JP2013152031A - Refrigerating apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refrigerating apparatus that can improve energy saving performance while suppressing costs low.SOLUTION: A refrigerating apparatus 1 includes a liquid tank 2 for storing heating medium liquid, a refrigerant circulation flow path (refrigerant pipe 3e) through which a refrigerant circulates, a freezer 3 for cooling the heating medium liquid in the liquid tank 2 by heat exchange between the heating medium liquid in the liquid tank 2 and the refrigerant flowing through the refrigerant circulation flow path, a refrigerant flow path (refrigerant pipe 4e) through which a refrigerant circulates, and a plurality of freezers 4 for supercooling the refrigerant flowing through the refrigerant circulation flow path by heat exchange between the heating medium liquid in the liquid tank 2 and the refrigerant flowing through the refrigerant circulation flow path. Thus, energy saving performance is improved while costs are suppressed low.

Description

  The present invention relates to a refrigeration apparatus, for example, a refrigeration apparatus that cools products in various stores.

  In various stores such as supermarkets and convenience stores, refrigerators that cool showcases, refrigerators, and the like are used for displaying refrigerated foods, frozen foods, and fresh foods. This refrigerator usually includes a compressor, a condenser, a liquid receiver, and the like, sends a refrigerant to an evaporator of a showcase or a refrigerator, and cools various products by heat exchange.

  In such a refrigerator, energy saving is desired. For example, a technology has been developed that realizes energy saving by improving the refrigeration capacity of a refrigerator by supercooling a liquid refrigerant. As this technique, an ice heat storage system, a supercooling system, etc. are proposed (for example, refer patent document 1 or patent document 2).

  In an ice heat storage system, brine (antifreeze) is cooled at night by the surplus capacity of the refrigerator, ice is made with the brine, then the brine is cooled with ice during the day, and the liquid refrigerant is cooled with the brine. In the supercooling system, the liquid refrigerant of the low-temperature refrigerator is directly supercooled by an efficient small-sized medium-temperature refrigerator. In addition, it is common to introduce either an ice heat storage system or a supercooling system in a store that aims to reduce running costs in addition to energy saving.

JP-A-10-122608 Japanese Patent Laid-Open No. 2008-82674

  However, in the ice heat storage system, if a system that covers the entire store is constructed, the initial cost (equipment cost + construction cost) becomes high. In large stores, the above-described indirect cooling type ice heat storage system using brine is often used, but in this case, a large circulation pump is essential, and the initial cost is also increased. In addition, the heat exchange loss is increased as compared with the direct cooling type ice heat storage system.

  On the other hand, in the supercooling system that directly supercools the liquid refrigerant, the total value of the legal refrigeration tons of two refrigerators (a small-sized medium temperature refrigerator dedicated to supercooling and a low-temperature refrigerator targeted for supercooling) is less than 20 tons (for example, The refrigerator is selected such that the refrigerant is chlorofluorocarbon. This is because a procedure based on the high-pressure gas method is required when the combined value of legal refrigeration tons of two refrigerators (common refrigerant) is 20 tons or more. When such a refrigerator is selected, the horsepower of the refrigerator that performs supercooling is limited, so that the energy saving performance is reduced.

  This invention is made | formed in view of the above, The objective is to provide the freezing apparatus which can improve energy saving performance, suppressing cost.

  The refrigeration apparatus according to the present invention has a liquid tank for storing the heat medium liquid and a refrigerant circulation channel through which the refrigerant circulates, and heat exchange between the heat medium liquid in the liquid tank and the refrigerant flowing through the refrigerant circulation channel. , A refrigerator that cools the heat medium liquid in the liquid tank, and a refrigerant circulation channel through which the refrigerant circulates, and the refrigerant is obtained by heat exchange between the heat medium liquid in the liquid tank and the refrigerant that flows through the refrigerant circulation channel. And a plurality of refrigerators for supercooling the refrigerant flowing through the circulation flow path.

  In the refrigeration apparatus according to the present invention, the refrigerator that cools the heat medium liquid preferably changes the temperature of the refrigerant that exchanges heat with the heat medium liquid in the liquid tank according to the season.

