JP2006125789A - Cooling device and vending machine equipped with the same - Google Patents

Abstract

A cooling device capable of executing a stable refrigeration cycle without using a refrigerant amount adjusting means when a refrigerant is in a supercritical pressure state on a high pressure side of a refrigerant cooling circuit, and a vending machine using the device I will provide a.
A compressor that compresses a refrigerant, a heat radiating means that radiates the refrigerant, a throttle means that adjusts the flow rate of the refrigerant, an evaporation means that has a plurality of evaporators that evaporate the refrigerant and return it to the compressor; In a refrigerant cooling circuit having a critical pressure detecting means for detecting the critical pressure of the refrigerant flowing in the heat radiating means, operation is performed by selectively flowing the refrigerant into a plurality of evaporators of the evaporating means according to the detection result of the critical pressure detecting means. Control. When the pressure of the radiator on the high-pressure side exceeds the critical pressure, the refrigerant volume is expanded by flowing the refrigerant to the auxiliary evaporator, the refrigerant volume on the high-pressure side is reduced, and the pressure rise can be suppressed. Machine stoppage and damage can be avoided, and the heat transfer area of the operating evaporator increases, so the cooling capacity can be maintained at a high level.
[Selection] Figure 3

Description

  The present invention relates to a cooling device for a vending machine that cools and heats a product such as a beverage contained in a container such as a can, a bottle, a pack, or a plastic bottle for sale.

  A refrigerant cooling circuit for cooling the inside of a heat-insulating housing (for example, inside a vending machine) combines a compressor, a radiator, a throttle, and an evaporator to form a refrigerant circulation path, and a series of refrigeration A refrigerant is circulated by executing a cycle. As the refrigerant circulating in the refrigerant cooling circuit, HF C refrigerant (hydrofluorocarbon) is generally used today. However, from the viewpoint of protecting the global environment, there is a demand for the development of a refrigerant that has less influence on the global environment. Therefore, recently, the development of a refrigerant cooling circuit that uses carbon dioxide as a refrigerant that does not adversely affect the human body in terms of nonflammability, safety, noncorrosiveness, and less impact on the ozone layer has been promoted. Yes.

  By the way, when carbon dioxide is used as the refrigerant in the refrigerant cooling circuit, the critical temperature of carbon dioxide is as low as about 31 ° C. May cause pressure conditions. In this case, the pressure on the high-pressure side of the refrigerant cooling circuit (the refrigerant circulation path from the compressor output part to the input part of the throttle part) becomes high, and the low-pressure side of the refrigerant cooling circuit (from the output part of the throttle part to the input of the compressor) The amount of refrigerant in the refrigerant circulation path to the portion is reduced. That is, the compressor performs a low-efficiency overload operation, and further stops when the overload operation reaches a limit.

  Therefore, as a method for solving the above-described problem, a method in which refrigerant amount adjusting means such as an accumulator and a receiver is provided in the refrigerant circulation path is known (for example, Patent Document 1).

In addition, when an electronic expansion valve is provided in the refrigerant circulation path and the high pressure side is above the critical pressure, the valve circuit is opened to increase the pressure on the low pressure side and increase the amount of refrigerant in the low pressure side pipe to increase the pressure in the high pressure side pipe. There is also a method for reducing the volume of the refrigerant (for example, Patent Document 2).
Japanese National Patent Publication No. 7-502335 JP 2004-54424 A

  However, the conventional apparatus described in Patent Document 1 requires a dedicated space for disposing the refrigerant amount adjusting means, and thus there is a problem that cannot be handled by a small heat insulating casing. Further, since the refrigerant amount adjusting means is added, there is a problem that the product cost increases. Moreover, in the conventional apparatus described in Patent Document 2, since the temperature of the refrigerant rises when the pressure on the low pressure side is increased, the temperature difference between the internal air and the refrigerant becomes small, resulting in a problem that the cooling capacity is lowered.

  Therefore, the present invention provides a cooling device capable of executing a stable refrigeration cycle without using the above refrigerant amount adjusting means when the refrigerant is in a supercritical pressure state on the high pressure side of the refrigerant cooling circuit, and the cooling device The purpose is to provide a vending machine using the.

