle 2 according to the first embodiment. For ease of explanation, FIG. 11 mainly illustrates the heating flow path. In the first embodiment, the second refrigerant condensed by third condenser 26 in first storage 41 (see E in FIG. 11 ) is expanded through third expansion valve 27 (see F in FIG. 11 ), merged with the second refrigerant discharged from discharge port 25c of ejector 25 (see G in FIG. 11 ), condensed in second condenser 20 (see H in FIG. 11 ), and pressurized by liquid feed pump 23 (see B in FIG. 11 ). That is, because the second refrigerant is decompressed by third expansion valve 27 and then pressurized by liquid feed pump 23, energy loss occurs as shown in the hatched area surrounded by EFGB in FIG. 11 .

[0099] In contrast, Fig. 12 is a pH diagram illustrating the state of the refrigerant during heating operation using the ejector cycle 2 according to the second embodiment without using the ejector 25. For ease of explanation, Fig. 12 mainly illustrates the heating flow path. In the second embodiment, the second refrigerant flows into the flow path between the second condenser 20 and the reservoir 21 without passing through the third expansion valve 27. That is, the second refrigerant is not pressurized by the liquid feed pump 23 after being depressurized by the third expansion valve 27, thereby suppressing energy loss.

[0100] The other configurations of the second embodiment are the same as those of the first embodiment.

[0101] (Effects of the second embodiment) In the second embodiment, the following effects can be obtained.

[0102] In the second embodiment, as described above, the ejector cycle 2 includes the third condenser 26 that heats a heating target by condensing the second refrigerant flowing out of the steam generator 24, and the third condenser 26 is provided between the steam generator 24 and the inlet 25a of the ejector 25. The ejector cycle 2 can perform a cooling operation in which all of the second refrigerant flowing out of the steam generator 24 flows into the inlet 25a of the ejector 25, and a heating operation in which all of the second refrigerant flowing out of the steam generator 24 flows into the third condenser 26 without flowing into the inlet 25a of the ejector 25. and a control unit 6 that controls switching between the cooling operation and the heating operation using the second switching unit 30. In the heating operation switched from the cooling operation by the second switching unit 30, the control unit 6 controls the second refrigerant that flows out from the second switching unit 30 to flow through the third condenser 26 without flowing through the ejector 25 and the heat exchanger 3, and controls the second refrigerant that flows out from the third condenser 26 to flow into the flow path between the second condenser 20 and the first branch unit 29. In this way, the control unit 6 switches between the cooling operation and the heating operation using the second switching unit 30 and causes the second refrigerant that flows out from the third condenser 26 to flow into the flow path between the second condenser 20 and the first branch unit 29. Therefore, it is not necessary to expand the second refrigerant using the third expansion valve 27 and then pressurize it using the liquid feed pump 23, as in the cooling and heating operation in which the cooling operation and the heating operation are performed in parallel. Therefore, the occurrence of energy loss can be suppressed, and the energy saving performance of the cooling system 100 can be further improved.

[0103] Furthermore, as described above, the second embodiment further includes a cooling target temperature detection unit 63 that detects the temperature of the cooling target, and a heating target temperature detection unit 64 that detects the temperature of the heating target, and the control unit 6 controls switching between the cooling operation and the heating operation using the second switching unit 30 based on the temperature of the cooling target detected by the cooling target temperature detection unit 63 and the temperature of the heating target detected by the heating target temperature detection unit 64. This allows the control unit 6 to easily switch between the cooling operation and the heating operation using the second switching unit 30 based on the temperature of the cooling target detected by the cooling target temperature detection unit 63 and the temperature of the heating target detected by the heating target temperature detection unit 64.

[0104] The other effects of the second embodiment are the same as those of the first embodiment.

[0105] [Third embodiment] Next, a vending machine 200 including a cooling system 100 according to a third embodiment of the present invention will be described with reference to Figures 13 and 14. Unlike the second embodiment, the third embodiment describes an example in which the ejector cycle 2 is configured to include a bypass flow path 33 and a third switching unit 32 that is provided in the second branching unit 31 and switches between the flow path leading to the steam generator 24 and the bypass flow path 33. Note that the same components as those in the second embodiment are designated by the same reference numerals, and descriptions thereof will be omitted.

[0106] (Ejector cycle) As shown in FIG. 13, the ejector cycle 2 includes a third switching unit 32 and a bypass flow path 33.

[0107] The third switching unit 32 is configured to switch between a flow path through which the second refrigerant sent from the liquid feed pump 23 flows into the steam generator 24 and a bypass flow path 33 into which the second refrigerant sent from the liquid feed pump 23 flows. That is, the third switching unit 32 is configured to switch between two directions: a flow path connecting the liquid feed pump 23 and the third switching unit 32 and a flow path connecting the steam generator 24 and the third switching unit 32, and a flow path connecting the liquid feed pump 23 and the third switching unit 32 and the bypass flow path 33. The third switching unit 32 is provided in the second branch unit 31 arranged in the flow path between the liquid feed pump 23 and the steam generator 24. The third switching unit 32 is, for example, a three-way valve.

[0108] The bypass flow path 33 is a flow path that branches off from the second branching part 31 and merges into a merging part provided in a flow path between the discharge port 25c of the ejector 25 and the second condenser 20. When the third switching part 32 switches to the bypass flow path 33, the second refrigerant circulates between the second condenser 20, the storage part 21, and the liquid feed pump 23 via the bypass flow path 33.

[0109] (Cooling system) The cooling system 100 includes a second refrigerant temperature detection unit 65 .

[0110] Second refrigerant temperature detection unit 65 is configured to detect the temperature of the second refrigerant stored in storage unit 21. Note that second refrigerant temperature detection unit 65 is not limited to a configuration that detects the temperature of the second refrigerant stored in storage unit 21, and may be configured to detect the temperature of the second refrigerant flowing out from second condenser 20, or may be configured to detect the temperature of the second refrigerant flowing into liquid feed pump 23, for example.

[0111] The control unit 6 is configured to switch from heating operation to cooling operation using the second switching unit 30, and to switch from the flow path leading to the steam generator 24 to the bypass flow path 33 using the third switching unit 32, thereby controlling the circulation of the second refrigerant between the second condenser 20, the storage unit 21, and the liquid delivery pump 23 via the bypass flow path 33.