  Further, in the above-described refrigeration apparatus according to the present invention, the refrigerator that includes the temperature detector that detects the temperature of the heat medium liquid in the liquid tank and that supercools the refrigerant is provided in the liquid tank detected by the temperature detector. It is desirable to limit the supercooling of the refrigerant according to the temperature of the heat medium liquid.

  In the refrigeration apparatus according to the present invention described above, the refrigerator that cools the heat medium liquid has a compressor, and it is desirable that the compressor be inverter-controlled.

  Further, in the above-described refrigeration apparatus according to the present invention, the refrigerator that cools the heat medium liquid is a small medium temperature refrigerator that refrigerates smaller than a refrigerator that has a horsepower that supercools the refrigerant, and the refrigerator that supercools the refrigerant is A low-temperature refrigerator that performs freezing is desirable.

  In the refrigeration apparatus according to the present invention described above, the liquid tank has a liquid chamber for storing the heat medium liquid for each refrigerator that supercools the refrigerant, and the refrigerator that cools the heat medium liquid is liquid Each chamber has a heat exchanger that performs heat exchange between the heat medium liquid in the liquid chamber and the refrigerant flowing in the refrigerant circulation flow path, and the refrigerator that supercools the refrigerant includes the heat medium liquid and the refrigerant in the liquid chamber. It is desirable to have a heat exchanger that performs heat exchange with the refrigerant flowing through the circulation channel.

  In the refrigeration apparatus according to the present invention described above, the refrigerator that cools the heat medium liquid adjusts the temperature of the heat medium liquid in the liquid chamber for each liquid chamber according to the cooling load of each refrigerator that supercools the refrigerant. It is desirable to do.

  According to the refrigeration apparatus of the present invention, the heat medium liquid in the liquid tank is cooled by one refrigerator, and the refrigerant of each refrigerator is supercooled by the heat medium liquid in the liquid tank. That is, the refrigerant of each refrigerator can be supercooled by the single refrigerator via the heat medium liquid in the liquid tank. This eliminates the need for a circulation pump, which is essential in an indirect cooling type ice heat storage system, and further increases the horsepower of the refrigerator that cools the heat medium liquid compared to a supercooling system that directly supercools the liquid refrigerant. . As a result, the energy saving performance can be improved while suppressing the cost.

  In addition, when the refrigerator that cools the heat medium liquid changes the temperature of the refrigerant that exchanges heat with the heat medium liquid in the liquid tank according to the season, for example, if the season is summer, the season is spring or autumn. The temperature of the refrigerant is lowered compared to the case where the temperature is low, and if the season is winter, the temperature of the refrigerant is increased compared to the case where the season is spring or autumn. Thus, by changing the temperature of the refrigerant according to the season, that is, the temperature at which the heat medium liquid in the liquid tank is cooled, the temperature of the refrigerant when the season is summer is changed compared to the case where the temperature of the refrigerant is used over the four seasons. Since it becomes possible to suppress the power consumption of the refrigerator which cools, energy saving performance can be improved more.

  Further, when the refrigerator that supercools the refrigerant limits the supercooling of the refrigerant according to the temperature of the heat medium liquid in the liquid tank detected by the temperature detector, for example, the heat medium liquid in the liquid tank When the temperature of the refrigerant is higher than the set temperature, the supercooling of the refrigerant is stopped. On the other hand, when the temperature of the heat medium liquid in the liquid tank is equal to or lower than the set temperature, the refrigerant is supercooled. In this way, by restricting the supercooling of the refrigerant according to the temperature of the heat medium liquid in the liquid tank, reliable supercooling can be achieved, so that the energy saving performance can be improved with certainty.

  Moreover, since the refrigerator which cools a heat-medium liquid has a compressor, when performing inverter control of the compressor, since the frequency | count of a start / stop of a compressor decreases, energy saving performance can be improved more.

  In addition, when the refrigerator that cools the heat medium liquid is a small-sized medium-temperature refrigerator that performs refrigeration, it is possible to reduce the power consumption of the refrigerator as compared with the case of using a large-sized medium-temperature or small-sized low-temperature refrigerator. Therefore, energy saving performance can be further improved.

