JP5024210B2 - Refrigerant cooling circuit - Google Patents

Description

  The present invention relates to a refrigerant cooling circuit provided in a cup-type vending machine that prepares and sells a cup beverage by providing a cooling water tank that cools syrup and dilution water and an auger-type ice maker that cools drinking water to produce ice. Is.

  There is known a cup-type vending machine that sells a cold beverage prepared by adding ice to a mixture of syrup and diluted water. In such a cup-type vending machine, when money is inserted and the cold beverage selection button is pressed, the syrup and dilution water cooled in the cooling water tank are injected and mixed into the cup supplied from the cup supply device, In addition, cold beverages that have been adjusted by placing ice that has been made and stored in an auger type ice maker are sold to users from the sales outlet. In this way, in order to sell and sell cold drinks in cup-type vending machines, a cooling water tank that cools syrup and dilution water, an auger ice maker that cools drinking water and produces ice, a cooling water tank, A refrigerant cooling circuit for cooling the auger type ice making machine is provided.

  In the cooling water tank, side surfaces and a bottom surface are constituted by heat insulating walls, and cooling water for cooling syrup and dilution water is stored in a substantially rectangular parallelepiped water tank opened upward. Then, the evaporation pipe (hereinafter referred to as “cold water evaporator”) of the refrigerant cooling circuit in which the metal pipe is wound in a coil shape is immersed in the cooling water, and the cold water is evaporated by the latent heat of vaporization (heat of vaporization) generated when the refrigerant is evaporated. An ice bank (ice block) is formed in the peripheral area of the vessel, and the temperature of the cooling water is maintained at approximately 0 ° C. by using the heat storage of the ice bank. Furthermore, in the cooling water in the vicinity of the cold water evaporator, a plurality of stainless steel pipes are coiled so as to correspond to the number of syrups and dilution water that are the raw materials of cold beverages sold by the cooling pipes.

In addition, an auger type ice maker that produces ice to be used when preparing cold beverages is an ice making unit that cools drinking water supplied from a drinking water tank to make ice, and an ice storage unit that stores the ice produced on a cocoon child. It consists of and.
The ice making unit includes a drive motor, an auger (screw-like rotary cutting blade) connected via a speed reducer that reduces and transmits the rotation of the drive motor, an ice making cylinder through which the auger is inserted, an ice making cylinder A refrigerant cooling circuit evaporation pipe (hereinafter referred to as an “ice-making evaporator”) wound around the outer peripheral surface, an ice compression extrusion head provided above the auger, and an insulating material surrounding the ice-making cylinder and the ice-making evaporator. The potable water supplied from the potable water tank by the latent heat of evaporation of the refrigerant flowing through the ice making evaporator wound around the outer surface of the ice making cylinder is icing on the inner wall surface of the ice making cylinder. The ice is made by rotating the auger while scraping it off with an auger and compressing it with an extrusion head.

The ice storage section has an ice storage chamber composed of a heat insulating wall with a circular cross section at the top of the ice making section. Inside the ice storage section is an agitator for stirring ice pieces attached to a rotating shaft coaxial with the auger, an agitator and ice storage It is equipped with an ice-loading cocoon (having the role of draining the melted water in which the ice melts) disposed between the bottom of the chamber.
The refrigerant cooling circuit includes a compressor that compresses refrigerant as a working medium, a radiator that radiates the refrigerant supplied from the compressor, an expansion valve that squeezes and expands the refrigerant supplied from the radiator, and cooling the cooling water tank A cold water evaporator immersed in water, a cold water refrigerant valve for supplying refrigerant to the cold water evaporator, an ice making evaporator wound around the outer peripheral surface of an ice making cylinder of an auger type ice making machine, and a refrigerant to the ice making evaporator It consists of an ice-making refrigerant valve to be supplied and a refrigerant pipe that allows the refrigerant to flow through each of the devices. The refrigerant supplied to the cold water evaporator and the ice-making evaporator generates latent heat of evaporation when it evaporates. Then, the refrigerant returns to the compressor, and the refrigerant compressed again by the compressor is sent to the radiator.

  The cup-type vending machine needs to suppress the maximum power consumption from the viewpoint of power supply capacity and energy saving, and the cooling capacity of the compressor of the refrigerant cooling circuit is the ice bank in the cooling water tank in order to make it compact and inexpensive. When the demand for ice bank formation arises, the chilled water refrigerant valve is opened and the ice making refrigerant valve is kept closed while the ice making refrigerant valve is closed. The apparatus is operated, and when ice making is requested, the cold water refrigerant valve is kept closed and the ice making refrigerant valve is opened to operate the compressor and the blower to make ice.

  For example, if the ice storage amount of the auger type ice maker exceeds the predetermined amount and the ice bank amount of the cooling water tank becomes less than the predetermined amount, the compressor and the air blower are started and at the same time the ice making refrigerant valve is closed and the cold water refrigerant valve is opened. The refrigerant compressed by the compressor is evaporated by the cold water evaporator, and the ice bank amount is increased by the latent heat of evaporation. In this way, when the ice bank amount exceeds a predetermined amount, the compressor and the blower are stopped and simultaneously the cold water refrigerant valve is closed. Also, when the ice storage amount of the auger type ice maker becomes less than the predetermined amount, the compressor and the air blower are started and at the same time the chilled water refrigerant valve is closed and the ice making refrigerant valve is opened, so that the refrigerant passing through the ice making refrigerant valve is evaporated. The evaporation water is evaporated from the pot, and the drinking water supplied from the potable water tank is iced on the inner wall surface of the ice making cylinder, and the thin ice on the inner wall surface of the ice making cylinder is pushed up while rotating with an auger and compressed by the extrusion head. Then, ice making is performed, and when the amount of stored ice exceeds a predetermined amount, the compressor and the air blower are stopped and the ice making refrigerant valve is also closed.

  Also, when an ice bank formation request and an ice making request occur simultaneously, the compressor and the air blower are operated to open the cold water refrigerant valve and the ice making refrigerant valve alternately, and the ice bank formation of the cooling water tank and the auger type ice making machine are opened. Ice making is performed alternately, and when the amount of ice bank and the amount of stored ice exceeds a predetermined amount, the compressor and the air blower are stopped and the refrigerant valve is also closed (see, for example, Patent Document 1).