[0112] In addition, the control unit 6 is configured to control the third switching unit 32 to switch from the flow path leading to the steam generator 24 to the bypass flow path 33, and then control the second switching unit 30 to switch from the bypass flow path 33 to the flow path leading to the steam generator 24 if the temperature of the second refrigerant detected by the second refrigerant temperature detection unit 65 is below a predetermined first threshold.

[0113] (Switching control of the third switching unit by the control unit) FIG. 14(a) is a diagram showing a heating operation using the ejector cycle 2 in HCC operation without using the ejector 25. Because there is no cooling request based on either the temperature in the second storage compartment 42 or the temperature in the third storage compartment 43 detected by the cooling target temperature detection unit 63, and there is a heating request based on the temperature in the first storage compartment 41 detected by the heating target temperature detection unit 64, the heating operation switched by the second switching unit 30 is being performed. The control unit 6 also stops the operation of the compressor 10. That is, FIG. 14(a) shows the same state as the heating operation using the ejector cycle 2 without using the ejector 25 shown in FIG. 9 in the second embodiment.

[0114] 14(a), when there is a cooling request based on either the temperature in the second storage compartment 42 or the temperature in the third storage compartment 43 detected by the cooling object temperature detection unit 63 and there is no longer a heating request based on the temperature in the first storage compartment 41 detected by the heating object temperature detection unit 64, the control unit 6 is configured to switch from heating operation to cooling operation using the second switching unit 30 and switch from the flow path leading to the steam generator 24 to the bypass flow path 33 using the third switching unit 32, thereby performing control to circulate the second refrigerant between the second condenser 20, the storage unit 21, and the liquid feed pump 23 via the bypass flow path 33, as shown in FIG. 14(b). The control unit 6 also starts operation of the compressor 10.

[0115] That is, the control unit 6 switches the second switching unit 30 from two directions, that is, the heating flow path and the flow path connecting the steam generator 24 and the second switching unit 30, to two directions, that is, the flow path connecting the steam generator 24 and the second switching unit 30 and the cooling flow path. Furthermore, the control unit 6 switches the third switching unit 32 from two directions, that is, the flow path connecting the liquid feed pump 23 and the third switching unit 32 and the flow path connecting the steam generator 24 and the third switching unit 32, to two directions, that is, the flow path connecting the liquid feed pump 23 and the third switching unit 32 and the bypass flow path 33. As a result, the second refrigerant circulates between the second condenser 20, the storage unit 21, and the liquid feed pump 23 via the bypass flow path 33.

[0116] Then, after controlling the third switching unit 32 to switch to the bypass flow path 33, the control unit 6 controls the second refrigerant to continue circulating between the second condenser 20, the storage unit 21, and the liquid delivery pump 23 via the bypass flow path 33 if the temperature of the second refrigerant detected by the second refrigerant temperature detection unit 65 exceeds a predetermined first threshold value.

[0117] Furthermore, after controlling the third switching unit 32 to switch to the bypass flow path 33, if the temperature of the second refrigerant detected by the second refrigerant temperature detection unit 65 is equal to or lower than a predetermined first threshold, the control unit 6 controls the second switching unit 30 to switch from the bypass flow path 33 to the flow path leading to the steam generator 24, as shown in FIG. 14(c). The predetermined first threshold is, for example, a temperature corresponding to the outside air temperature. However, the predetermined first threshold is not limited to a temperature corresponding to the outside air temperature as long as the temperature of the second refrigerant detected by the second refrigerant temperature detection unit 65 can activate the ejector 25. In other words, the temperature of the second refrigerant detected by the second refrigerant temperature detection unit 65 can be a temperature at which the ejector 25 can introduce a high-pressure second refrigerant from the inlet 25a, draw a low-pressure second refrigerant from the suction port 25b, and discharge a medium-pressure second refrigerant from the outlet 25c.

[0118] The control unit 6 performs cooling operation via the ejector 25 using the ejector cycle 2 in the HCC operation by switching the bypass flow path 33 to the flow path leading to the steam generator 24 using the second switching unit 30. The control unit 6 also continues to operate the compressor 10. That is, FIG. 14(c) is the same state as the cooling operation via the ejector 25 using the ejector cycle 2 shown in FIG. 8 in the second embodiment.

[0119] The other configurations of the third embodiment are the same as those of the second embodiment.

[0120] (Effects of the third embodiment) In the third embodiment, the following effects can be obtained.

[0121] As described above, in the third embodiment, the ejector cycle 2 further includes: a storage section 21 that is provided downstream of the second condenser 20 and upstream of the first branch section 29 and that stores the second refrigerant condensed by the second condenser 20; a second branch section 31 that is provided in a flow path between the liquid feed pump 23 and the steam generator 24; a bypass flow path 33 that branches from the second branch section 31 and merges into a junction that is provided in a flow path between the discharge port 25 c of the ejector 25 and the second condenser 20; and a third switching section 32 that is provided in the second branch section 31 and that switches between the flow path leading to the steam generator 24 and the bypass flow path 33. The control section 6 switches from the heating operation to the cooling operation using the second switching section 30 and switches from the flow path leading to the steam generator 24 to the bypass flow path 33 using the third switching section 32, thereby performing control to circulate the second refrigerant between the second condenser 20, the storage section 21, and the liquid feed pump 23 via the bypass flow path 33. As a result, when switching from heating operation to cooling operation by second switching unit 30, the temperature of the second refrigerant can be quickly lowered by circulating the second refrigerant between second condenser 20, storage unit 21, and liquid feed pump 23 via bypass flow path 33. Therefore, by introducing a high-pressure second refrigerant from inlet 25a, ejector 25 can quickly be brought into a state where low-pressure second refrigerant can be sucked from suction port 25b and medium-pressure second refrigerant can be discharged from discharge port 25c, thereby quickly starting the cooling operation.