In order to achieve the above object, a cooling device according to claim 1 of the present invention is supplied from a compressor that compresses a refrigerant, heat radiating means that radiates the refrigerant supplied from the compressor, and the radiator. A throttle means for adjusting the flow rate of the refrigerant, an evaporation means having a plurality of evaporators for evaporating the refrigerant supplied from the throttle portion and returning it to the compressor, and detecting a critical pressure of the refrigerant flowing in the heat radiating means A cooling device having a critical pressure detecting means for
According to a detection result of the critical pressure detection means, there is provided control means for operating by selectively flowing a refrigerant into a plurality of evaporators of the evaporation means.

  A cooling device according to a second aspect of the present invention is the cooling device according to the first aspect, characterized in that the plurality of evaporators are evaporation means arranged in parallel or in series.

Moreover, the cooling device according to claim 3 of the present invention is supplied from the radiator, a compressor that compresses the refrigerant, a heat radiating unit that has a plurality of radiators that radiate the refrigerant supplied from the compressor, and the radiator. Throttle means for adjusting the flow rate of the refrigerant, evaporating means for evaporating the refrigerant supplied from the throttle portion and returning it to the compressor, and critical pressure detection means for detecting the critical pressure of the refrigerant flowing through the heat radiating means Having a cooling device,
According to the detection result of the critical pressure detection means, there is provided control means for operating by selectively flowing a refrigerant into a plurality of radiators of the heat dissipation means.

A cooling device according to a fourth aspect of the present invention is the cooling device according to the third aspect, characterized in that the plurality of heat radiators are heat radiation means arranged in parallel or in series.
The cooling device according to claim 5 of the present invention is supplied from the radiator, a compressor that compresses the refrigerant, a heat radiating unit that has a plurality of radiators that radiate the refrigerant supplied from the compressor, and the radiator. A throttle means for adjusting the flow rate of the refrigerant, an evaporation means having a plurality of evaporators for evaporating the refrigerant supplied from the throttle portion and returning it to the compressor, and detecting a critical pressure of the refrigerant flowing in the heat radiating means In a cooling device having a critical pressure detection means,
According to a detection result of the critical pressure detection means, a plurality of evaporators of the evaporation means, and a control means for operating by selectively flowing a refrigerant into the plurality of radiators of the heat dissipation means are provided. And

  According to a sixth aspect of the present invention, there is provided a vending machine comprising the cooling device according to any one of the first to fifth aspects.

  According to the cooling device according to claims 1 and 2 of the present invention, when the pressure of the radiator on the high pressure side exceeds the critical pressure, the piping volume on the low pressure side is expanded by flowing the refrigerant through the auxiliary evaporator. As a result of reducing the volume of the refrigerant on the high-pressure side and suppressing the pressure rise, the stoppage and damage of the compressor can be avoided, and the heat transfer area of the operating evaporator increases, so that the cooling capacity can be maintained at a high level.

  According to the cooling device according to claims 3 and 4 of the present invention, when the pressure of the high-pressure side radiator exceeds the critical pressure, the high-pressure side pipe volume is increased by flowing the refrigerant through the plurality of radiators. As a result, the rise in the pressure in the radiator can be suppressed, so that the refrigerant in the radiator does not exceed the critical point, the compressor can be stopped and damaged, and the transmission of the operating evaporator can be avoided. Since the heat area increases, the cooling capacity can be maintained at a high level.

  Further, according to the cooling device according to claim 5 of the present invention, when the pressure of the radiator on the high-pressure side exceeds the critical pressure, the refrigerant is selectively supplied to the plurality of evaporators and the plurality of radiators. Since the pipe volume on the low-pressure side and high-pressure side is increased, the refrigerant volume on the high-pressure side is reduced and the pressure rise can be suppressed. As a result, the compressor can be stably operated more precisely, and the compressor can be stopped and damaged. In addition, since the heat transfer area of the operating evaporator increases, the cooling capacity can be maintained at a high level.

  Further, according to the vending machine according to claim 6 of the present invention, since the cooling device is provided, the cooling device can be operated so that the pressure of the radiator on the high pressure side does not exceed the critical pressure. Cooling operation can be performed stably even when is high.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. Note that the present invention is not limited to the embodiments.