As described above, a specific chlorofluorocarbon refrigerant (CFC) is used as a refrigerant used in a refrigerant cooling circuit for forming an ice bank in a cooling water tank or making ice in an auger type ice making machine. Production and use are prohibited because the layer is destroyed, and alternative chlorofluorocarbon refrigerants such as HFC have been used since then, but these do not destroy the ozone layer, but have a high global warming potential and point out environmental problems Has been. Therefore, in recent years, cooling devices using refrigerants having a zero ozone depletion coefficient and a small global warming coefficient have been developed in many fields, and some use natural refrigerants such as carbon dioxide.
JP-A-8-287345

  In the ice making evaporator, the temperature may rise due to heat entering the ice making unit during ice making standby (particularly in summer), but the carbon dioxide refrigerant has a low critical temperature of about 31 ° C., so an auger type ice making machine. When the auger ice maker is started in this state, the ambient temperature tends to be higher than the critical temperature of the carbon dioxide refrigerant, the refrigerant in the ice making evaporator becomes supercritical, and the time from the start until the ice making evaporator is cooled. take time. In this state, if the expansion valve opening is reduced to lower the evaporation temperature, the refrigerant flow from the high pressure side to the low pressure side is throttled, so the low pressure side refrigerant decreases and the high pressure side refrigerant increases. Thus, an overload state in which the high-pressure side pressure of the refrigerant cooling circuit increases and the low-pressure side pressure decreases occurs, and in some cases, the protection circuit of the compressor may be activated and cannot be started.

  Also, when the ambient temperature of the auger type ice maker is high, the ice making evaporator has a high temperature in the ice making section due to heat intrusion during ice making standby, so that the refrigerant flowing into the ice making evaporator at the time of startup rapidly The refrigerant that has evaporated and returned from the ice making evaporator is compressed by the compressor and rapidly sent to the high pressure side. For this reason, the low-pressure side refrigerant is reduced, and an overload state in which the low-pressure side pressure of the refrigerant cooling circuit is reduced and the high-pressure side pressure is increased may occur.

  Furthermore, when the ambient temperature of a cup-type vending machine is high, such as in summer, the temperature of the air that cools the radiator also increases, but the refrigerant cooling circuit that uses carbon dioxide as the refrigerant has an ambient temperature that is less than the critical temperature of carbon dioxide. If it exceeds, it becomes a supercritical state and phase change does not occur, so the heat exchange efficiency in the radiator decreases and the cooling capacity decreases, so the power consumption increases due to the increase in the operating rate of the refrigerant cooling circuit, and the amount of ice making Decrease. When the amount of ice making is reduced when such a large amount of ice in the summer is required, or the operation of the refrigerant cooling circuit is stopped, a problem such as loss of beverage sales opportunities arises.

  In view of the above circumstances, an object of the present invention is to provide a refrigerant cooling circuit capable of securing a cooling capacity using a refrigerant having little influence on the global environment.

To achieve the above object, a refrigerant cooling circuit according to claim 1 of the present invention includes a compressor that compresses a refrigerant, a radiator that dissipates heat in a supercritical pressure state of the refrigerant supplied from the compressor, and In a refrigerant cooling circuit having an expansion mechanism that squeezes and expands a refrigerant supplied from a radiator, and an evaporator that evaporates the refrigerant supplied from the expansion mechanism and returns the refrigerant to the compressor.
The ice-making and chilled water refrigerant valves that allow the refrigerant to flow in and out of the ice-making evaporator and the chilled water evaporator, which are connected in parallel in a manner that allows the ice maker and the cooling water tank to be independently cooled, and the internal temperature of the refrigerator are measured. An internal temperature detecting means for outputting a temperature signal, an ice making refrigerant inlet pipe temperature detecting means for measuring a refrigerant inlet pipe temperature of the ice making evaporator and outputting a temperature signal, the ice making refrigerant valve and the cold water refrigerant valve. Control means for controlling opening and closing,
When the ice making machine is started, the control means controls opening and closing of the ice making refrigerant valve and the cold water refrigerant valve based on temperature signals output from the internal temperature detecting means and the ice making refrigerant inlet pipe temperature detecting means. The refrigerant supplied to the ice making evaporator is cooled by a low-temperature refrigerant staying in the cold water evaporator.

A refrigerant cooling circuit according to a second aspect of the present invention is the refrigerant cooling circuit according to the first aspect, wherein the refrigerant outlet pipe of the cold water evaporator is provided with a cold water refrigerant outlet valve, and the refrigerant is stored in the cold water evaporator. To do.
According to a third aspect of the present invention, there is provided a refrigerant cooling circuit according to the first aspect, wherein the ice making evaporator cooler for cooling the ice making evaporator and the temperature of the refrigerant pipe of the ice making evaporator are measured and the temperature signal is measured. An ice making evaporator temperature detecting means for outputting the cooling water stored in the cooling water tank to the ice making evaporator cooler based on a temperature signal output by the ice making evaporator temperature detecting means. The ice making evaporator is cooled.

A refrigerant cooling circuit according to a fourth aspect of the present invention is the refrigerant cooling circuit according to the first aspect, wherein the cooling water stored in the cooling water tank is disposed around a refrigerant pipe line that communicates the compressor and the expansion mechanism. It cools the refrigerant | coolant which sends water and flows through the said refrigerant | coolant pipeline.
A refrigerant cooling circuit according to a fifth aspect of the present invention is the refrigerant cooling circuit according to any one of the first to fourth aspects described above, wherein the refrigerant is carbon dioxide.

  According to the first aspect of the present invention, when the internal temperature is equal to or higher than the carbon dioxide refrigerant critical temperature at the initial stage of starting the auger type ice making machine, the ice making refrigerant valve and the cold water refrigerant valve are opened, and the compressor is operated to drive the expansion mechanism. By variably controlling the valve opening / closing amount, the refrigerant held at a low temperature (approximately 0 ° C.) in the cold water evaporator immersed in the cooling water stored in the cooling water tank is circulated through the refrigerant pipe. Since the low-temperature refrigerant flows into the internal heat exchanger and exchanges heat with the high-pressure side high-temperature refrigerant flowing from the radiator to the internal heat exchanger, the temperature of the high-temperature refrigerant sent to the expansion mechanism can be lowered. , It can prevent rapid temperature rise of the high-pressure side refrigerant, can prevent the pressure rise due to the refrigerant amount drop in the ice making evaporator being hot and excessive refrigerant movement to the high-pressure side, and overload State or get stuck It is possible to prevent, using less carbon dioxide refrigerant influence on the global environment, it is possible to provide a refrigerant cooling circuit capable of ensuring the cooling capacity.