  Further, the liquid tank has a liquid chamber for storing the heat medium liquid for each refrigerator that supercools the refrigerant, and the refrigerator that cools the heat medium liquid has a heat medium liquid in the liquid chamber for each liquid chamber. And a refrigerant that flows through the refrigerant circulation channel, the refrigerant can be supercooled for each refrigerator, so that the refrigerant in each refrigerator can be reliably Can be supercooled. As a result, energy saving performance can be improved with certainty.

  Also, when the refrigerator that cools the heat medium liquid adjusts the temperature of the heat medium liquid in the liquid chamber for each liquid chamber according to the cooling load of each refrigerator that supercools the refrigerant, Even when each refrigerator to be cooled is a refrigerator having a different cooling temperature, such as refrigerated food, frozen food, and fresh food, the temperature of the heat transfer medium liquid is adjusted according to the cooling load, so that the refrigerant of each refrigerator As a result, it is possible to reliably cool the battery, so that the energy saving performance can be improved.

It is a figure which shows schematic structure of the freezing apparatus which concerns on the 1st Embodiment of this invention. It is a flowchart which shows the flow of the cooling process which the refrigeration apparatus shown in FIG. 1 performs. It is a figure which shows schematic structure of the freezing apparatus which concerns on the 2nd Embodiment of this invention. It is a flowchart which shows the flow of the cooling process which the refrigeration apparatus shown in FIG. 3 performs.

(First embodiment)
A first embodiment of the present invention will be described with reference to FIGS.

  As shown in FIG. 1, the refrigeration apparatus 1 according to the first embodiment of the present invention is configured to exchange heat between a liquid tank 2 that stores a heat medium liquid and a refrigerant that circulates in the heat medium liquid in the liquid tank 2. The three refrigerations of the B system, the C system, and the D system that supercool the refrigerant by heat exchange between the A medium refrigerator 3 that cools the heat medium liquid and the heat medium liquid in the liquid tank 2 and the circulating refrigerant. The machine 4 and the control part 5 which performs various controls are provided.

  The liquid tank 2 is a tank for storing a heat medium liquid (for example, a liquid such as brine (antifreeze) or water). Inside the liquid tank 2, a temperature detector 2 a that detects the temperature of the heat medium liquid stored in the liquid tank 2 is provided. The temperature detector 2 a is in the heat medium liquid and is provided on the inner wall of the liquid tank 2, and is electrically connected to the control unit 5. The temperature detector 2 a detects the temperature of the heat medium liquid in the liquid tank 2 and inputs it to the control unit 5. Various temperature sensors can be used as the temperature detector 2a.

  The A-system refrigerator 3 includes a compressor 3a that compresses the refrigerant, a condenser 3b that condenses the compressed refrigerant, an expansion valve 3c that depressurizes the refrigerant, a reduced-pressure refrigerant, and a heat medium in the liquid tank 2 It has a heat exchanger 3d that performs heat exchange with the liquid, and a refrigerant pipe 3e that connects these components. As this refrigerator 3, for example, a small-sized medium temperature refrigerator that performs refrigeration can be used.

  The refrigerant pipe 3e is a refrigerant circulation passage that connects the compressor 3a, the condenser 3b, the expansion valve 3c, and the heat exchanger 3d to circulate the refrigerant, and is constituted by a pipe such as a copper pipe, for example. The refrigerant flowing through the refrigerant pipe 3e circulates through the refrigerant pipe 3e while repeating the four steps of compression, condensation, expansion and evaporation.

  More specifically, the high-temperature and high-pressure gas refrigerant compressed by the compressor 3a flows into the condenser 3b, is cooled by the condenser 3b, and liquefies by releasing the condensation heat. Thereafter, through a liquid receiver (not shown), the normal-temperature and high-pressure liquid refrigerant flows into the expansion valve 3c, and is reduced in pressure by the expansion valve 3c so that the boiling point is lowered. The low-temperature and low-pressure liquid refrigerant in this state is heat-exchanged with the heat medium liquid in the liquid tank 2 by the heat exchanger 3d to boil and evaporate, and removes the surrounding heat to cool the heat medium liquid. Thereafter, the evaporated low-pressure gas refrigerant flows into the compressor 3a, and is compressed by the compressor 3a to become a high-temperature and high-pressure gas refrigerant. In order to liquefy it, cooling with air (air cooling) or cooling with water (water cooling) Again flows into the condenser 3b.