  (Embodiment 1) FIGS. 1 to 4 are explanatory views of Example 1 schematically showing the form of the cooling device according to the first aspect of the present invention. 1 is a front view of a vending machine equipped with a cooling device, FIG. 2 is a cross-sectional view of the vending machine, FIG. 3 is a refrigerant circuit of the cooling device, and FIG. 4 is a control block diagram of the vending machine. In the following, for convenience of explanation, the cooling device will be described as being applied to a vending machine.

  1 and 2, the vending machine includes a main body cabinet 1. The main body cabinet 1 is formed as a rectangular heat insulator having an open front surface. The main body cabinet 1 is provided with an outer door 2 and inner doors 3a and 3b on the front surface thereof, and three independent commodity containers 5a partitioned by, for example, two heat insulating partition plates 4a and 4b. 5b and 5c are provided in a side-by-side manner. More specifically, the outer door 2 is for opening and closing the front opening of the main body cabinet 1, and the inner doors 3a and 3b are for opening and closing the front surfaces of the product containers 5a, 5b and 5c. is there. The inner doors 3a and 3b are divided into upper and lower parts, and the upper door 3a opens and closes when a product is replenished. The product storage 5a, 5b, 5c is for storing the product W such as a canned beverage or a beverage containing a plastic bottle while maintaining the desired temperature, and the capacity of the storage is 5a, 5c, 5b. It is small in order of.

  The product storage 5a, 5b, 5c is provided with a product storage rack 6, a carry-out mechanism 7 and a product carry-out shooter 8, respectively. The product storage rack 6 is for storing the products W in a manner of being arranged along the vertical direction. The carry-out mechanism 7 is provided at the lower part of the product storage rack 6, and is used to carry out the products W at the bottom of the product group stored in the product storage rack 6 one by one. The product carry-out shooter 8 is for guiding the product W carried out from the carry-out mechanism 7 on the surface thereof to the product take-out port 3c, and a large number of holes are formed in the surface to allow the cooling and heating air to pass therethrough. It is like that.

  A cooling device 10 is disposed in the machine room 9 inside the main body cabinet 1 and outside the commodity storage 5a, 5b, 5c.

  FIG. 3 is a conceptual diagram conceptually showing the cooling device (cooling device according to the embodiment of the present invention) shown in FIGS. 1 and 2. In FIG. 1, the cooling device 10 includes a compressor 20, a heat radiating unit 30, an electronic expansion valve 40, and evaporation units 500a, 50b, and 50c (hereinafter also simply referred to as an evaporation unit 50). . In this cooling device 10, as a refrigerant, carbon dioxide is used which has non-flammability, safety and non-corrosion properties and has little influence on the ozone layer.

  The compressor 20 compresses the refrigerant (carbon dioxide) from the evaporation unit 50 to a high temperature and high pressure state. The compressor 20 is a two-stage compressor that performs a compression operation in two steps. More specifically, the compressor 20 includes a first compressor 21 that performs a first (first) compression operation and a second compressor 22 that performs a second (last) compression operation. An intermediate heat exchanger 23 is provided between them. The intermediate heat exchanger 23 cools the refrigerant compressed by the first compression operation by the first compressor 21, that is, releases the heat to return the refrigerant to the second compressor 22.

  Thus, the compressor 20 can compress the refrigerant to a desired high temperature and high pressure state with low power consumption by executing the compression operation twice through the intermediate heat exchanger 23. In the present embodiment, the refrigerant is compressed to about 4.9 MPa by the first compression by the first compressor 21, and the refrigerant is compressed to about 9.8 MPa by the second compression by the second compressor 22. To do.