According to the second aspect of the present invention, when the internal temperature is equal to or higher than the carbon dioxide refrigerant critical temperature at the initial stage of starting the auger type ice making machine, the refrigerant in the cold water evaporator held at low pressure and low temperature is released. As a result, the high-temperature refrigerant on the high-pressure side is immediately cooled in the internal heat exchanger, and the normal operation state can be quickly achieved.
According to the invention of claim 3, based on the ice making evaporator refrigerant pipe temperature, the cooling water pump is driven to store the cooling water of approximately 0 ° C. stored in the cooling water tank into the ice making evaporator cooler through the cooling water circulation path. By sending water and cooling the refrigerant of the ice making evaporator, the carbon dioxide refrigerant in the ice making evaporator is cooled below the critical temperature by the cooling water cooled to approximately 0 ° C. Therefore, the ice making evaporator and the auger using the refrigerant are cooled. The temperature drop of the ice making water in the ice making cylinder of the type ice making machine can proceed rapidly, preventing an increase in pressure due to excessive refrigerant movement to the high pressure side of the carbon dioxide refrigerant, and avoiding an overload condition .

  According to a fourth aspect of the present invention, based on the heat exchanger refrigerant tube temperature, the cooling water pump is driven to store the cooling water at approximately 0 ° C. stored in the cooling water tank in the cooling water circulation path. By cooling the refrigerant flowing into the internal heat exchanger and cooling the refrigerant flowing into the internal heat exchanger, the carbon dioxide refrigerant flowing from the internal heat exchanger to the ice making evaporator is cooled below the critical temperature. Therefore, the ice making evaporator and the auger type ice making using the refrigerant The temperature drop of the ice making water in the ice making cylinder of the machine quickly proceeds, the pressure increase due to excessive refrigerant movement of the carbon dioxide refrigerant to the high pressure side can be prevented, and the overload state can be avoided.

  According to the invention of claim 5, since the refrigerant is carbon dioxide, it is possible to provide a refrigerant cooling circuit using a refrigerant having little influence on the global environment.

Exemplary embodiments of a refrigerant cooling circuit according to the present invention will be explained below in detail with reference to the accompanying drawings. Note that the present invention is not limited to the embodiments.
(Embodiment 1)
FIG. 1 is a conceptual view in which a cup-type vending machine is provided with a refrigerant cooling circuit according to Embodiment 1 of the present invention. As shown in FIG. 1, the refrigerant cooling circuit 10 includes a two-stage compressor (compressor) 11, an intermediate heat exchanger 12, a gas cooler (heat radiator) 13, a blower 14, an internal heat exchanger 15, and an electronic expansion valve. (Expansion mechanism) 16, ice making refrigerant valve 17, ice making evaporator 18, cold water refrigerant valve 19, cold water evaporator 20, and refrigerant pipe L connecting them, and cooling by circulating the refrigerant. . Here, as the refrigerant, carbon dioxide having non-flammability, safety, and non-corrosive properties and further having no influence on the global environment that does not destroy the ozone layer is used.

  The two-stage compressor 11 compresses the low-temperature and low-pressure refrigerant (carbon dioxide) returned from the internal heat exchanger 15 into a high-temperature and high-pressure supercritical refrigerant. The two-stage compressor 11 is a compressor that compresses refrigerant in two steps, a first compressor 11a that performs first refrigerant compression, and a second compressor 11b that performs second refrigerant compression. The intermediate heat exchanger 12 is provided between the first compressor 11a and the second compressor 11b. The intermediate heat exchanger 12 radiates the high-temperature and high-pressure refrigerant compressed by the first compressor 11a and supplies it to the second compressor 11b. In this way, the intermediate heat exchanger 12 is provided between the first compressor 11a and the second compressor 11b of the two-stage compressor 11 that compresses the refrigerant in two steps, and the first compressor 11a When the compressed high-temperature and high-pressure (for example, 80 ° C., 6 MPa) refrigerant is radiated by the intermediate heat exchanger 12 and cooled (for example, cooled by 20 degrees from 80 ° C. to 60 ° C.) and compressed by the second compressor 11b, Since the refrigerant compression load of the two-compressor 11b can be reduced and the cooling efficiency can be improved, the power consumption is reduced to a supercritical refrigerant having a desired high temperature and high pressure (for example, 90 to 100 ° C., 10 MPa). It becomes possible to do. The two-stage compressor 11 is connected to an inverter 11 c that converts the frequency of the power source, and the two-stage compressor 11 is operated at an appropriate power source frequency corresponding to the heat load of the refrigerant cooling circuit 10. As the two-stage compressor 11, a reciprocating compressor, a rotary compressor, a scroll compressor, or the like is appropriately applied.

The gas cooler 13 cools (dissipates heat) the refrigerant supplied from the two-stage compressor 11 to a temperature (for example, 40 ° C.) close to the ambient temperature, and is cooled by the air taken in from the outside by the blower 14. It is.
The internal heat exchanger 15 returns to the two-stage compressor 11 from the refrigerant (for example, 40 ° C., 10 MPa) cooled to a temperature close to the ambient temperature supplied from the gas cooler 13 and the ice making evaporator 18 or the cold water evaporator 20. Heat exchange with a low-temperature and low-pressure refrigerant (for example, 0 ° C., 3 MPa) to be performed, and inside thereof, a refrigerant pipe 15a through which the refrigerant supplied from the gas cooler 13 flows, and an ice making evaporator 18 or cold water evaporation The refrigerant pipe 15b through which the refrigerant evaporated in the vessel 20 flows is arranged in such a manner that heat can be exchanged with each other, and the refrigerant flowing through the refrigerant pipe 15a is cooled (for example, 35 ° C., 10 MPa). ) The refrigerant supplied to the electronic expansion valve 16 and flowing through the refrigerant line 15b is warmed (for example, 25 to 30 ° C., 3 MPa) and returned to the two-stage compressor 11.

The electronic expansion valve 16 squeezes and expands the refrigerant heat-exchanged by the internal heat exchanger 15 to reduce the pressure and adjust it to a low-temperature and low-pressure (for example, −10 ° C., 3 MPa) state to adjust the ice making evaporator 18 or the cold water evaporator 20. To supply.
The ice making evaporator 18 is wound around the outer peripheral surface of the ice making cylinder of the auger type ice making machine 21 and is generated when the low temperature and low pressure refrigerant supplied from the electronic expansion valve 16 evaporates when the ice making refrigerant valve 17 is opened. Drinking water supplied from the potable water tank is caused to accumulate on the inner wall surface of the ice-making cylinder by the latent heat of evaporation, and the ice inside the ice-making cylinder wall surface is pushed up while scraping it by rotating the auger and compressed by the extrusion head to produce ice. To do. Further, the ice making evaporator 18 is detachably coupled to the refrigerant line L by a self-sealing quick coupling 22.