[0122] Furthermore, as described above, the third embodiment further includes a second refrigerant temperature detection unit 65 that detects the temperature of any one of the second refrigerant flowing out from second condenser 20, the second refrigerant stored in storage unit 21, and the second refrigerant flowing into liquid feed pump 23. After controlling third switching unit 32 to switch from the flow path leading to steam generator 24 to bypass flow path 33, control unit 6 controls second switching unit 30 to switch from bypass flow path 33 to the flow path leading to steam generator 24 when the temperature of the second refrigerant detected by second refrigerant temperature detection unit 65 is equal to or lower than a predetermined first threshold. As a result, when the temperature of the second refrigerant detected by second refrigerant temperature detection unit 65 is equal to or lower than the predetermined first threshold, control unit 6 can switch from bypass flow path 33 to the flow path leading to steam generator 24 by second switching unit 30. Therefore, cooling operation can be started promptly after the temperature of the second refrigerant becomes equal to or lower than the predetermined first threshold.

[0123] The other effects of the third embodiment are the same as those of the second embodiment.

[0124] [Fourth embodiment] Next, a vending machine 200 including a cooling system 100 according to a fourth embodiment of the present invention will be described with reference to Figures 15 to 21. Unlike the first embodiment, the fourth embodiment describes an example in which the cooling system 100 is configured to include a first cycle connecting flow path 70 and a second cycle connecting flow path 73 that connect the refrigeration cycle 1 and the ejector cycle 2. Note that the same components as those in the first embodiment are designated by the same reference numerals, and their description will be omitted.

[0125] 15 is a graph showing the relationship between the saturation temperature Ts of the suction flow of the ejector 25 and the thermal COP of the ejector cycle 2 when the outside air temperature is 32°C and the refrigerant is R1336mzzE. The thermal COP in the ejector cycle means the value obtained by dividing the cooling capacity generated by the ejector suction flow by the heat input to the steam generation section. As shown in FIG. 15, at a high outside air temperature (32°C), the ejector cycle 2 cannot lower the evaporation temperature of the heat exchanger 3 to the evaporation temperature (saturation temperature Ts of the suction flow of the ejector 25: 5°C) required to maintain the temperature of the commodities stored in the storage compartment 4 of the vending machine 200.

[0126] 16 is a graph showing the relationship between the saturation temperature Td of the discharge flow of the ejector 25 and the thermal COP of the ejector cycle 2 when the saturation temperature Ts of the suction flow of the ejector 25 is 5°C when the refrigerant is R1336mzzE. As described above, in the ejector cycle 2, at a high outside air temperature (32°C), the evaporation temperature of the heat exchanger 3 cannot be lowered to the evaporation temperature (saturation temperature Ts of the suction flow of the ejector 25: 5°C) required to maintain the temperature of the commodities stored in the storage compartment 4 of the vending machine 200. However, as shown in FIG. 16, when the saturation temperature Td of the discharge flow of the ejector 25 is 27°C (≈ outside air temperature: 22°C) or lower, the saturation temperature of the suction flow of the ejector 25 can be set to 5°C. In other words, when the saturation temperature Td of the discharge flow of the ejector 25 is 27°C (≒outside air temperature: 22°C) or lower, it is possible to lower the refrigerant to the evaporation temperature (saturation temperature Ts of the suction flow of the ejector 25: 5°C) required to maintain the temperature of the commodities stored in the storage compartment 4 of the vending machine 200 by operating the ejector cycle 2 alone, without operating the refrigeration cycle 1 by driving the compressor 10.

[0127] Therefore, in this embodiment, the control unit 6, in a predetermined case, stops the compressor 10 and controls the refrigerant to flow between the second condenser 20 of the ejector cycle 2 and the evaporator 13 of the refrigeration cycle 1 through the first cycle connecting passage 70 and the second cycle connecting passage 73 without passing through the first condenser 14 and the heat exchanger 3. That is, in a predetermined case, the control unit 6 controls the operation of the ejector cycle 2 alone without operating the refrigeration cycle 1 by driving the compressor 10.

[0128] (Cooling system) As shown in FIG. 17, the cooling system 100 includes a first cycle connecting passage 70, a first on-off valve 71, a third on-off valve 72, a second cycle connecting passage 73, a second on-off valve 74, and a mixed refrigerant pressure detection unit 75.

[0129] The first-cycle connecting flow path 70 is a flow path that connects the refrigeration cycle 1 and the ejector cycle 2. The first-cycle connecting flow path 70 is branched from the flow path between the evaporator 13 and the compressor 10 in the refrigeration cycle 1, and is configured to merge with the flow path between the heat exchanger 3 and the suction port 25b of the ejector 25 in the ejector cycle 2.

[0130] The first on-off valve 71 is provided in the first cycle connecting flow path 70. The first on-off valve 71 is configured to fully open or fully close the first cycle connecting flow path 70 under the control of the control unit 6.

[0131] The third on-off valve 72 is provided in the refrigeration cycle 1 between the compressor 10 and a branching portion where the first cycle connecting flow path 70 branches off between the evaporator 13 and the compressor 10. The third on-off valve 72 is configured to fully open or fully close the flow path between the compressor 10 and the branching portion where the first cycle connecting flow path 70 branches off, under the control of the control unit 6.

[0132] The second-cycle connecting flow path 73 is a flow path that connects the refrigeration cycle 1 and the ejector cycle 2. The second-cycle connecting flow path 73 is configured to branch off from the flow path between the first branch portion 29 and the second expansion valve 22 in the ejector cycle 2 and merge into the flow path between the condenser 11 and the first expansion valve 12 in the refrigeration cycle 1. Specifically, the second-cycle connecting flow path 73 is a flow path that branches off from the flow path between the first branch portion 29 and the second expansion valve 22 in the ejector cycle 2 and merges into the flow path between the heat exchanger 3 and the first expansion valve 12 in the refrigeration cycle 1.

[0133] The second on-off valve 74 is provided in the second cycle connecting flow path 73. The second on-off valve 74 is configured to fully open or fully close the second cycle connecting flow path 73 under the control of the control unit 6.

[0134] The mixed refrigerant pressure detection unit 75 is configured to detect the pressure of the mixed refrigerant, which is a mixture of the first refrigerant and the second refrigerant, and is discharged from the discharge port 25c of the ejector 25. The mixed refrigerant pressure detection unit 75 is provided, for example, between the discharge port 25c of the ejector 25 and the second condenser 20 in the ejector cycle 2.