  An oil separator 24 is connected to the compressor 20. The oil separator 24 is for returning the refrigeration oil sent from the compressor 20 (second compressor 22) to the compressor 20 (first compressor 21). The refrigerating machine oil prevents friction and refrigerant leakage inside the compressor 20, but it is difficult to completely seal the refrigerating machine oil inside the compressor 20. In particular, as described above, the compressor 20 compresses the refrigerant to a high pressure, and this pressure is much higher than when a conventional refrigerant (for example, HFC (hydrofluorocarbon)) is used. The amount of refrigeration oil delivered from 20 increases. Therefore, in the present embodiment, an oil separator 24 is connected between the outlet side of the second compressor 22 and the inlet side of the first compressor 21, and the refrigerating machine oil sent from the second compressor 22 is supplied. The first compressor 21 is returned. Reference numeral 25 in FIG. 3 is a capillary tube for reducing the pressure of the refrigerating machine oil and the refrigerant returning to the compressor 20.

  Here, as the compressor 20, a reciprocating compressor, a rotary compressor, a scroll compressor, or an inverter compressor capable of adjusting the compression capacity thereof can be applied. Then, a compressor corresponding to the object, environment, or cost required for the entire apparatus in which the cooling device 10 is disposed may be appropriately applied.

  The heat dissipation unit 30 liquefies the refrigerant by radiating heat from the refrigerant compressed to a high temperature and high pressure state by the compressor 20. The heat dissipation unit 30 in the present embodiment uses a fin tube type composed of copper tubes and aluminum fins. In addition, a radiator temperature sensor 110 as a critical pressure detecting means is installed at the inlet of the heat radiating unit 30 to monitor the critical pressure of the heat radiating unit 30 and detects the critical pressure of the heat radiating unit 30 as the critical temperature of the refrigerant. To do. The electronic expansion valve 40 adiabatically expands the refrigerant radiated by the heat radiating unit 30, that is, adjusts the refrigerant to a low temperature and low pressure state by reducing the pressure. The critical pressure detecting means may be a pressure sensor.

  The evaporation unit 50 evaporates the refrigerant adiabatically expanded to a low temperature and low pressure state by the electronic expansion valve 40. As the refrigerant evaporates, the area around the evaporation unit 50 is deprived of heat and cooled.

  As shown in FIG. 2, the evaporation unit 50 is disposed inside each of the product storage units 5 a, 5 b, 5 c in order to cool the plurality of product storage units 5 a, 5 b, 5 c independently of each other. is there. That is, the evaporation units 500a, 50b, and 50c are connected to respective paths branched from the electronic expansion valve 40 in three directions. Furthermore, the evaporator unit 500a has an evaporator 51a and an auxiliary evaporator 53a connected in parallel, and the auxiliary evaporator 53a has a smaller capacity than the evaporator 51a.

  In addition, solenoid valves 52a, 54a, 52b, and 52c are provided in the respective paths. By selectively opening the solenoid valves 52a, 54a, 52b, and 52c, the corresponding evaporation units 500a, 50b, and 50c are provided. The refrigerant from the electronic expansion valve 40 is sent out. On the other hand, the paths on the outlet side of the respective evaporation units 500a, 50b, 50c are gathered together and connected to the first compressor 21 of the compressor 20.

  In the vicinity of the evaporation units 50a, 50b, and 50c in each of the commodity containers 5a, 5b, and 5c, a heater H, an internal fan F, a circulation duct D, and the like are provided. The heater H is for heating the air (internal atmosphere) of the product storage 5a, 5b, 5c, that is, for heating the product W stored in the product storage rack 6. The internal blower fan F blows the air cooled by the evaporation unit 50 (cold air) or the air heated by the heater H (warm air), thereby generating cold heat from the evaporation unit 50 or high heat from the heater H. Heat is transferred to the product W. The air blown by the internal blower fan F is circulated through the circulation duct D. Moreover, the code | symbol 71 in FIG. 2 is a fan cover which covers the ventilation fan F in a store | warehouse | chamber, and the code | symbol 72 is a temperature sensor which detects the temperature in goods storage 5a, 5b, 5c.

  A refrigerant circulation path L for circulating the refrigerant is formed by the compressor 20, the heat radiating unit 30, the electronic expansion valve 40 and the evaporation unit 50, the path connecting them, and the like. The refrigerant circulation path L is provided with an internal heat exchanger 60. The internal heat exchanger 60 exchanges heat between the high-pressure refrigerant from the heat radiating unit 30 and the low-pressure refrigerant from the evaporation unit 50. More specifically, inside the internal heat exchanger 60, a refrigerant pipe 61 through which the refrigerant radiated by the heat radiating unit 30 flows and a refrigerant pipe 62 through which the refrigerant evaporated by the evaporation unit 50 flows are mutually connected. They are arranged in a non-contact countercurrent manner with a heat exchangeable distance.