  The cold water evaporator 20 is wound at a cooling water W stored in the cooling water tank 23 by winding a metal pipe in a coil shape. When the cold water refrigerant valve 19 is opened, the low temperature supplied from the electronic expansion valve 16 is reduced. An ice bank (ice block) B is formed around the latent heat of evaporation generated when the low-pressure refrigerant evaporates, and the temperature of the cooling water W is maintained at approximately 0 ° C. by using the heat stored in the ice bank B. A carbonator (not shown) immersed in the water W and the cooling pipe 24 for syrup and dilution water are cooled, and the syrup and dilution water flowing through and the carbonated water in the carbonator are cooled.

The refrigerant cooling circuit 10 also includes an internal temperature sensor (internal temperature detecting means) 25 that measures the internal temperature of the cup type vending machine and outputs a temperature signal, and the refrigerant inlet pipe temperature of the ice making evaporator 18. And an ice making refrigerant inlet pipe temperature sensor (ice making refrigerant inlet pipe temperature detecting means) 26 for measuring and outputting a temperature signal.
FIG. 2 is a block diagram showing a control system of the refrigerant cooling circuit 10. As shown in the figure, the control unit (control means) 90 is provided with a memory 96 and a timer 97. The control unit 90 includes a program and data stored in the memory 96, a timer 97, an internal temperature sensor 25 that measures the internal temperature of the cup type vending machine and outputs a temperature signal, and the refrigerant of the ice making evaporator 18. A signal is output based on an input signal from an ice making refrigerant inlet pipe temperature sensor 26 that measures the inlet pipe temperature and outputs a temperature signal, and operates the two-stage compressor 11, the blower 14, and the auger type ice maker 21. It is driven to variably control the opening / closing amount of the electronic expansion valve 16, and to open / close the ice making refrigerant valve 17 and the cold water refrigerant valve 19.

With this configuration, the contents of the processing executed by the control unit 90 based on the temperature signals output from the internal temperature sensor 25 and the ice making refrigerant inlet pipe temperature sensor 26 of the refrigerant cooling circuit 10 of the present invention are shown in the flowchart of FIG. This will be described with reference to the refrigerant circulation diagram and the timing chart of FIG.
When the ice storage amount of the auger type ice making machine 21 indicates a predetermined amount or less (step S101: Y), the controller 90 compares the internal temperature output from the internal temperature sensor 25 with the carbon dioxide refrigerant critical temperature (step S102). ).

<Inside temperature> Refrigerant critical temperature>
When the internal temperature output from the internal temperature sensor 25 is equal to or higher than the carbon dioxide refrigerant critical temperature (approximately 31 ° C.) (step S102: Y), the ice-making refrigerant valve 17 and the cold water refrigerant valve 19 are opened (step S103), and the two-stage type The compressor 11 and the air blower 14 are driven to variably control the valve opening / closing amount of the electronic expansion valve 16 (step S104). When the ice-making refrigerant valve 17 is opened and the chilled water refrigerant valve 19 is also opened and the refrigerant is circulated in the direction indicated by the arrow in FIG. 4, the chilled water evaporator 20 immersed in the cooling water W stored in the cooling water tank 23. The low-temperature (approximately 0 ° C.) refrigerant staying in the refrigerant is circulated through the refrigerant pipe L, and this low-temperature refrigerant flows into the internal heat exchanger 15 and flows into the internal heat exchanger 15 from the gas cooler 13. By exchanging heat with the high-pressure side high-temperature refrigerant, the temperature of the high-temperature refrigerant sent to the electronic expansion valve 16 is lowered, so that a rapid temperature rise of the high-pressure side refrigerant can be prevented.

Next, the refrigerant inlet pipe temperature output from the ice making refrigerant inlet pipe temperature sensor 26 which measures the refrigerant inlet pipe temperature of the ice making evaporator 18 and outputs a temperature signal, and the temperature (To) determined in advance from the experimental results and the like are obtained. Compare (step S105).
<Ice-making evaporator refrigerant inlet pipe temperature <predetermined temperature (To)>
When the refrigerant inlet pipe temperature is higher than a predetermined temperature (To) (step S105: N), the chilled water refrigerant valve 19 is kept open to variably control the valve opening / closing amount of the electronic expansion valve 16 to lower the refrigerant inlet pipe temperature. Go. Then, as shown in FIG. 5, when the refrigerant inlet pipe temperature becomes lower than a predetermined temperature (To) (step S105: Y), the cold water refrigerant valve 19 is closed and the ice-making refrigerant valve 17 is kept open (step S106). The operation of the auger type ice making machine 21 is continued by variably controlling the valve opening / closing amount of the electronic expansion valve 16 (step S107). When the ice storage amount of the auger type ice making machine 21 reaches a predetermined amount, the ice making operation by the control unit 90 is terminated (step S108: Y).

  When the internal temperature output from the internal temperature sensor 25 is lower than the carbon dioxide refrigerant critical temperature (approximately 31 ° C.) (step S102: N), only the ice-making refrigerant valve 17 is opened (step S109). The compressor 11 and the air blower 14 are driven to variably control the valve opening / closing amount of the electronic expansion valve 16 (step S110). Then, the operation of the auger type ice making machine 21 is continued by variably controlling the valve opening / closing amount of the electronic expansion valve 16 (step S111). When the ice storage amount of the auger type ice making machine 21 reaches a predetermined amount, the ice making operation by the control unit 90 is terminated (step S112: Y).

As described above, when the internal temperature output from the internal temperature sensor 25 at the initial start of the auger type ice making machine 21 is equal to or higher than the carbon dioxide refrigerant critical temperature (approximately 31 ° C.), the ice making refrigerant valve 17 and the cold water refrigerant valve 19 are opened. The chilled water evaporator immersed in the cooling water W stored in the cooling water tank 23 by operating and driving the two-stage compressor 11 and the blower 14 to variably control the valve opening / closing amount of the electronic expansion valve 16. The refrigerant kept at a low temperature (approximately 0 ° C.) in the refrigerant 20 is circulated through the refrigerant pipe L, and this low-temperature refrigerant flows into the internal heat exchanger 15 and flows into the internal heat exchanger 15 from the gas cooler 13. Since the temperature of the high-temperature refrigerant sent to the electronic expansion valve 16 is reduced by exchanging heat with the high-temperature side high-temperature refrigerant, it is possible to prevent a rapid increase in the temperature of the high-pressure side refrigerant, and the ice making evaporation that is at a high temperature The amount of refrigerant in the vessel 18 The pressure rise due to excessive refrigerant movement to the high-pressure side can be prevented, and it can be prevented from overloading or becoming unable to start, so the cooling capacity is reduced by using carbon dioxide refrigerant that has little impact on the global environment. It is possible to provide a refrigerant cooling circuit capable of ensuring the above.
(Embodiment 2)
Next, the refrigerant cooling circuit 30 according to the second embodiment of the present invention will be described with reference to FIG. In addition, the same code | symbol is used regarding the same structure as the refrigerant cooling circuit 10 demonstrated in Embodiment 1. FIG.