[0135] In this embodiment, the refrigeration cycle 1 and the ejector cycle 2 are connected via a first-cycle connecting passage 70 and a second-cycle connecting passage 73. The same type of refrigerant flows through the refrigeration cycle 1 and the ejector cycle 2. That is, in this embodiment, the first refrigerant and the second refrigerant are the same refrigerant, and the first refrigerant, the second refrigerant, and the mixed refrigerant are also the same refrigerant.

[0136] The third condenser 26 is provided in the heating flow path of the ejector cycle 2. In this embodiment, the heating flow path is a flow path that branches off from the first switching unit 28 and merges with a flow path between the discharge port 25c of the ejector 25 and the second condenser 20 via a third expansion valve 27. The third expansion valve 27 is provided in the heating flow path downstream of the third condenser 26. The third expansion valve 27 is configured to expand the mixed refrigerant.

[0137] The control unit 6 is configured to control the operation of the compressor 10 and the opening and closing of the first on-off valve 71, the second on-off valve 74, and the third on-off valve 72.

[0138] Specifically, during CCC operation, when the pressure value detected by the mixed refrigerant pressure detection unit 75 is equal to or lower than a predetermined second threshold value, the control unit 6 is configured to stop the compressor 10 and fully open the first on-off valve 71 and the second on-off valve 74 to control the mixed refrigerant to circulate to the second condenser 20 of the ejector cycle 2 and the evaporator 13 of the refrigeration cycle 1 via the first cycle connecting passage 70 and the second cycle connecting passage 73, without passing through the first condenser 14 and the heat exchanger 3.

[0139] In addition, during HCC operation, when the pressure value detected by the mixed refrigerant pressure detection unit 75 is equal to or lower than a predetermined second threshold value, the control unit 6 stops the compressor 10 and fully opens the first on-off valve 71 and the second on-off valve 74 to allow a portion of the mixed refrigerant flowing out from the steam generator 24 to flow through the first cycle connecting passage 70 and the second cycle connecting passage 73 to the second condenser 20 of the ejector cycle 2 and the evaporator 13 of the refrigeration cycle 1 without passing through the first condenser 14 and the heat exchanger 3, and is configured to control the remaining mixed refrigerant flowing out from the steam generator 24 to flow through the third condenser 26 without passing through the ejector 25 and the heat exchanger 3, and to flow into the passage between the discharge port 25c of the ejector 25 and the second condenser 20 via the third expansion valve 27.

[0140] In addition, in CCC operation and HCC operation, when the pressure value detected by the mixed refrigerant pressure detection unit 75 exceeds a predetermined second threshold, the control unit 6 is configured to operate the compressor 10 and fully close the first on-off valve 71 and the second on-off valve 74 to control the mixed refrigerant to circulate through each of the refrigeration cycle 1 and the ejector cycle 2.

[0141] (Control by the control unit for switching between combined operation of the refrigeration cycle and the ejector cycle and operation of the ejector cycle alone) <Combined operation of the refrigeration cycle and the ejector cycle in the CCC operation>[ As shown in FIG. 18, in the CCC operation, when the pressure value detected by the mixed refrigerant pressure detection unit 75 exceeds a predetermined second threshold value, the control unit 6 operates the compressor 10 and fully closes the first on - off valve 71 and the second on - off valve 74, and controls the mixed refrigerant to flow through each of the refrigeration cycle 1 and the ejector cycle 2. That is, the control unit 6 operates the refrigeration cycle 1 and the ejector cycle 2 in combination. The second threshold value is, for example, the pressure value of the discharge flow of the ejector 25 such that the saturation temperature of the discharge flow of the ejector 25 becomes 27°C.

[0142] In this case, the control unit 6 performs control to operate the compressor 10. As a result, the mixed refrigerant circulates in the refrigeration cycle 1. Further, the control unit 6 performs control to fully open the third on - off valve 72.

[0143] Using the ejector cycle 2, the cooling of the internal air of the first storage 41, the second storage 42, and the third storage 43 via the ejector 25 is assisted. By the first switching unit 28, all of the mixed refrigerant flowing out from the vapor generator 24 flows into the inlet 25a of the ejector 25.

[0144] In the refrigeration cycle 1, the mixed refrigerant flows from the compressor 10 through the first condenser 14, the heat exchanger 3, the first expansion valve 12, and the evaporators 13 of the first storage 41, the second storage 42, and the third storage 43 in this order, and returns to the compressor 10 through the third on - off valve 72.

[0145] Also, in the ejector cycle 2, all of the mixed refrigerant flowing out from the steam generator 24 flows into the inlet 25a of the ejector 25 through the first switching section 28, and from the outlet 25c of the ejector 25, it circulates through the second condenser 20 and the storage section 21 in this order. At the same time, a part of the mixed refrigerant flows through the second expansion valve 22 and the heat exchanger 3 in this order through the first branch section 29 and flows into the suction port 25b of the ejector 25, and the part other than a part of the mixed refrigerant flows through the liquid delivery pump 23, the steam generator 24, and the first switching section 28 in this order and flows into the inlet 25a of the ejector 25.

[0146] <Ejector cycle independent operation in CCC operation> As shown in FIG. 19, in the CCC operation, when the pressure value detected by the mixed refrigerant pressure detection section 75 is below a predetermined second threshold value, the control section 6 stops the compressor 10 and fully opens the first on-off valve 71 and the second on-off valve 74, and circulates the mixed refrigerant through the first cycle connection passage 70 and the second cycle connection passage 73 without passing through the first condenser 14 and the heat exchanger 3, and controls to circulate it to the second condenser 20 of the ejector cycle 2 and the evaporator 13 of the refrigeration cycle 1. That is, the control section 6 stops the operation of the refrigeration cycle 1 and operates the ejector cycle 2 independently.

[0147] In this case, the control section 6 performs control to stop the operation of the compressor 10. Thereby, the mixed refrigerant is not sent from the compressor 10 to the first condenser 14 and the heat exchanger 3. Further, the control section 6 performs control to fully close the third on-off valve 72. Further, the control section 6 performs control to fully close the second expansion valve 22.