  FIG. 4 is a diagram showing a control block of the vending machine. The control device 100 detects the internal temperature by the cooling heating operation mode of the product storage 5a, 5b, 5c, controls the operation of the cooling device 10 and the heater H, and selects the product in the product storage as desired. It is for setting to temperature.

  The control device 100 will be described in more detail. The operation mode selection switch 105 for setting the cooling or heating mode of the product storage 5a, 5b, 5c, the radiator temperature sensor 110 for detecting the inlet temperature of the radiator 31, the product The internal temperature sensor 72 for detecting the internal temperature of the storage 5a, 5b, 5c is input, and the compressor 20 and the heater H are started and stopped, and the electromagnetic valves 52 and 54 are opened and closed.

  The cooling device 10 having the above-described configuration can cool the internal atmosphere of the commodity storage 5a, 5b, 5c of the vending machine as follows. Here, the operation | movement is demonstrated as what cools only the internal atmosphere of the goods storage 5a.

  When only the internal atmosphere of the product storage 5a is cooled, it is not necessary to circulate the refrigerant in the evaporation units 50b and 50c disposed in the other product storages 5b and 5c. Therefore, only the solenoid valve 52a is opened, and the other solenoid valves 54a, 51b, 51c are closed. Moreover, the heater H arrange | positioned inside the goods storage 5a is an OFF state.

  The refrigerant in the refrigerant circuit L is compressed in two by the compressor 20. More specifically, the refrigerant is compressed (compressed to about 4.9 MPa) by the first compressor 21 and then sent to the intermediate heat exchanger 23. The refrigerant sent to the intermediate heat exchanger 23 is cooled by releasing heat in the intermediate heat exchanger 23. The refrigerant cooled by the intermediate heat exchanger 23 is sent again to the second compressor 22 and is compressed (compressed to about 9.8 MPa) by the second compressor 22 to be in a high temperature and high pressure state. In this case, the refrigeration oil sent together with the refrigerant from the second compressor 22 returns to the inlet side of the first compressor 21 by the oil separator 24.

  The high-temperature and high-pressure refrigerant is sent to the radiator 31 and is radiated and cooled by the radiator 31. The refrigerant cooled by the radiator 31 is sent to the electronic expansion valve 40 through the internal heat exchanger 60, and is decompressed and adiabatically expanded by the electronic expansion valve 40 to be in a low temperature and low pressure state.

  The low-temperature and low-pressure refrigerant is sent to the evaporator 51a through the open solenoid valve 52a. The refrigerant sent to the evaporator 51a evaporates by being given heat from the peripheral area of the evaporator 51a. In other words, the peripheral area of the evaporator 51a is cooled by taking heat away as the refrigerant evaporates to generate cold air. The generated cold air is blown out as shown by the arrow in FIG. 2 by the action of the internal blower fan F, whereby the internal atmosphere of the product storage case 5a is cooled. When the internal atmosphere of the product storage 5a is thus cooled, the product W stored in the product storage rack 6 disposed in the product storage 5a is in a desired temperature state (for example, about 5 ° C. ) Will be cooled.

  The refrigerant evaporated in the evaporation unit 500a is sent to the compressor 20 (first compressor 21) through the internal heat exchanger 60, compressed by the compressor 20, and the above cycle is repeated.

  In such an operating state of the cooling device 10, the temperature of the radiator temperature sensor 110 exceeds the critical temperature of the refrigerant, for example, when the outside air temperature is high. At this time, the control device 100 opens the electromagnetic valve 54a.

  By flowing the refrigerant through the auxiliary evaporator 53a, the pipe volume on the low pressure side is expanded, so that the refrigerant volume on the high pressure side is reduced and the pressure rise can be suppressed. As a result, stoppage and damage of the compressor can be avoided. I can do it. Further, by increasing the opening of the electronic expansion valve 40 so as to increase the amount of refrigerant on the low pressure side, even if the pressure on the low pressure side decreases and the evaporation temperature rises, the heat transfer area is equivalent to that of the auxiliary evaporator 53a. As a result of only increasing the heat transfer area, the heat exchange capacity is maintained in a high state.