  As shown in FIG. 6, the refrigerant cooling circuit 30 described in the second embodiment includes a cold water refrigerant outlet valve in the refrigerant outlet pipe of the cold water evaporator 20 immersed in the cooling water W stored in the cooling water tank 23. 31 is different from the refrigerant cooling circuit 10 in that a cold water refrigerant inlet pipe temperature sensor (cold water refrigerant inlet pipe temperature detecting means) 32 that measures the refrigerant inlet pipe temperature of the cold water evaporator 20 and outputs a temperature signal is provided. is doing.

  FIG. 7 is a block diagram showing a control system of the refrigerant cooling circuit 30. The control unit (control means) 91 includes a program and data stored in the memory 96, a timer 97, an internal temperature sensor 25 that measures the internal temperature of the cup-type vending machine and outputs a temperature signal, ice making evaporation From the ice making refrigerant inlet pipe temperature sensor 26 that measures the refrigerant inlet pipe temperature of the cooler 18 and outputs a temperature signal, and from the cold water refrigerant inlet pipe temperature sensor 32 that measures the refrigerant inlet pipe temperature of the cold water evaporator 20 and outputs the temperature signal Based on the input signal, the two-stage compressor 11, the air blower 14, and the auger type ice making machine 21 are driven to operate, the valve opening / closing amount of the electronic expansion valve 16 is variably controlled, and the ice making refrigerant valve 17 is operated. The cold water refrigerant valve 19 and the cold water refrigerant outlet valve 31 are controlled to open and close. During the cycle operation, the ice making operation in the auger type ice making machine 21 and the formation of the ice bank in the cooling water tank 23 are sequentially performed, and a mode is set in which the refrigerant flows into the cold water evaporator 20 side when the operation of the refrigerant cooling circuit 30 is completed. More specifically, at the end of the ice bank formation in the cooling water tank 23, the operation of the two-stage compressor 11 is stopped, and at the same time, the cold water refrigerant valve 19 and the cold water refrigerant outlet valve 31 are closed, and low temperature / low pressure refrigerant is supplied to the cold water evaporator 20. Try to stay. At the same time, the ice-making refrigerant valve 17 is opened to prevent the refrigerant cooling circuit 30 from being blocked on the low pressure side, so that the refrigerant pressure on the high pressure / low pressure side is balanced.

FIG. 8 shows the contents of the processing executed by the control unit 91 based on the temperature signals output from the internal temperature sensor 25, the refrigerant inlet pipe temperature sensor 26, and the cold water refrigerant inlet pipe temperature sensor 32 of the refrigerant cooling circuit 30 in this configuration. This will be described with reference to the flowchart of FIG. 9 and the timing chart of FIG.
When the ice storage amount of the auger type ice making machine 21 indicates a predetermined amount or less (step S201: Y), the controller 91 compares the internal temperature output from the internal temperature sensor 25 with the carbon dioxide refrigerant critical temperature (step S202). ).

<Inside temperature> Refrigerant critical temperature>
When the internal temperature output from the internal temperature sensor 25 is equal to or higher than the carbon dioxide refrigerant critical temperature (approximately 31 ° C.) (step S202: Y), the ice-making refrigerant valve 17 is closed with the cold water refrigerant valve 19 and the cold water refrigerant outlet valve 31 closed. Is opened (step S203), and the two-stage compressor 11 and the blower 14 are driven to variably control the opening / closing amount of the electronic expansion valve 16 (step S204).

Next, the refrigerant inlet pipe temperature output from the ice making refrigerant inlet pipe temperature sensor 26 that measures the refrigerant inlet pipe temperature of the ice making evaporator 18 and outputs a temperature signal, and the temperature (θo) determined in advance from the experimental results, etc. Compare (step S205).
<Ice-making evaporator refrigerant inlet pipe temperature <predetermined temperature (θo)>
When the refrigerant inlet pipe temperature is higher than a predetermined temperature (θo) (step S205: N), the ice making refrigerant valve 17 is kept open to variably control the valve opening / closing amount of the electronic expansion valve 16 to lower the refrigerant inlet pipe temperature. Go. Then, as shown in FIG. 10, when the refrigerant inlet pipe temperature becomes lower than the predetermined temperature (θo) (step S205: Y), the cold water refrigerant valve 19 and the cold water refrigerant outlet valve 31 are opened and stored in the cooling water tank 23. A low-temperature (substantially 0 ° C.) refrigerant staying in the cold water evaporator 20 immersed in the cooling water W is circulated through the refrigerant pipe L, and the opening / closing amount of the electronic expansion valve 16 is variably controlled. The operation of the auger type ice making machine 21 is continued (step S206). The reason why the chilled water refrigerant valve 19 and the chilled water refrigerant outlet valve 31 are not immediately opened at the time of starting the auger type ice making machine 21 is that the refrigerant pressure in the chilled water evaporator 20 is low. This is because if it is not low, the refrigerant flows back to the cooling evaporator 20 side. Therefore, the predetermined temperature (θo) needs to be the refrigerant inlet pipe temperature of the ice making evaporator 18 at which the refrigerant low-pressure side pressure becomes equal to or lower than the refrigerant pressure in the cold water evaporator 20. Then, the refrigerant inlet pipe temperature output from the ice making refrigerant inlet pipe temperature sensor 26, which measures the refrigerant inlet pipe temperature of the ice making evaporator 18 and outputs a temperature signal, is compared with the temperature (θ1) determined in advance from the experimental results. (Step S207).

<Ice-making evaporator refrigerant inlet pipe temperature <predetermined temperature (θ1)>
When the refrigerant inlet pipe temperature becomes lower than the predetermined temperature (θ1) (step S207: Y), the cold water refrigerant valve 19 is closed and the cold water refrigerant outlet valve 31 and the ice making refrigerant valve 17 are kept open (step S208). The operation of the auger type ice making machine 21 is continued by variably controlling the valve opening / closing amount of the expansion valve 16 (step S209). When the ice storage amount of the auger type ice making machine 21 reaches a predetermined amount, the ice making operation by the control unit 91 is terminated (step S210: Y).

