CN1715810A - Cooling and heating systems, refrigerators and vending machines using the systems - Google Patents

Abstract

The present invention relates to a cooling system for cooling and heating using latent heat generated when refrigerant compressed by a compressor is condensed, a refrigerator using the system, and a vending machine for heating or cooling products such as canned drinks. The present invention uses multiple pipes connected in parallel to connect the expansion mechanism and the outdoor heat exchanger together. And, when cooling the storage chamber, the refrigerant is made to flow through the pipe in which the drier is installed in the passage. When heating the storage chamber, the refrigerant flows through the pipes other than the pipes in which the drier is installed in the passage. Alternatively, in the case of a common compressor, a three-way valve is used to switch between a cooling system with a drier in the passage that cools the storage chamber and a heating system that does not provide a dryer in the passage and heats the storage chamber.

Description

Cooling and heating systems, refrigerators and vending machines using the systems

technical field

The present invention relates to a cooling system for cooling and heating using latent heat generated when refrigerant compressed by a compressor is condensed, a refrigerator using the system, and a vending machine for heating or cooling products such as canned drinks.

Background technique

In recent years, there has been an increasing demand for reduction in power consumption of refrigeration and heat storage equipment such as product showcases. For this reason, in order to reduce power consumption when heating with a heater, a technology has been proposed that switches the cooling system to a heat pump for heating in the same manner as in heating and cooling air conditioners. However, under refrigerated or frozen conditions such as product display cases, especially when the evaporating temperature is low, the water in the refrigerant freezes, which may clog the piping passage. Therefore, it is necessary to bring a desiccant composed of synthetic zeolite or the like into contact with the liquid refrigerant in the system to absorb and remove moisture in the refrigerant. The reason why the desiccant is in contact with the liquid refrigerant is that when the desiccant is in contact with the refrigerant effectively, if the desiccant is in contact with the gas refrigerant with a fast flow rate, the granulated synthetic zeolite particles are vibrated Contact and crush, so to prevent such particles from crushing. In addition, when using a natural refrigerant with a low global warming effect, that is, a hydrocarbon refrigerant, this point is even more important because the amount of water saturation is small.

In the past, people have also proposed such a structural scheme: a drier is installed in the pipeline passage connecting the indoor heat exchanger and the outdoor heat exchanger, and at the same time, the expansion mechanism is used respectively under cooling and heating, so that the liquid refrigerant is always in contact with the heat exchanger. desiccant contact. Such a structure is disclosed in, for example, Japanese Patent Application Laid-Open No. 11-304303. Next, a conventional cooling and heating system will be described with reference to the drawings.

Fig. 13 is a refrigerant circuit diagram of a conventional cooling and heating system. A conventional cooling and heating switching system basically consists of a compressor 81 , a four-way valve 82 , an accumulator 83 , an outdoor heat exchanger (hereinafter referred to as an exchanger) 84 , and an indoor heat exchanger (hereinafter referred to as an exchanger) 85 . In the cooling room, the flow path is set by the four-way valve 82 so that the refrigerant discharged from the compressor 81 is supplied to the exchanger 85 from the exchanger 84 . In this case, the refrigerant flows back from the accumulator 83 to the compressor 81 through the four-way valve 82 again. In the case of indoor heating, the four-way valve 82 is used to switch the flow path, so that the refrigerant discharged from the compressor 81 is supplied to the exchanger 84 by the exchanger 85, passes through the four-way valve 82 again, and flows from the accumulator 83 to the compressor 81. reflow.

In general, the exchanger 85 is installed in a heat-insulating space (not shown, hereinafter referred to as a storage room) that accommodates objects to be cooled and heated, such as canned beverages. On the other hand, the compressor 81, the four-way valve 82, the accumulator 83, and the exchanger 84 are arranged outside the storage chamber. In addition, the compressor 81 and the exchangers 84 and 85 are respectively blown by an independent blower fan (not shown) as required to promote air cooling and heat exchange.

On the pipe connecting the exchanger 84 and the exchanger 85, there are connected a heating capillary (hereinafter referred to as capillary) 86, a cooling check valve (hereinafter referred to as valve) 87, a cooling capillary (hereinafter referred to as capillary) 88, and a heating check valve (hereinafter referred to as capillary). Return valve (hereinafter referred to as valve) 89 and dryer 90. The capillary 86 and the valve 87, and the capillary 88 and the valve 89 are respectively connected in parallel. In addition, a dryer 90 is connected to a position where the capillary 86 and the capillary 88 are sandwiched.

Next, the operation of the conventional cooling and heating switching system configured as above will be described. When cooling the storage chamber, the refrigerant discharged from the compressor 81 is supplied to the exchanger 84 by switching the flow path of the four-way valve 82 to be condensed and liquefied. Liquid refrigerant discharged from exchanger 84 is supplied to dryer 90 through valve 87 . Then, the liquid refrigerant discharged from the drier 90 is decompressed through the capillary tube 88 , supplied to the exchanger 85 to be vaporized, and the gas refrigerant passes through the four-way valve 82 again and flows back from the accumulator 83 to the compressor 81 .