  An opening / closing valve 11 is provided in the refrigerant pipe 3e. The on-off valve 11 is positioned between the condenser 3b and the expansion valve 3c. As the on-off valve 11, for example, an electromagnetic valve or the like can be used. The on-off valve 11 is electrically connected to the control unit 5, and its driving is controlled by the control unit 5.

  Each of the refrigerators 4 of the B system, the C system, and the D system includes a compressor 4 a that compresses the refrigerant, a condenser 4 b that condenses the compressed refrigerant, and the refrigerant and the heat medium liquid in the liquid tank 2. It has a heat exchanger 4c that performs heat exchange, a cooler 4d that cools by depressurization and evaporation of the refrigerant, and a refrigerant pipe 4e that connects these parts. As each refrigerator 4, it is possible to use the low-temperature refrigerator which performs freezing, for example.

  The cooler 4d includes an expansion valve that decompresses the refrigerant and an evaporator that evaporates the decompressed refrigerant. The cooler 4d is built in, for example, a showcase or a refrigerator installed in various stores.

  The refrigerant pipe 4e is a refrigerant circulation passage that connects the compressor 4a, the condenser 4b, the heat exchanger 4c, and the cooler 4d to circulate the refrigerant, and is constituted by a pipe such as a copper pipe, for example. A bypass pipe 4f is connected to the refrigerant pipe 4e as a bypass of the refrigerant circulation passage. The bypass pipe 4f is provided in parallel with the heat exchanger 4c.

  The refrigerant pipe 4e is provided with an on-off valve 12, and the bypass pipe 4f is provided with an on-off valve 13. The on-off valve 12 is provided between the branch point of the refrigerant pipe 4e and the bypass pipe 4f and the heat exchanger 4c. The on-off valve 13 is provided at the branch point of the refrigerant pipe 4e and the bypass pipe 4f and their junction, that is, in the middle of the bypass pipe 4f. As the on-off valves 12 and 13, for example, electromagnetic valves can be used. These on-off valves 12 and 13 are electrically connected to the control unit 5, and their driving is controlled by the control unit 5.

  Here, the refrigerant flowing through the refrigerant pipe 4e circulates through the refrigerant pipe 4e while repeating four steps of compression, condensation, expansion, and evaporation. However, when the on-off valve 12 is in an open state and the on-off valve 13 is in a closed state, the refrigerant flows into the heat exchanger 4c, so that the heat exchanger 4c performs supercooling. On the other hand, when the on-off valve 12 is in the closed state and the on-off valve 13 is in the open state, the refrigerant does not flow to the heat exchanger 4c and supercooling is not performed. The supercooling refers to cooling the liquid refrigerant before entering the expansion valve in the cooler 4d and increasing the refrigerating capacity of the refrigerator 4.

  More specifically, when supercooling is performed, the high-temperature and high-pressure gas refrigerant compressed by the compressor 4a flows into the condenser 4b, is cooled by the condenser 4b, and releases the condensation heat to be liquefied. The room-temperature and high-pressure liquid refrigerant passes through the heat exchanger 4c. At this time, heat exchange between the liquid refrigerant and the heat medium liquid in the liquid tank 2 is performed, and the liquid refrigerant is cooled. Thereafter, the cooled liquid refrigerant flows into the cooler 4d, and is reduced in pressure by an expansion valve in the cooler 4d so that the boiling point is lowered. The low-temperature and low-pressure liquid refrigerant in this state is boiled and evaporated by the evaporator in the cooler 4d, and cools by taking away the surrounding heat. The evaporated low-pressure gas refrigerant flows into the compressor 4a, is compressed by the compressor 4a, becomes a high-temperature high-pressure gas refrigerant that can be liquefied by room temperature air, and flows into the condenser 4b again.

  On the other hand, when supercooling is not performed, heat exchange by the heat exchanger 4c described above is not performed, and the refrigerant flows directly from the condenser 4b into the expansion valve in the cooler 4d. As the multiple systems through which the refrigerant circulates, the B system, the C system, and the D system are provided as three systems. However, the present invention is not limited to this, and as long as at least two systems are provided. good.