  Next, referring to FIG. 9, a process for retaining the refrigerant in the cold water evaporator 20 executed by the controller 91 at the end of the ice making operation will be described. At the same time as the ice-making refrigerant valve 17 is closed, the cold water refrigerant valve 17 and the cold water refrigerant outlet valve 31 are opened (step S216), and the refrigerant is caused to flow into the cold water evaporator 20. Then, the refrigerant inlet pipe temperature output from the cold water refrigerant inlet pipe temperature sensor 32 that measures the refrigerant inlet pipe temperature of the chilled water evaporator 20 and outputs a temperature signal is compared with the temperature (θ2) determined in advance from the experimental results. (Step S217).

<Cold water evaporator refrigerant inlet pipe temperature <predetermined temperature (θ2)>
When the refrigerant inlet pipe temperature becomes lower than the predetermined temperature (θ2) (step S217: Y), the two-stage compressor 11 is stopped, the cold water refrigerant valve 17 and the cold water refrigerant outlet valve 31 are closed, and the ice making refrigerant The valve 17 is temporarily opened (step S218).
When the internal temperature output from the internal temperature sensor 25 is lower than the carbon dioxide refrigerant critical temperature (approximately 31 ° C.) (step S202: N), only the ice-making refrigerant valve 17 is opened (step S212). The compressor 11 and the air blower 14 are driven to variably control the valve opening / closing amount of the electronic expansion valve 16 (step S213). Then, the operation of the auger type ice making machine 21 is continued by variably controlling the valve opening / closing amount of the electronic expansion valve 16 (step S214). When the ice storage amount of the auger type ice making machine 21 reaches a predetermined amount, the ice making operation by the control unit 91 is terminated (step S215: Y).

As described above, when the internal temperature output from the internal temperature sensor 25 at the initial start of the auger type ice making machine 21 is equal to or higher than the carbon dioxide refrigerant critical temperature (approximately 31 ° C.), the cold water refrigerant valve 19 and the cold water refrigerant outlet valve 31 are set. In the closed state, the ice-making refrigerant valve 17 is opened, the two-stage compressor 11 and the air blower 14 are operated and controlled to variably control the valve opening / closing amount of the electronic expansion valve 16, and ice making is started. When the temperature becomes lower than the set temperature (θo), the chilled water refrigerant valve 19 and the chilled water refrigerant outlet valve 31 are opened because the amount of the refrigerant circulating in the refrigerant pipe L at the beginning of the auger type ice making machine 21 starts up in the chilled water evaporator 20. Since the refrigerant is reduced by being retained at a low temperature and a low pressure, an increase in the high-pressure side pressure can be suppressed, and an overload state can be avoided. Further, the refrigerant in the chilled water evaporator 20 held at a low pressure and a low temperature is released, so that the high-temperature refrigerant on the high-pressure side is immediately cooled in the internal heat exchanger 15 so that the normal operation state can be quickly achieved. Because.
(Embodiment 3)
Next, the refrigerant cooling circuit 40 according to Embodiment 3 of the present invention will be described with reference to FIG. In addition, the same code | symbol is used regarding the same structure as the refrigerant cooling circuit 10 demonstrated in Embodiment 1. FIG.

  As shown in FIG. 11, the refrigerant cooling circuit 40 described in the third embodiment includes an ice making evaporator cooler 41 for cooling the ice making evaporator 18, a cold water pump 42, a drain valve 43, and a cold water circulation path 44. The ice making evaporator 18 includes an ice making evaporator temperature sensor (ice making evaporator temperature detecting means) 45 that measures the temperature of the refrigerant pipe of the ice making evaporator 18 and outputs a temperature signal, and the ice making evaporator temperature sensor 45 outputs the ice making evaporator temperature pipe. The cooling water pump 42 is driven, the cooling water W cooled to approximately 0 ° C. and stored in the cooling water tank 23 is sent to the ice making evaporator cooler 41 through the cooling water circulation path 44, and the refrigerant of the ice making evaporator 18 is sent. This is different from the refrigerant cooling circuit 10 in that it is cooled.

  FIG. 12 is a block diagram showing a control system of the refrigerant cooling circuit 40. As shown in the figure, the control unit (control means) 92 is provided with a memory 96 and a timer 97. The control unit 92 is based on a program and data stored in the memory 96, a timer 97, and an input signal from the ice making evaporator temperature sensor 45 that measures the refrigerant pipe temperature of the ice making evaporator 18 and outputs a temperature signal. The two-stage compressor 11, the blower 14, the auger type ice making machine 21, and the cold water pump 42 are driven to control the opening / closing amount of the electronic expansion valve 16, and the ice making refrigerant valve 17, The cold water refrigerant valve 19 and the drain valve 43 are controlled to open and close.

With this configuration, the contents of the processing executed by the control unit 92 based on the refrigerant pipe temperature signal of the ice making evaporator 18 output from the ice making evaporator temperature sensor 45 of the refrigerant cooling circuit 40 of the present invention are shown in the flowchart of FIG. explain.
When the ice storage amount of the auger type ice making machine 21 is equal to or less than a predetermined amount (step S301: Y), the controller 92 measures the refrigerant pipe temperature of the ice making evaporator 18 and outputs a temperature signal to the ice making evaporator temperature sensor 45. The ice making evaporator refrigerant tube temperature to be output is compared with a temperature (To) determined in advance based on the experimental results and the like (step S302).

<Ice-making evaporator refrigerant tube temperature ≧ predetermined temperature (To)>
When the ice-making evaporator refrigerant pipe temperature is equal to or higher than a predetermined temperature (To) (step S302: Y), the water drain valve 43 is closed (step S303), and the cold water pump 42 is driven (step S304). The stored cooling water W at approximately 0 ° C. is supplied to the ice making evaporator cooler 41 through the cold water circulation path 44 to cool the refrigerant flowing into the ice making evaporator 18, and the ice making evaporator refrigerant tube temperature and the experimental results are used. The temperature is compared with a predetermined temperature (To) (step S305).

<Ice-making evaporator refrigerant tube temperature <predetermined temperature (To)>
When the ice making evaporator refrigerant tube temperature becomes lower than a predetermined temperature (To) (step S305: Y), the water drain valve 43 is opened (step S306), the cooling water W is drawn from the ice making evaporator cooler 41, and the cold water pump 42 is stopped (step S307). Then, the ice making refrigerant valve 17 is opened (step S308), the two-stage compressor 11 is started (step S309), and the auger ice making machine 21 is driven to variably control the valve opening / closing amount of the electronic expansion valve 16. To make ice (step S310). When the ice storage amount of the auger type ice making machine 21 reaches a predetermined amount, the ice making operation by the control unit 92 is terminated (step S311: Y).