[0148] By the independent operation of the ejector cycle 2, the cooling of the internal air of the first storage 41, the second storage 42, and the third storage 43 through the ejector 25 is performed. By the first switching section 28, all of the mixed refrigerant flowing out from the steam generator 24 flows into the inlet 25a of the ejector 25.

[0149] All of the mixed refrigerant flowing out of the steam generator 24 flows into the inlet 25a of the ejector 25 via the first switching unit 28, and from the outlet 25c of the ejector 25, it flows through the second condenser 20 and the storage unit 21 in this order. Through the first branch unit 29, a part of the mixed refrigerant flows through the second cycle connection channel 73, the second on-off valve 74, the first expansion valve 12, and the evaporators 13 of the first storage unit 41, the second storage unit 42, and the third storage unit 43 in this order, and also flows through the first cycle connection channel 70 and the first on-off valve 71, and then flows into the suction port 25b of the ejector 25. Further, through the first branch unit 29, the part other than a part of the mixed refrigerant flows through the liquid delivery pump 23, the steam generator 24, and the first switching unit 28 in this order and then flows into the inlet 25a of the ejector 25.

[0150] <Combined operation of refrigeration cycle and ejector cycle in HCC operation> As shown in FIG. 20, in the HCC operation, when the pressure value detected by the mixed refrigerant pressure detection unit 75 exceeds a predetermined second threshold value, the control unit 6 operates the compressor 10 and fully closes the first on-off valve 71 and the second on-off valve 74, and performs control to make the mixed refrigerant flow through each of the refrigeration cycle 1 and the ejector cycle 2. That is, the control unit 6 operates using the refrigeration cycle 1 and the ejector cycle 2 in combination.

[0151] In this case, the control unit 6 performs control to operate the compressor 10. Thereby, the mixed refrigerant circulates in the refrigeration cycle 1. Further, the control unit 6 performs control to fully close the first on-off valve 71 and the second on-off valve 74 and fully open the third on-off valve 72.

[0152] Using the ejector cycle 2, heating of the air inside the first storage unit 41 not passing through the ejector 25 and auxiliary cooling of the air inside the second storage unit 42 and the third storage unit 43 passing through the ejector 25 are performed in parallel. By the first switching unit 28, a part of the mixed refrigerant flowing out of the steam generator 24 flows into the inlet 25a of the ejector 25, and the part other than a part of the mixed refrigerant flowing out of the steam generator 24 flows into the third condenser 26.

[0153] In the refrigeration cycle 1, the mixed refrigerant flows from the compressor 10 through the first condenser 14, the heat exchanger 3, the first expansion valve 12, and the evaporators 13 of the second storage 42 and the third storage 43 in this order, and returns to the compressor 10 via the third on-off valve 72.

[0154] Also, in the ejector cycle 2, a part of the mixed refrigerant flowing out from the steam generator 24 flows into the inlet 25a of the ejector 25 through the first switching unit 28, and from the outlet 25c of the ejector 25, it flows through the second condenser 20 and the storage unit 21 in this order. At the same time, a part of the mixed refrigerant flows through the second expansion valve 22 and the heat exchanger 3 in this order through the first branch unit 29 and flows into the suction port 25b of the ejector 25. Also, other than a part of the second refrigerant, the rest flows through the liquid delivery pump 23, the steam generator 24, and the first switching unit 28 in this order through the first branch unit 29 and flows into the inlet 25a of the ejector 25. Further, other than a part of the mixed refrigerant flowing out from the steam generator 24, it flows through the third condenser 26 through the first switching unit 28 and flows into the flow path between the outlet 25c of the ejector 25 and the second condenser 20 via the third expansion valve 27.

[0155] <Single operation of the ejector cycle in HCC operation> As shown in FIG. 21, in the HCC operation, when the pressure value detected by the mixed refrigerant pressure detection unit 75 is below a predetermined second threshold value, the control unit 6 stops the compressor 10 and fully opens the first on-off valve 71 and the second on-off valve 74, and allows a part of the mixed refrigerant flowing out from the steam generator 24 to flow through the first cycle connection flow path 70 and the second cycle connection flow path 73 without passing through the first condenser 14 and the heat exchanger 3, and into the second condenser 20 of the ejector cycle ② and the evaporator 13 of the refrigeration cycle 1. Also, other than a part of the mixed refrigerant flowing out from the steam generator 24, it is made to flow through the third condenser 26 without flowing through the ejector 25 and the heat exchanger 3, and at the same time, control is performed to make it flow into the flow path between the outlet 25c of the ejector 25 and the second condenser 20. That is, the control unit 6 stops the operation of the refrigeration cycle 1 and operates the ejector cycle 2 alone.

[0156] In this case, the control unit 6 performs control to stop the operation of the compressor 10. As a result, the mixed refrigerant is not sent from the compressor 10 to the first condenser 14 and the heat exchanger 3. The control unit 6 also performs control to fully close the third on-off valve 72. The control unit 6 also performs control to fully close the second expansion valve 22.

[0157] By the sole operation of the ejector cycle 2, the air inside the first storage compartment 41 is heated without using the ejector 25, and the air inside the second storage compartment 42 and the third storage compartment 43 is cooled via the ejector 25. The first switching unit 28 causes a portion of the mixed refrigerant flowing out from the steam generator 24 to flow into the inlet 25a of the ejector 25, and causes the remaining portion of the mixed refrigerant flowing out from the steam generator 24 to flow into the third condenser 26.

[0158] A portion of the mixed refrigerant flowing out from the steam generator 24 flows into the inlet 25a of the ejector 25 via the first switching unit 28, and then flows from the discharge port 25c of the ejector 25 through the second condenser 20 and the storage unit 21 in this order. Via the first branching unit 29, a portion of the mixed refrigerant flows through the second cycle connecting flow path 73, the second on-off valve 74, the first expansion valve 12, and the evaporators 13 of the second storage chamber 42 and the third storage chamber 43 in this order, and also flows through the first cycle connecting flow path 70 and the first on-off valve 71, before flowing into the suction port 25b of the ejector 25. Furthermore, via the first branching unit 29, the rest of the mixed refrigerant flows through the liquid feed pump 23, the steam generator 24, and the first switching unit 28 in this order, before flowing into the inlet 25a of the ejector 25.