  The control unit 5 includes a microcomputer that centrally controls each unit, a storage unit that stores various types of information and various programs, and an operation unit that receives input operations from an operator. As the storage unit, a memory, a hard disk drive (HDD), or the like can be used. The controller 5 controls the on-off valves 11, 12 and 13 according to the temperature of the heat medium liquid in the liquid tank 2 detected by the temperature detector 2a (details will be described later).

  Next, the cooling process performed by the refrigeration apparatus 1 will be described. In addition, the control part 5 of the freezing apparatus 1 performs a cooling process based on various programs and various information.

  As shown in FIG. 2, first, the temperature of the refrigerant that cools the heat medium liquid in the liquid tank 2 is set according to the season (step S1). For example, when the season is summer, the refrigerant temperature is set lower than when the season is spring or autumn. Also, when the season is winter, the refrigerant temperature is set higher than when the season is spring or autumn. Thus, by changing the refrigerant temperature according to the season, it is possible to suppress the power consumption of the A-system refrigerator 3 as compared with the case where the refrigerant temperature in the summer season is used over the four seasons.

  Next, after the process of step S1, it is determined whether or not the temperature of the heat medium liquid in the liquid tank 2 is higher than a set temperature (step S2). The temperature of the heat medium liquid in the liquid tank 2 is always detected by the temperature detector 2 a and is input to the control unit 5. Moreover, preset temperature is determined so that it may become lower than the temperature of each refrigerant | coolant of B system, C system, and D system. Thereby, the supercooling with respect to each refrigerant | coolant of B system | strain, C system | strain, and D system | strain is attained.

  If it is determined in step S2 that the temperature of the heat medium liquid in the liquid tank 2 is higher than the set temperature (YES in step S2), the on-off valves 12 of the B system, the C system, and the D system are closed, The valve 13 is opened (step S3). Further, the A system on-off valve 11 is opened (step S4), and then the process is repeated from step S2.

  Thereby, in the B system, the C system, and the D system, the refrigerant flowing through the refrigerant pipe 4e is directly supplied to the cooler 4d without passing through the heat exchanger 4c (without performing supercooling). In system A, heat exchange between the refrigerant flowing in the refrigerant pipe 3e and the heat medium liquid in the liquid tank 2 is performed by the heat exchanger 3d in the liquid tank 2, and the heat medium liquid in the liquid tank 2 has its temperature Is cooled until the temperature reaches the set temperature (heat medium liquid cooling).

  On the other hand, in step S2, if it is determined that the temperature of the heat medium liquid in the liquid tank 2 is not higher than the set temperature, that is, not more than the set temperature (NO in step S2), the B system, the C system, and the D system Each on-off valve 13 is closed and each on-off valve 12 is opened (step S5). Further, the A system on-off valve 11 is closed (step S6), and then the process is repeated from step S2.

  Thereby, in B system, C system, and D system, the refrigerant which flows through refrigerant piping 4e is supercooled by heat exchanger 4c in liquid tank 2, and is supplied to cooler 4d (supercooling execution). By supercooling this refrigerant, it is possible to improve the refrigeration capacity of each refrigerator 4 and realize energy saving. Further, in the A system, the refrigerant stops flowing through the refrigerant pipe 3e, heat exchange between the refrigerant in the refrigerant pipe 3e and the heat medium liquid in the liquid tank 2 is not performed, and the heat medium liquid in the liquid tank 2 is cooled. Eliminate (without heating medium cooling).

  Thus, in the B system, the C system, and the D system, the refrigeration capacity of the refrigerator 4 is increased by supercooling. Thereby, it is possible to reduce the horsepower of the refrigerator 4 for energy saving, and it is also possible to reduce the refrigerant charging amount. Further, by performing the supercooling operation, it is possible to reduce the amount of power used at the peak time, and as a result, the basic charge can be reduced. In addition, power leveling can be achieved by using nighttime power with respect to the A-system refrigerator 3.

  It should be noted that the timing of closing the A system on-off valve 11 in step S6 described above is not immediately after each on-off valve 12 is opened in step S5, but a time difference is provided, and each control operation is performed after a certain time has elapsed. It is stable and suitable. That is, when the subcooling of the B system, the C system, and the D system starts, the temperature of the heat medium liquid in the liquid tank 2 gradually rises. Therefore, by providing the above time difference, YES / NO in step S2 It is possible to prevent the judgment from being switched rapidly, and to prevent the start and stop of the refrigerator 3 and the on / off of the on-off valves 11 and 12 from becoming complicated.