Thus, based on the ice-making evaporator refrigerant pipe temperature output from the ice-making evaporator temperature sensor 45 that measures the refrigerant pipe temperature of the ice-making evaporator 18 and outputs a temperature signal, the chilled water pump 42 is driven to the cooling water tank 23. The stored cooling water W at approximately 0 ° C. is supplied to the ice making evaporator cooler 41 through the cold water circulation path 44 to cool the refrigerant in the ice making evaporator 18, thereby cooling the cooling water to approximately 0 ° C. The carbon dioxide refrigerant in the ice making evaporator 18 is cooled to a critical temperature (approximately 31 ° C.) or less by W, and the temperature drop of the ice making water in the ice making evaporator 18 and the auger type ice making machine 21 quickly proceeds. Further, it is possible to prevent an increase in pressure due to excessive refrigerant movement to the high pressure side of the carbon dioxide refrigerant, and to avoid falling into an overload state. Even when the cup-type vending machine ambient temperature is high, the high-pressure refrigerant temperature can be lowered and the decrease in ice making can be prevented, so that even when the demand for ice increases in the summer, it is possible to cope with it.
(Embodiment 4)
Next, a refrigerant cooling circuit 50 according to Embodiment 4 of the present invention will be described with reference to FIG. In addition, the same code | symbol is used regarding the same structure as the refrigerant cooling circuit 40 demonstrated in Embodiment 3. FIG.

  As shown in FIG. 14, the refrigerant cooling circuit 50 described in the fourth embodiment includes an internal heat exchanger cooler 51 that cools a refrigerant pipe of the internal heat exchanger 15, and a refrigerant pipe 15 a of the internal heat exchanger 15. An internal heat exchanger temperature sensor (internal heat exchanger temperature detecting means) 52 that measures temperature and outputs a temperature signal, a chilled water circulation path 54, a chilled water pump 42, and a drain valve 43 are provided, and the internal heat exchanger temperature sensor 52 Based on the temperature of the heat exchanger refrigerant pipe output by the chilled water, the chilled water pump 42 is driven to feed the cooling water W at approximately 0 ° C. stored in the cooling water tank 23 to the internal heat exchanger cooler 51 through the chilled water circulation path 54. The refrigerant cooling circuit 40 is different from the refrigerant cooling circuit 40 in that the refrigerant flowing through the refrigerant pipe 15a is cooled.

  FIG. 15 is a block diagram showing a control system of the refrigerant cooling circuit 50. As shown in the figure, the control unit (control means) 93 is provided with a memory 96 and a timer 97. The controller 93 outputs the program and data stored in the memory 96, the timer 97, and the internal heat exchanger temperature sensor 52 that measures the temperature of the refrigerant pipe 15a of the internal heat exchanger 15 and outputs a temperature signal. A signal is output based on the temperature of the refrigerant pipe of the heat exchanger, and the two-stage compressor 11, the blower 14, the auger ice maker 21, and the cold water pump 42 are operated and driven, and the opening / closing amount of the electronic expansion valve 16 is increased The ice making refrigerant valve 17, the cold water refrigerant valve 19, and the water drain valve 43 are controlled to be opened and closed.

The content of the process which the control part 93 performs based on the heat exchanger refrigerant pipe temperature which the internal heat exchanger temperature sensor 52 of the refrigerant | coolant cooling circuit 50 of this invention outputs with the structure which concerns is demonstrated using the flowchart of FIG. .
When the ice storage amount of the auger type ice making machine 21 is equal to or less than a predetermined amount (step S401: Y), the controller 93 measures the temperature of the refrigerant pipe 15a of the internal heat exchanger 15 and outputs a temperature signal. The heat exchanger refrigerant tube temperature output from the temperature sensor 52 is compared with a temperature (To) determined in advance based on the experimental results (step S402).

<Heat exchanger refrigerant tube temperature ≧ predetermined temperature (To)>
When the heat exchanger refrigerant pipe temperature is equal to or higher than a predetermined temperature (To) (step S402: Y), the water drain valve 43 is closed (step S403), and the cold water pump 42 is driven (step S404). The stored cooling water W at approximately 0 ° C. is sent to the internal heat exchanger cooler 51 through the cold water circulation path 54, the refrigerant flowing into the internal heat exchanger 15 is cooled, and the heat exchanger refrigerant tube temperature and experimental results are obtained. And the like (step S405).

<Heat exchanger refrigerant tube temperature <predetermined temperature (To)>
When the heat exchanger refrigerant pipe temperature becomes lower than the predetermined temperature (To) (step S405: Y), the water drain valve 43 is opened (step S406), the cooling water W is extracted from the internal heat exchanger cooler 51, and the cold water The pump 42 is stopped (step S407). Then, the ice making refrigerant valve 17 is opened (step S408), and the two-stage compressor 11 is started (step S409). Further, the heat exchanger refrigerant tube temperature is compared with a temperature (To) determined in advance based on the experimental results (step S410).

<Heat exchanger refrigerant tube temperature ≧ predetermined temperature (To)>
When the heat exchanger refrigerant pipe temperature is equal to or higher than a predetermined temperature (To) (step S410: Y), the water drain valve 43 is closed (step S411), and the cold water pump 42 is driven (step S412). The stored cooling water W at approximately 0 ° C. is sent to the internal heat exchanger cooler 51 through the cold water circulation path 54 to cool the refrigerant flowing into the internal heat exchanger 15. When the ice storage amount of the auger type ice making machine 21 reaches a predetermined amount (step S413: Y), the water drain valve 43 is opened (step S414), the cooling water W is drained from the internal heat exchanger cooler 51, and the cold water pump 42 is stopped. Then (step S415) the ice making operation is finished. When the ice making is not completed (step S413: N), the auger type ice making machine 21 is driven to variably control the opening / closing amount of the electronic expansion valve 16 to make ice (step S417). When the heat exchanger refrigerant tube temperature becomes lower than the predetermined temperature (To) (step S416: Y), the water drain valve 43 is opened (step S418), and the cooling water W is drained from the internal heat exchanger cooler 51. Then, the cold water pump 42 is stopped (step S419), and the auger type ice making machine 21 is operated and driven to variably control the opening / closing amount of the electronic expansion valve 16 to make ice (step S420). Reaches a predetermined amount (step S421: Y), the operation of the two-stage compressor 11 is stopped (step S422), and the ice making operation by the controller 93 is terminated.