  Moreover, if the temperature of the radiator temperature sensor 110 falls below a predetermined temperature (for example, 25 ° C.) lower than the critical temperature, the control device 100 closes the electromagnetic valve 54a. As a result, the refrigerant circulation rate is prevented from excessively decreasing, so that a high cooling capacity can be maintained.

  FIG. 5 is a refrigerant circuit diagram showing another embodiment 2 relating to the cooling device of the present invention according to claims 1 and 2. In the cooling device 10a shown in the figure, the difference from the first embodiment is a configuration in which two evaporators are connected in series to the evaporation unit 500a of the cooling device 10a, and other configurations are the same as those in the first embodiment. . More specifically, the evaporation unit 500a is connected in series with the solenoid valve 52a, the evaporator 51a, the solenoid valve 55a, and the auxiliary evaporator 53a, and is bypassed between the evaporator 51a and the solenoid valve 55a via the solenoid valve 56a. It is the structure which connected the circuit.

  In such a configuration, when only the product storage 5a is cooled, the electromagnetic valves 52a and 56a are opened, and the electromagnetic valve 55a is closed. Since the operation of the refrigerant circuit in this state is the same as that of the first embodiment, the description thereof is omitted.

  In such an operating state of the cooling device 10a, when the temperature of the radiator temperature sensor 110 exceeds the critical temperature, the control device 100 opens the electromagnetic valve 55a and closes the electromagnetic valve 56a.

  By flowing the refrigerant through the auxiliary evaporator 53a, the pipe volume on the low pressure side is expanded, so that the pressure increase on the high pressure side can be suppressed for the same reason as in the first embodiment.

  FIG. 6 is a refrigerant circuit diagram showing another embodiment 3 to which the embodiment 1 is applied. In the cooling device 10b of the same figure, the difference from the first embodiment is a configuration in which one evaporator 51 and one auxiliary evaporator 53 are connected in parallel to each commodity storage 5, and the other configurations are the embodiments. 1 is the same.

  When the cooling and heating operation mode is set to cold operation for only one room, the operation is the same as that of the first embodiment. Therefore, here, the case of the operation mode in which the three rooms perform cold operation will be described.

  When a three-room cold operation signal is input from the operation mode selection switch 105, the control device 100 opens the electromagnetic valves 52a, 52b, and 52c and closes the electromagnetic valves 54a, 54b, and 54c.

  In the operation state of the cooling device 10b, when the temperature of the radiator temperature sensor 110 exceeds the critical temperature, the control device 100 opens the electromagnetic valves 54 in descending order of the product storage. More specifically, the control device 100 opens the solenoid valves 54a, 54c, 54b in this order while detecting the temperature of the sensor 110.

  Further, when the temperature of the radiator temperature sensor 110 becomes a critical temperature or lower (for example, 25 ° C.), the control device 100 opens the electromagnetic valve 54 in the reverse order.

  Since there are three auxiliary evaporators 53 in this way, the piping volume on the low pressure side can be expanded in three stages, so finer control is possible compared to the first embodiment.

  The opening order of the electromagnetic valves 54 may be performed in ascending order of the auxiliary evaporator 53.

  (Embodiment 2) FIGS. 7 and 8 are explanatory views of Embodiment 4 schematically showing the form of the cooling device according to the third and fourth aspects of the present invention. FIG. 7 shows a refrigerant circuit diagram, and FIG. 8 shows a control block diagram. The differences from the first embodiment are a heat dissipation unit 300, an evaporation unit 50 a, and a control device 101. More specifically, in the heat radiating unit 300, the auxiliary radiator 33 in which the electromagnetic valve 35 is connected in series between the outlet of the second-stage compressor 22 and the internal heat exchanger 61 is connected in parallel with the radiator 31. It is a configuration to connect. Further, the evaporation unit 50a has no auxiliary evaporator and is configured by an evaporator 51a and an electromagnetic valve 52a, and the control device 101 has a configuration in which an electromagnetic valve 35 related to the auxiliary radiator 33 is newly added on the output side. Other configurations are the same as those of the first embodiment.