  As described above, according to the first embodiment, the heat medium liquid in the liquid tank 2 is cooled by the A system refrigerator 3, and the B medium, the C system, and the heat medium liquid in the liquid tank 2 are used. Each refrigerant of system D is supercooled. That is, the refrigerant of each system of the B system, the C system, and the D system can be supercooled by the A system refrigerator 3 through the heat medium liquid in the liquid tank 2. This eliminates the need for a circulation pump, which is essential in an indirect cooling type ice heat storage system, and further increases the horsepower of the A-system refrigerator 3 as compared with a supercooling system that directly supercools liquid refrigerant. As a result, the energy saving performance can be improved while suppressing the cost.

  In addition, since the A system refrigerator 3 changes the temperature of the refrigerant that exchanges heat with the heat medium liquid in the liquid tank 2 according to the season, for example, if the season is summer, the season is spring or autumn. Compared to a certain case, the temperature of the refrigerant is lowered, and when the season is winter, the temperature of the refrigerant is raised compared to the case where the season is spring or autumn. Thus, by changing the temperature of the refrigerant according to the season, that is, the temperature at which the heat medium liquid in the liquid tank 2 is cooled, compared to the case where the temperature of the refrigerant when the season is summer is used over the four seasons, Since the power consumption of the refrigerator 3 can be suppressed, the energy saving performance can be further improved.

  Further, in each of the refrigerators 4 of the B system, the C system, and the D system, the supercooling of the refrigerant is limited according to the temperature of the heat medium liquid in the liquid tank 2 by switching the open / close state of the open / close valves 12 and 13. For this reason, for example, when the temperature of the heat medium liquid in the liquid tank 2 is higher than the set temperature, the refrigerant cannot be supercooled, so the refrigerant supercooling is stopped. On the other hand, when the temperature of the heat medium liquid in the liquid tank 2 is equal to or lower than the set temperature, the refrigerant is supercooled. In this way, by restricting the supercooling of the refrigerant in accordance with the temperature of the heat medium liquid in the liquid tank 2, it is possible to perform reliable supercooling, and thus energy saving performance can be improved with certainty.

  Further, by controlling the compressor 3a of the A-system refrigerator 3 with an inverter, the number of start / stop times of the compressor 3a is reduced, so that the energy saving performance can be further improved.

  In addition, by using a small-sized medium temperature refrigerator that has a smaller horsepower than other refrigerators 4 as the A-system refrigerator 3, the large-scale medium-temperature and small-sized low-temperature refrigerators are used. Since power consumption can be suppressed, energy saving performance can be further improved.

(Second Embodiment)
A second embodiment of the present invention will be described with reference to FIGS.

  The second embodiment of the present invention is basically the same as the first embodiment. In the second embodiment, differences from the first embodiment will be described, the same parts as those described in the first embodiment will be denoted by the same reference numerals, and the description thereof will also be omitted.

  As shown in FIG. 3, in the refrigeration apparatus 1 according to the second embodiment of the present invention, the liquid tank 2 includes a liquid chamber that stores the heat medium liquid for each of the refrigerators 4 of the B system, the C system, and the D system, That is, it has a total of three liquid chambers R1. These liquid chambers R1 are formed by dividing the liquid tank 2 by a partition wall.

  Each liquid chamber R1 is individually provided with a heat exchanger 4c of the B system, the C system, and the D system. Each liquid chamber R1 is provided with a temperature detector 2a. These temperature detectors 2 a are provided in the heat medium liquid and are individually provided on the inner wall of each liquid chamber R 1, and are electrically connected to the control unit 5. Each temperature detector 2 a detects the temperature of the heat medium liquid in each liquid chamber R 1 and inputs it to the control unit 5. As each temperature detector 2a, various temperature sensors can be used.

  In addition to the compressor 3a and the condenser 3b, the A-system refrigerator 3 includes an expansion valve 3c, a heat exchanger 3d, and an on-off valve 11 for each liquid chamber R1. Accordingly, the refrigerant pipe 3e is formed so as to connect the expansion valve 3c, the heat exchanger 3d, and the on-off valve 11 in parallel to the compressor 3a and the condenser 3b.