  In this way, the chilled water pump 42 is driven based on the heat exchanger refrigerant pipe temperature output from the internal heat exchanger temperature sensor 52 that measures the temperature of the refrigerant pipe 15a of the internal heat exchanger 15 and outputs a temperature signal. The cooling water W stored in the cooling water tank 23 is supplied to the internal heat exchanger cooler 51 through the cold water circulation path 54 and the refrigerant flowing into the internal heat exchanger 15 is cooled, thereby internal heat exchange. Since the carbon dioxide refrigerant flowing from the vessel 15 into the ice making evaporator 18 is cooled to a critical temperature (approximately 31 ° C.) or less, the temperature of the ice making water in the ice making tubes of the ice making evaporator 18 and the auger type ice making machine 21 is lowered by the refrigerant. Proceeding quickly, it is possible to prevent an increase in pressure due to excessive refrigerant movement of the carbon dioxide refrigerant to the high-pressure side, and it is possible to avoid falling into an overload state. Even when the cup-type vending machine ambient temperature is high, the high-pressure refrigerant temperature can be lowered and the decrease in ice making can be prevented, so that even when the demand for ice increases in the summer, it is possible to cope with it.

It is the schematic which shows the refrigerant cooling circuit in Embodiment 1 of this invention. It is a block diagram which shows the control system of the refrigerant cooling circuit shown in FIG. It is a flowchart which shows control of the refrigerant cooling circuit shown in FIG. FIG. 2 is a refrigerant circulation diagram of the refrigerant cooling circuit shown in FIG. 1. It is a timing chart which shows control of the refrigerant cooling circuit shown in FIG. It is the schematic which shows the refrigerant | coolant cooling circuit in Embodiment 2 of this invention. It is a block diagram which shows the control system of the refrigerant cooling circuit shown in FIG. It is a flowchart which shows control of the refrigerant cooling circuit shown in FIG. It is a flowchart which shows control of the refrigerant cooling circuit shown in FIG. It is a timing chart which shows control of the refrigerant cooling circuit shown in FIG. It is the schematic which shows the refrigerant cooling circuit in Embodiment 3 of this invention. It is a block diagram which shows the control system of the refrigerant | coolant cooling circuit shown in FIG. It is a flowchart which shows control of the refrigerant cooling circuit shown in FIG. It is the schematic which shows the refrigerant cooling circuit in Embodiment 4 of this invention. It is a block diagram which shows the control system of the refrigerant cooling circuit shown in FIG. It is a flowchart which shows control of the refrigerant cooling circuit shown in FIG.

Explanation of symbols

10 Refrigerant cooling circuit 11 Two-stage compressor (compressor)
12 Intermediate heat exchanger 13 Gas cooler (radiator)
14 Blower 15 Internal heat exchanger 16 Electronic expansion valve (expansion mechanism)
17 Ice making refrigerant valve 18 Ice making evaporator 19 Cold water refrigerant valve 20 Cold water evaporator 21 Auger type ice making machine (ice making machine)
23 Chilled water tank 25 Internal temperature sensor (Internal temperature detection means)
26 Ice making refrigerant inlet pipe temperature sensor (ice making refrigerant inlet pipe temperature detecting means)
30 Refrigerant Cooling Circuit 31 Chilled Water Refrigerant Outlet Valve 32 Chilled Water Refrigerant Inlet Tube Temperature Sensor (Cold Water Refrigerant Inlet Tube Temperature Detection Means)
40 Refrigerant Cooling Circuit 41 Ice Maker Evaporator Cooler 42 Chilled Water Pump 43 Drain Valve 44 Chilled Water Circulation Channel 45 Ice Maker Evaporator Temperature Sensor (Ice Maker Evaporator Temperature Detection Means)
50 Refrigerant Cooling Circuit 51 Internal Heat Exchanger Cooler 52 Internal Heat Exchanger Temperature Sensor (Internal Heat Exchanger Temperature Detection Means)
54 Chilled water circuit 90 Control unit (control means)
91 Control unit (control means)
92 Control unit (control means)
93 Control unit (control means)
B Ice bank L Refrigerant pipeline W Cooling water

Claims (5)

A compressor that compresses the refrigerant, a radiator that dissipates the refrigerant supplied from the compressor in a supercritical pressure state, an expansion mechanism that squeezes and expands the refrigerant supplied from the radiator, and a supply from the expansion mechanism An evaporator for evaporating the refrigerant to be returned to the compressor, and a refrigerant cooling circuit comprising:
The ice-making and chilled water refrigerant valves that allow the refrigerant to flow in and out of the ice-making evaporator and the chilled water evaporator, which are connected in parallel in a manner that allows the ice maker and the cooling water tank to be independently cooled, and the internal temperature of the refrigerator are measured. An internal temperature detecting means for outputting a temperature signal, an ice making refrigerant inlet pipe temperature detecting means for measuring a refrigerant inlet pipe temperature of the ice making evaporator and outputting a temperature signal, the ice making refrigerant valve and the cold water refrigerant valve. Control means for controlling opening and closing,
When the ice making machine is started, the control means controls opening and closing of the ice making refrigerant valve and the cold water refrigerant valve based on temperature signals output from the internal temperature detecting means and the ice making refrigerant inlet pipe temperature detecting means. And the refrigerant | coolant cooling circuit characterized by cooling the refrigerant | coolant supplied to the said ice-making evaporator with the low-temperature refrigerant | coolant which has stayed in the said cold water evaporator.   The refrigerant cooling circuit according to claim 1, wherein a refrigerant outlet pipe of the cold water evaporator is provided with a cold water refrigerant outlet valve, and the refrigerant is stored in the cold water evaporator.   An ice making evaporator cooler for cooling the ice making evaporator; and an ice making evaporator temperature detecting means for measuring a temperature of a refrigerant pipe of the ice making evaporator and outputting a temperature signal. The ice making evaporator temperature detecting means outputs 2. The refrigerant cooling circuit according to claim 1, wherein cooling water stored in the cooling water tank is supplied to the ice making evaporator cooler based on a temperature signal to cool the ice making evaporator.   The cooling water stored in the cooling water tank is sent around the refrigerant pipe that communicates the compressor and the expansion mechanism to cool the refrigerant flowing through the refrigerant pipe. The refrigerant cooling circuit according to 1.   The refrigerant cooling circuit according to claim 1, wherein the refrigerant is carbon dioxide.

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