  In this configuration, the operation mode of the cooling device 10c will be described in the operation mode in which only the product storage 5a is cooled. The operation is the same in other operation modes.

  During the initial operation, the solenoid valve 52a is in the open state and the solenoid valves 35, 52b, and 52c are in the closed state.

  When the temperature of the radiator temperature sensor 110 rises and reaches a temperature exceeding the critical pressure of the refrigerant, the control circuit 101 opens the electromagnetic valve 33 for the auxiliary radiator. Then, the refrigerant flowing out from the second-stage compressor 22 is divided into the radiator 31 and the auxiliary radiator 33, merges after the outlet of each radiator, and flows to the intermediate heat exchanger 61.

  Since the refrigerant flows into the radiator 31 and the auxiliary radiator 33, the high-pressure side pipe volume is increased, and therefore, it is possible to suppress an increase in the pressure in the radiator. As a result, the refrigerant in the radiator does not exceed the critical point, and the cooling operation can be stably continued without stopping or damaging the compressor.

  When the temperature of the radiator temperature sensor 110 decreases and reaches a stable point (for example, 25 ° C.), the control circuit 101 closes the electromagnetic valve 35 for the auxiliary radiator. As a result, the pipe volume in the heat dissipation unit 300 is reduced and the amount of liquid refrigerant retained is reduced, so that the reduction in the amount of refrigerant circulating in the refrigerant circuit is suppressed, and the cooling capacity is maintained in a high state.

  FIG. 9 is a refrigerant circuit diagram showing another embodiment 5 relating to the cooling device of the present invention according to claims 3 and 4. In the cooling device 10d shown in the figure, the difference from the fourth embodiment is a configuration in which the radiator 31 of the heat radiating unit 310 and the auxiliary radiator 32 are connected in series, and other configurations are the same as those of the fourth embodiment. More specifically, in the heat radiating unit 30, the radiator 31 and the auxiliary radiator 33 are connected in series via the electromagnetic valve 35, and the electromagnetic valve 36 is connected between the outlet of the radiator 31 and the outlet of the auxiliary radiator 33. It is the structure which connected the bypass circuit via.

  In such a configuration, when only the product storage 5a is cooled, the electromagnetic valves 36 and 52a are opened, and the electromagnetic valves 35, 52b and 52c are closed. The refrigerant flow at this time is the same as that of the fourth embodiment, and the description thereof is omitted.

  When the temperature of the radiator temperature sensor 110 exceeds the critical temperature, the control device 101 opens the electromagnetic valve 35 and closes the electromagnetic valve 36. As a result, the high-pressure side pipe volume is increased as in the operation of the fourth embodiment, so that the pressure in the radiator can be suppressed and a stable cooling operation can be maintained.

  FIG. 10 is a refrigerant circuit diagram showing another embodiment 6 relating to the cooling device of the present invention according to claim 5. The cooling device 10e shown in the figure has a configuration in which the radiator unit 300 of the fourth embodiment is combined with the cooling device 10 of the first embodiment, and the other points are the same as those of the first embodiment.

  In such a configuration, when only the commodity storage 5a is cooled, the electromagnetic valve 52a is opened and the electromagnetic valves 35, 54a, 52b, and 52c are closed. The refrigerant flow at this time is the same as that in the first embodiment, and a description thereof will be omitted.

  When the temperature of the radiator temperature sensor 110 exceeds the critical temperature, the control device 101 opens the electromagnetic valve 54a. As a result, the low-pressure side pipe volume is increased in the same manner as in the operation of the first embodiment, so that the pressure in the heat dissipation unit can be suppressed and a stable cooling operation can be maintained. If the temperature of the radiator temperature sensor 110 still exceeds the critical temperature, the electromagnetic valve 35 is opened. As a result, the high-pressure side pipe volume is increased as in the operation of the fourth embodiment, so that the pressure in the heat radiating unit can be suppressed and a stable cooling operation can be maintained.