  Next, the cooling process performed by the refrigeration apparatus 1 will be described. In addition, the control part 5 of the freezing apparatus 1 performs a cooling process based on various programs and various information.

  As shown in FIG. 4, first, the temperature of the refrigerant that cools the heat medium liquid is set for each liquid chamber R1 according to the season (step S11). For example, when the season is summer, the refrigerant temperature for each liquid chamber R1 is set lower than when the season is spring or autumn. In addition, when the season is winter, the refrigerant temperature for each liquid chamber R1 is set higher than when the season is spring or autumn. In this way, by changing the refrigerant temperature for each liquid chamber R1 according to the season, the power consumption of the A-system refrigerator 3 can be suppressed as compared with the case where the refrigerant temperature in the summer season is used over the four seasons. It becomes possible.

  Next, after the processing of step S11, it is determined whether or not the temperature of the heat medium liquid is higher than the set temperature for each liquid chamber R1 (step S12). The temperature of the heat medium liquid for each liquid chamber R1 is constantly detected by each temperature detector 2a and input to the control unit 5. The set temperature for each liquid chamber R1 is determined so as to be lower than the temperature of each refrigerant in the B system, the C system, and the D system. Thereby, the supercooling with respect to each refrigerant | coolant of B system | strain, C system | strain, and D system | strain is attained.

  If it is determined in step S12 that the temperature of the heat medium liquid for each liquid chamber R1 is higher than the set temperature (YES in step S12), the temperature of the heat medium liquid is set in the B system, the C system, and the D system. The on-off valve 12 of the system related to the liquid chamber R1 higher than the temperature is closed, and the on-off valve 13 is opened (step S13). Further, in the A system, the on-off valve 11 related to the liquid chamber R1 in which the temperature of the heat medium liquid is higher than the set temperature is opened (step S14), and then the process is repeated from step S12.

  Thereby, in the system corresponding to the liquid chamber R1 in which the temperature of the heat medium liquid is higher than the set temperature among the B system, the C system, and the D system, the refrigerant flowing through the refrigerant pipe 4e does not pass through the heat exchanger 4c. It is directly supplied to the cooler 4d (without supercooling). Further, in the A chamber, in the liquid chamber R1 where the temperature of the heat medium liquid is higher than the set temperature, heat exchange between the refrigerant flowing in the refrigerant pipe 3e and the heat medium liquid in the liquid chamber R1 is heat exchange in the liquid chamber R1. The heat medium liquid in the liquid chamber R1 is cooled until the temperature reaches the set temperature (cooling of the heat medium liquid).

  On the other hand, in step S12, when it is determined that the temperature of the heat medium liquid for each liquid chamber R1 is not higher than the set temperature, that is, lower than the set temperature (NO in step S12), the B system, the C system, and the D system Among them, the on-off valve 13 of the system related to the liquid chamber R1 in which the temperature of the heat medium liquid is equal to or lower than the set temperature is closed, and the on-off valve 12 is opened (step S15). Furthermore, in the A system, the on-off valve 11 related to the liquid chamber R1 in which the temperature of the heat medium liquid is equal to or lower than the set temperature is closed (step S16), and then the process is repeated from step S12.

  Thereby, in the system corresponding to the liquid chamber R1 in which the temperature of the heat medium liquid is equal to or lower than the set temperature among the B system, the C system, and the D system, the refrigerant flowing through the refrigerant pipe 4e is the heat exchanger in the liquid chamber R1. It is supercooled by 4c and supplied to the cooler 4d (supercooling execution). By supercooling this refrigerant, it is possible to improve the refrigeration capacity of each refrigerator 4 and realize energy saving. Further, in the system A, in the liquid chamber R1 in which the temperature of the heat medium liquid is equal to or lower than the set temperature, the refrigerant stops flowing through the refrigerant pipe 3e, and the refrigerant in the refrigerant pipe 3e and the heat medium liquid in the liquid chamber R1 The heat exchange is not executed, and the heat medium liquid in the liquid tank 2 is not cooled (the heat medium liquid is not cooled).