[0159] In addition, all but a portion of the mixed refrigerant flowing out from the steam generator 24 flows through the third condenser 26 via the first switching unit 28 and flows into the flow path between the discharge port 25c of the ejector 25 and the second condenser 20 via the third expansion valve 27.

[0160] The other configurations of the fourth embodiment are the same as those of the first embodiment.

[0161] (Effects of the fourth embodiment) In the fourth embodiment, the following effects can be obtained.

[0162] As described above, the fourth embodiment includes a first-cycle connecting flow path 70 that branches off from a flow path between the evaporator 13 and the compressor 10 in the refrigeration cycle 1 and joins a flow path between the heat exchanger 3 and the suction port 25 b of the ejector 25 in the ejector cycle 2, a first on-off valve 71 that is provided in the first-cycle connecting flow path 70 and fully opens or closes the first-cycle connecting flow path 70, a second-cycle connecting flow path 73 that branches off from a flow path between the first branch portion 29 and the second expansion valve 22 in the ejector cycle 2 and joins a flow path between the condenser 11 and the first expansion valve 12 in the refrigeration cycle 1, a second on-off valve 74 that is provided in the second-cycle connecting flow path 73 and fully opens or closes the second-cycle connecting flow path 73, and a mixed refrigerant pressure detection unit 75 that detects the pressure of a mixed refrigerant in which the first refrigerant and the second refrigerant are mixed and discharged from a discharge port 25 c of the ejector 25. and a control unit 6 that controls operation of the compressor 10 and opening and closing of the first on-off valve 71 and the second on-off valve 74. When the pressure value detected by the mixed refrigerant pressure detection unit 75 is equal to or lower than a predetermined second threshold, the control unit 6 stops the compressor 10 and fully opens the first on-off valve 71 and the second on-off valve 74 to cause the mixed refrigerant to flow through the first cycle connecting flow path 70 and the second cycle connecting flow path 73 to the second condenser 20 of the ejector cycle 2 and the evaporator 13 of the refrigeration cycle 1 without passing through the first condenser 14 and the heat exchanger 3. When the pressure value detected by the mixed refrigerant pressure detection unit 75 exceeds the predetermined second threshold, the control unit 6 operates the compressor 10 and fully closes the first on-off valve 71 and the second on-off valve 74 to cause the mixed refrigerant to flow through each of the refrigeration cycle 1 and the ejector cycle 2. As a result, when the pressure value of the mixed refrigerant discharged from the discharge port 25c of the ejector 25, which correlates with the outside air temperature and the saturation temperature of the discharge flow of the ejector 25, is equal to or lower than a predetermined second threshold value, the compressor 10 is stopped and the mixed refrigerant can be circulated to the second condenser 20 of the ejector cycle 2 and the evaporator 13 of the refrigeration cycle 1 via the first cycle connecting flow path 70 and the second cycle connecting flow path 73. Therefore, when cooling the object to be cooled, the energy saving performance of the cooling system 100 can be further improved by stopping the compressor 10.

[0163] Furthermore, in the fourth embodiment, as described above, the ejector cycle 2 includes the third condenser 26 that heats the heating target by condensing the mixed refrigerant flowing out from the steam generator 24, the third expansion valve 27 that is provided downstream of the third condenser 26 and expands the mixed refrigerant, and the first switching unit 28 that is provided between the steam generator 24 and the inlet 25 a of the ejector 25 and switches between a cooling operation in which all of the mixed refrigerant flowing out from the steam generator 24 flows into the ejector 25 and a cooling / heating operation in which a portion of the mixed refrigerant flowing out from the steam generator 24 flows into the ejector 25 and all but a portion of the mixed refrigerant flowing out from the steam generator 24 flows into the third condenser 26, and the control unit 6 stops the compressor 10 and controls the first on-off valve 71 and the first on-off valve 72 when the pressure value detected by the mixed refrigerant pressure detection unit 75 is equal to or lower than the predetermined second threshold during the cooling / heating operation switched from the cooling operation by the first switching unit 28. and the second on-off valve 74 are fully opened, so that a portion of the mixed refrigerant flowing out from the steam generator 24 is circulated to the second condenser 20 of the ejector cycle 2 and the evaporator 13 of the refrigeration cycle 1 via the first cycle connecting flow path 70 and the second cycle connecting flow path 73 without passing through the first condenser 14 and the heat exchanger 3, and the remaining portion of the mixed refrigerant flowing out from the steam generator 24 is circulated to the third condenser 26 without passing through the ejector 25 and the heat exchanger 3, and is caused to flow into the flow path between the discharge port 25c of the ejector 25 and the second condenser 20 via the third expansion valve 27. When the pressure value detected by the mixed refrigerant pressure detection unit 75 exceeds a predetermined second threshold, the compressor 10 is operated, and the first on-off valve 71 and the second on-off valve 74 are fully closed, so that the mixed refrigerant is circulated to each of the refrigeration cycle 1 and the ejector cycle 2 including the third condenser 26.As a result, when the pressure value of the mixed refrigerant discharged from the discharge port 25c of the ejector 25, which correlates with the outside air temperature and the saturation temperature of the discharge flow of the ejector 25, is equal to or lower than a predetermined second threshold value, the compressor 10 is stopped, and the mixed refrigerant is circulated to the second condenser 20 of the ejector cycle 2 and the evaporator 13 of the refrigeration cycle 1 via the first cycle connecting flow path 70 and the second cycle connecting flow path 73, and the mixed refrigerant is also circulated to the third condenser 26.Therefore, when cooling an object to be cooled and heating an object to be heated, the energy-saving performance of the cooling system 100 can be further improved by stopping the compressor 10.

[0164] The other effects of the fourth embodiment are the same as those of the first embodiment.

[0165] [Variations] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims rather than the above description of the embodiments, and further includes all modifications (variations) within the meaning and scope of the claims.