  Since the auxiliary evaporator 53a and the auxiliary radiator 33 are provided as described above, the pressure in the heat radiating unit can be suppressed in two stages, so that finer control is possible compared to the first embodiment.

  The opening order of the solenoid valves may be that the solenoid valve 54a is opened after the solenoid valve 35 is opened.

  Further, according to the vending machine according to the embodiment of the present invention, since the cooling device is provided and the flow of the refrigerant is controlled by the control device, the refrigeration capacity and the operation efficiency are improved and the compressor is improved. Can prevent damage.

  As described above, the present invention is useful, for example, as a cooling device and a vending machine for cooling the internal atmosphere of a heat insulating housing.

It is front sectional drawing which showed typically the vending machine which concerns on embodiment of this invention. 1 is a cross-sectional side view schematically showing a vending machine according to an embodiment of the present invention. It is the refrigerant circuit figure which showed notionally the cooling device of Example 1 of this invention. It is a control block diagram of the vending machine which concerns on Embodiment 1 of this invention. It is the refrigerant circuit figure which showed notionally the cooling device of Example 2 of this invention. It is the refrigerant circuit figure which showed notionally the cooling device of Example 3 of this invention. It is the refrigerant circuit figure which showed notionally the cooling device of Example 4 which concerns on Embodiment 2 of this invention. It is a control block diagram of the vending machine which concerns on Embodiment 2 of this invention. It is the refrigerant circuit figure which showed notionally the cooling device of Example 5 of this invention. It is the refrigerant circuit figure which showed notionally the cooling device of Example 6 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Cooling device 20 Compressor 21 1st compressor 22 2nd compressor 23 Intermediate heat exchanger 30 Radiation unit 31 Radiator 33 Auxiliary radiator 34 Solenoid valve 35 Solenoid valve 40 Electronic expansion valve 50 Evaporating unit 51 Evaporator 52 Solenoid valve 53 Auxiliary evaporator 54 Solenoid valve 60 Internal heat exchanger 100 Controller 110 Radiator temperature sensor

Claims (6)

A compressor for compressing the refrigerant; heat radiating means for dissipating the refrigerant supplied from the compressor; throttle means for adjusting a flow rate of the refrigerant supplied from the radiator; and evaporating the refrigerant supplied from the throttle unit In a cooling device having an evaporation means having a plurality of evaporators to be returned to the compressor, and a critical pressure detection means for detecting a critical pressure of the refrigerant flowing in the heat dissipation means,
A cooling and heating apparatus, comprising: a control unit that operates by selectively causing a refrigerant to flow into a plurality of evaporators of the evaporation unit according to a detection result of the critical pressure detection unit.   The cooling device according to claim 1, wherein the plurality of evaporators are evaporation means arranged in parallel or in series. A compressor for compressing the refrigerant, a heat radiating means having a plurality of radiators for radiating the refrigerant supplied from the compressor, a throttle means for adjusting the flow rate of the refrigerant supplied from the radiator, and the throttle unit In a cooling device having evaporation means for evaporating supplied refrigerant and returning it to the compressor, and critical pressure detection means for detecting a critical pressure of the refrigerant flowing in the heat dissipation means,
A cooling device comprising control means for operating by selectively injecting refrigerant into a plurality of radiators of the heat radiating means according to a detection result of the critical pressure detecting means.   The cooling device according to claim 3, wherein the plurality of heat radiators are heat radiation means arranged in parallel or in series. A compressor for compressing the refrigerant, a heat radiating means having a plurality of radiators for radiating the refrigerant supplied from the compressor, a throttle means for adjusting the flow rate of the refrigerant supplied from the radiator, and the throttle unit In a cooling device having evaporation means having a plurality of evaporators for evaporating supplied refrigerant and returning it to the compressor, and critical pressure detection means for detecting a critical pressure of the refrigerant flowing in the heat dissipation means,
According to a detection result of the critical pressure detection means, a plurality of evaporators of the evaporation means, and a control means for operating by selectively flowing a refrigerant into the plurality of radiators of the heat dissipation means are provided. And cooling device.   A vending machine comprising the cooling device according to any one of claims 1 to 5.

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