  Thus, in the B system, the C system, and the D system, the refrigeration capacity of the refrigerator 4 is increased by supercooling. Thereby, it is possible to reduce the horsepower of the refrigerator 4 for energy saving, and it is also possible to reduce the refrigerant charging amount. Further, by performing the supercooling operation, it is possible to reduce the amount of power used at the peak time, and as a result, the basic charge can be reduced. In addition, power leveling can be achieved by using nighttime power with respect to the A-system refrigerator 3.

  As described above, according to the second embodiment, the same effect as that of the first embodiment can be obtained. Furthermore, since it becomes possible to supercool a refrigerant | coolant for every refrigerator 4 of B system, C system, and D system, the refrigerant | coolant of each system of B system, C system, and D system can be reliably subcooled. . As a result, energy saving performance can be improved with certainty.

  Further, in the A-system refrigerator 3, the temperature of the heat medium liquid in the liquid chamber R1 is adjusted for each liquid chamber R1 in accordance with the cooling load for each of the B-system, C-system, and D-system refrigerators 4. Thereby, for example, even when the refrigerators 4 of the B system, the C system, and the D system are refrigerators having different cooling temperatures, such as refrigerated foods, frozen foods, and fresh foods, the heating medium liquid is used according to the cooling load. By adjusting the temperature, it is possible to reliably supercool the refrigerant of each of the refrigerators 4 in the B system, the C system, and the D system, so that the energy saving performance can be reliably improved.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. For example, some constituent elements may be deleted from all the constituent elements shown in the above-described embodiment, and further, constituent elements over different embodiments may be appropriately combined.

DESCRIPTION OF SYMBOLS 1 Refrigeration apparatus 2 Liquid tank 2a Temperature detector 3 Refrigerator 3a Compressor 3b Condenser 3c Expansion valve 3d Heat exchanger 3e Refrigerant piping 4 Refrigerator 4a Compressor 4b Condenser 4c Heat exchanger 4d Cooler 4e Refrigerant piping 4f Bypass Piping 5 Control unit 11 On-off valve 12 On-off valve 13 On-off valve R1 Liquid chamber

Claims (7)

A liquid tank for storing the heat medium liquid;
A refrigerating machine having a refrigerant circulation channel through which the refrigerant circulates, and cooling the heat medium liquid in the liquid tank by heat exchange between the heat medium liquid in the liquid tank and the refrigerant flowing in the refrigerant circulation channel;
A plurality of refrigerant circulation passages through which the refrigerant circulates, and heat-exchange between the heat medium liquid in the liquid tank and the refrigerant flowing through the refrigerant circulation passage to supercool the refrigerant flowing through the refrigerant circulation passage. A refrigerator,
A refrigeration apparatus comprising:   The refrigerating apparatus according to claim 1, wherein the refrigerator that cools the heat medium liquid changes a temperature of a refrigerant that performs heat exchange with the heat medium liquid in the liquid tank according to a season. A temperature detector for detecting the temperature of the heat medium liquid in the liquid tank;
The refrigerator that supercools the refrigerant limits supercooling of the refrigerant according to the temperature of the heat medium liquid in the liquid tank detected by the temperature detector. Refrigeration equipment.   The refrigerating apparatus according to any one of claims 1 to 3, wherein the refrigerator that cools the heat medium liquid includes a compressor, and the compressor is controlled by an inverter. The refrigerator that cools the heat medium liquid is a small-sized medium temperature refrigerator that performs refrigeration smaller than a refrigerator that has superpower cooling the refrigerant.
The refrigeration apparatus according to any one of claims 1 to 4, wherein the refrigerator that supercools the refrigerant is a low-temperature refrigerator that performs refrigeration. The liquid tank has a liquid chamber for storing a heat medium liquid for each refrigerator that supercools the refrigerant,
The refrigerator that cools the heat medium liquid includes a heat exchanger that performs heat exchange between the heat medium liquid in the liquid chamber and the refrigerant that flows through the refrigerant circulation passage for each liquid chamber.
6. The refrigerator that supercools the refrigerant has a heat exchanger that performs heat exchange between the heat medium liquid in the liquid chamber and the refrigerant flowing through the refrigerant circulation passage. The refrigeration apparatus according to any one of the above.   The refrigerator that cools the heat medium liquid adjusts the temperature of the heat medium liquid in the liquid chamber for each liquid chamber according to a cooling load for each refrigerator that supercools the refrigerant. The refrigeration apparatus described.

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