[0166] For example, in the first to fourth embodiments, the cooling system is provided in a vending machine, but the present invention is not limited to this. For example, the cooling system may be configured to be provided in a showcase or a freezer.

[0167] In addition, in the first to third embodiments, the first refrigerant and the second refrigerant are different types of refrigerants, but the present invention is not limited to this. For example, the first refrigerant and the second refrigerant may be the same refrigerant.

[0168] In addition, in the first to fourth embodiments, the heat exchanger in the condensing section is disposed downstream of the first condenser and upstream of the first expansion valve, but the present invention is not limited to this. For example, the heat exchanger in the condensing section may be configured to be disposed upstream of the first condenser.

[0169] In addition, in the first to fourth embodiments, an example was shown in which a heater for heating assistance was provided in the first storage compartment 41, but the present invention is not limited to this. For example, the first storage compartment 41 may be configured to be heated by a heat pump. [Explanation of symbols]

[0170] 1 Refrigeration cycle 2 Ejector cycle 3 Heat exchanger 4 Containment 6 Control Unit 10 Compressor 11 Condenser 12 First expansion valve 13 Evaporator 14 First condenser 20 Second condenser 21 Storage section 22 Second expansion valve 23 Liquid transfer pump 24 Steam Generator 25 Ejector 25a Inlet 25b Suction port 25c outlet 26 Third condenser 27 Third expansion valve 28 First switching section 29 First Branch 30 Second switching section 31 Second Branch 32 Third switching section 33 Bypass flow path 60 Inlet pressure detection unit 61 Suction port pressure detection unit 62 Outlet pressure detection unit 63 Cooling object temperature detection unit 64 Heating object temperature detection unit 65 Second refrigerant temperature detection unit 70 First cycle connecting flow path 71 First shut-off valve 73 Second cycle connecting flow path 74 Second shut-off valve 75 Mixed refrigerant pressure detection unit 100 Cooling System 200 vending machines

Claims

1. The refrigeration cycle and The ejector cycle, a heat exchanger provided across the refrigeration cycle and the ejector cycle, The refrigeration cycle includes: a compressor that compresses a first refrigerant; a condensing unit connected in series downstream of the compressor, the condensing unit including: a first condenser configured to condense the first refrigerant; and the heat exchanger configured to condense the first refrigerant by exchanging heat between the first refrigerant and a second refrigerant circulating through the ejector cycle. a first expansion valve that expands the first refrigerant flowing out from the condenser; an evaporator that cools an object to be cooled by evaporating the first refrigerant expanded by the first expansion valve, The ejector cycle includes: a second condenser that condenses the second refrigerant; a first branch portion provided in a flow path downstream of the second condenser; a second expansion valve that expands a portion of the second refrigerant that flows out of the second condenser and into the second refrigerant via the first branch portion; the heat exchanger that evaporates the second refrigerant by exchanging heat between the second refrigerant expanded by the second expansion valve and the first refrigerant; a liquid feed pump that feeds all but a portion of the second refrigerant that flows out of the second condenser and into the second refrigerant via the first branch portion; a vapor generator that evaporates the second refrigerant delivered from the liquid delivery pump by an external heat source; an ejector that introduces the second refrigerant evaporated in the vapor generator as a driving flow from an inlet, thereby introducing the second refrigerant flowing out of the heat exchanger as a suction flow from a suction port, and discharges the second refrigerant, a mixture of the driving flow and the suction flow, from a discharge port, thereby sending the second refrigerant to the second condenser.

2. The cooling system according to claim 1 , wherein in the condenser section, the heat exchanger is disposed downstream of the first condenser and upstream of the first expansion valve.

3. The ejector cycle includes: a third condenser that heats a heating target by condensing the second refrigerant flowing out from the steam generator; a third expansion valve provided downstream of the third condenser and configured to expand the second refrigerant; a first switching unit that is provided between the steam generator and the inlet of the ejector and that switches between a cooling operation in which all of the second refrigerant that has flowed out from the steam generator flows into the ejector and a cooling / heating operation in which a portion of the second refrigerant that has flowed out from the steam generator flows into the ejector and all but a portion of the second refrigerant that has flowed out from the steam generator flows into the third condenser, 2. The cooling system of claim 1, wherein during the cooling and heating operation, all but a portion of the second refrigerant flowing out of the first switching unit flows through the third condenser without flowing through the ejector and the heat exchanger, and flows into a flow path between the discharge port of the ejector and the second condenser via the third expansion valve.

4. The cooling system according to claim 1 , wherein the second refrigerant is a low-pressure refrigerant having a higher normal boiling point, which is a boiling point at 1 atmospheric pressure, than the first refrigerant.

5. The ejector cycle includes: a third condenser that heats a heating target by condensing the second refrigerant flowing out from the steam generator; a second switching unit that is provided between the steam generator and the inlet of the ejector and that switches between a cooling operation in which all of the second refrigerant that has flowed out from the steam generator flows into the inlet of the ejector and a heating operation in which all of the second refrigerant that has flowed out from the steam generator flows into the third condenser without flowing into the inlet of the ejector, a control unit that controls switching between the cooling operation and the heating operation by the second switching unit, 2. The cooling system of claim 1, wherein, in the heating operation switched from the cooling operation by the second switching unit, the control unit controls the second refrigerant flowing out of the second switching unit to flow through the third condenser without flowing through the ejector and the heat exchanger, and controls the second refrigerant flowing out of the third condenser to flow into a flow path between the second condenser and the first branch unit.

6. The cooling apparatus further includes a cooling object temperature detection unit that detects the temperature of the cooling object, and a heating object temperature detection unit that detects the temperature of the heating object, 6. The cooling system according to claim 5, wherein the control unit controls the second switching unit to switch between the cooling operation and the heating operation based on the temperature of the cooling object detected by the cooling object temperature detection unit and the temperature of the heating object detected by the heating object temperature detection unit.

7. The ejector cycle includes: a reservoir provided downstream of the second condenser and upstream of the first branch portion, the reservoir configured to retain the second refrigerant condensed by the second condenser; a second branch portion provided in a flow path between the liquid feed pump and the steam generator; a bypass flow path branched from the second branch portion and joining a joining portion provided in a flow path between the discharge port of the ejector and the second condenser; a third switching unit provided in the second branch portion and configured to switch between the flow path leading to the steam generator and the bypass flow path, 6. The cooling system according to claim 5, wherein the control unit controls the second refrigerant to circulate between the second condenser, the storage unit, and the liquid feed pump via the bypass flow path by switching from the heating operation to the cooling operation using the second switching unit and switching from the flow path leading to the steam generator to the bypass flow path using the third switching unit.

8. a second refrigerant temperature detection unit that detects a temperature of any one of the second refrigerant flowing out from the second condenser, the second refrigerant stored in the storage unit, and the second refrigerant flowing into the liquid feed pump, 8. The cooling system according to claim 7, wherein the control unit controls the third switching unit to switch from the flow path leading to the steam generator to the bypass flow path, and then controls the second switching unit to switch from the bypass flow path to the flow path leading to the steam generator when the temperature of the second refrigerant detected by the second refrigerant temperature detection unit is equal to or lower than a predetermined first threshold.

9. a first cycle connecting flow path branching from a flow path between the evaporator and the compressor in the refrigeration cycle and joining a flow path between the heat exchanger and the suction port of the ejector in the ejector cycle; a first on-off valve provided in the first cycle connecting passage and configured to fully open or fully close the first cycle connecting passage; a second-cycle connecting passage branching from a passage between the first branch portion and the second expansion valve in the ejector cycle and joining a passage between the condenser portion and the first expansion valve in the refrigeration cycle; a second on-off valve provided in the second cycle connecting passage and configured to fully open or fully close the second cycle connecting passage; a mixed refrigerant pressure detection unit that detects the pressure of a mixed refrigerant in which the first refrigerant and the second refrigerant are mixed and discharged from the discharge port of the ejector; a control unit that controls operation of the compressor, and opening and closing of the first on-off valve and the second on-off valve, The control unit when the pressure value detected by the mixed refrigerant pressure detection unit is equal to or lower than a predetermined second threshold value, the compressor is stopped, and the first on-off valve and the second on-off valve are fully opened to cause the mixed refrigerant to flow through the second condenser of the ejector cycle and the evaporator of the refrigeration cycle via the first cycle connecting flow path and the second cycle connecting flow path without passing through the first condenser and the heat exchanger, 2. The cooling system according to claim 1, wherein, when the pressure value detected by the mixed refrigerant pressure detection unit exceeds the predetermined second threshold, the compressor is operated, and the first on-off valve and the second on-off valve are fully closed to cause the mixed refrigerant to circulate through each of the refrigeration cycle and the ejector cycle.

10. The ejector cycle includes: a third condenser that condenses the mixed refrigerant flowing out from the steam generator to heat a heating target; a third expansion valve provided downstream of the third condenser to expand the mixed refrigerant; a first switching unit that is provided between the steam generator and the inlet of the ejector and that switches between a cooling operation in which all of the mixed refrigerant that has flowed out from the steam generator flows into the ejector and a cooling / heating operation in which a portion of the mixed refrigerant that has flowed out from the steam generator flows into the ejector and all of the mixed refrigerant that has flowed out from the steam generator except for the portion flows into the third condenser, The control unit, in the cooling and heating operation switched from the cooling operation by the first switching unit, when the pressure value detected by the mixed refrigerant pressure detection unit is equal to or lower than the predetermined second threshold value, the compressor is stopped, and the first on-off valve and the second on-off valve are fully opened, so that a portion of the mixed refrigerant flowing out of the steam generator is circulated to the second condenser of the ejector cycle and the evaporator of the refrigeration cycle via the first cycle connecting flow path and the second cycle connecting flow path without passing through the first condenser and the heat exchanger, and the remaining portion of the mixed refrigerant flowing out of the steam generator is circulated to the third condenser without passing through the ejector and the heat exchanger, and is allowed to flow into a flow path between the discharge port of the ejector and the second condenser via the third expansion valve, 10. The cooling system according to claim 9, wherein, when the pressure value detected by the mixed refrigerant pressure detection unit exceeds the predetermined second threshold, the compressor is operated, and the first on-off valve and the second on-off valve are fully closed to cause the mixed refrigerant to circulate through each of the refrigeration cycle and the ejector cycle including the third condenser.

11. 2. The cooling system according to claim 1, further comprising a control unit that controls an opening degree of the second expansion valve and controls an amount of the second refrigerant delivered by the liquid delivery pump, based on a relationship between a pressure of the second refrigerant discharged from the discharge port of the ejector, a pressure of the second refrigerant introduced into the suction port of the ejector, and a pressure of the second refrigerant introduced into the inlet of the ejector.

12. The refrigeration cycle and The ejector cycle, a heat exchanger provided across the refrigeration cycle and the ejector cycle; a storage facility for storing merchandise; The refrigeration cycle includes: a compressor that compresses a first refrigerant; a condensing unit connected in series downstream of the compressor, the condensing unit including: a first condenser configured to condense the first refrigerant; and a heat exchanger configured to cool the first refrigerant by exchanging heat between the first refrigerant and a second refrigerant circulating through the ejector cycle. a first expansion valve that expands the first refrigerant flowing out from the condenser; an evaporator that cools the air in the storage compartment by evaporating the first refrigerant expanded by the first expansion valve, The ejector cycle includes: a second condenser that condenses the second refrigerant; a first branch portion provided downstream of the second condenser; a second expansion valve that expands a portion of the second refrigerant that flows out of the second condenser and into the second refrigerant via the first branch portion; the heat exchanger that evaporates the second refrigerant by exchanging heat between the second refrigerant expanded by the second expansion valve and the first refrigerant; a liquid feed pump that feeds all but the portion of the second refrigerant that flows out of the second condenser and into the second refrigerant via the first branch portion; a vapor generator that evaporates the second refrigerant delivered from the liquid delivery pump by an external heat source; an ejector that introduces the second refrigerant evaporated in the steam generator as a driving flow from an inlet, thereby introducing the second refrigerant flowing out of the heat exchanger as a suction flow from a suction port, and discharges the second refrigerant, a mixture of the driving flow and the suction flow, from a discharge port, thereby sending the second refrigerant to the second condenser.

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