When heating the storage chamber, the refrigerant discharged from the compressor 81 switches its flow path by the four-way valve 82, is supplied to the exchanger 85, and is condensed and liquefied. The liquid refrigerant discharged from the exchanger 85 is supplied to the dryer 90 through the valve 89 . Then, the liquid refrigerant discharged from the dryer 90 is decompressed by the capillary 86 and supplied to the exchanger 84 for evaporation and vaporization, and the gas refrigerant passes through the four-way valve 82 again, and flows back from the accumulator 83 to the compressor 81 .

Then, a drier 90 is connected at the position sandwiched between the capillary tube 86 and the capillary tube 88 , and the liquid refrigerant is supplied to the drier 90 through the valves 87 and 89 respectively connected in parallel to the capillary tubes. With this structure, the refrigerant can be effectively brought into contact with the dryer 90 no matter when cooling or heating, and at the same time, the gas refrigerant with a fast flow rate can prevent the granulated synthetic zeolite particles from being damaged due to vibration contact. Smash things happen.

However, in the conventional configuration described above, when products such as canned beverages are heated to 50 to 100° C., the drier 90 comes into contact with the high-temperature liquid refrigerant. As a result, the water adsorption capacity of the synthetic zeolite is lowered, and as a result, the amount of water circulating in the system increases. Therefore, the deterioration of the insulating material inside the compressor 81 is promoted to reduce the durability of the compressor 81, and at the same time, the risk of clogging of the piping passage due to freezing of moisture in the capillary tube 86 increases. In particular, when the drier 90 is arranged in the storage chamber or near the exchanger 85 , a higher temperature liquid refrigerant close to the condensation temperature of the exchanger 85 flows into the drier 90 , causing more serious problems.

In addition, when the dryer 90 is arranged outside the housing or near the exchanger 84 and supercooled liquid refrigerant is supplied to the dryer 90 during heating, the distance from the exchanger 85 to the dryer 90 is increased. Accordingly, the stagnant amount of liquid refrigerant in the connecting pipe increases, and as a result, the amount of refrigerant necessary for heating increases. In particular, in the case of using a natural refrigerant with low global warming effect, that is, a hydrocarbon refrigerant, the danger of burning at the time of leakage increases.

Contents of the invention

In the cooling and heating system of the present invention, the expansion mechanism and the outdoor heat exchanger are connected by a plurality of parallel pipes. And, when cooling the storage room, the refrigerant is made to flow through the pipe in which the drier is installed in the passage. When heating the storage chamber, the refrigerant flows through pipes other than the pipes in which the drier is installed in the passage. Alternatively, in the cooling and heating system of the present invention, the cooling system and the heating system share the compressor, and a three-way valve is used to switch the cooling system and the heating system. The cooling system is provided with a dryer in the passage to cool and heat the storage chamber The system does not set a dryer in the passage, and heats the containing room. According to any of the above schemes, it is possible to prevent the dryer from becoming high temperature, especially in the case of heating products such as canned beverages to a high temperature of 50-100°C, it can suppress the release of adsorbed moisture and prevent the moisture concentration in the system. increase.

Description of drawings

Fig. 1 is a refrigerant circuit diagram showing a cooling and heating system according to Embodiment 1 of the present invention.

Fig. 2 is a control block diagram of the cooling and heating system shown in Fig. 1 .

Fig. 3 is a refrigerant circuit diagram of another cooling and heating system according to Embodiment 1 of the present invention.

Fig. 4 is a refrigerant circuit diagram of yet another cooling and heating system according to Embodiment 1 of the present invention.

Fig. 5 is a refrigerant circuit diagram of another cooling and heating system according to Embodiment 1 of the present invention.

Fig. 6 is a diagram showing the operating range of the cooling and heating system shown in Fig. 5 .

Fig. 7 is a refrigerant circuit diagram of the cooling and heating system according to Embodiment 2 of the present invention.

Fig. 8 is a control block diagram of the cooling and heating system shown in Fig. 7 .

Fig. 9 is a refrigerant circuit diagram of the cooling and heating system according to Embodiment 3 of the present invention.

Fig. 10 is a control block diagram of the cooling and heating system shown in Fig. 9 .

Fig. 11 is a perspective view of the outdoor heat exchanger of the cooling and heating system shown in Fig. 9 .

Fig. 12 is a schematic view of an automatic vending machine equipped with a refrigerator according to an embodiment of the present invention.

Fig. 13 is a refrigerant circuit diagram of a conventional cooling and heating system.

Detailed ways

Embodiments of the present invention will be described below with reference to the drawings. In addition, in each embodiment, the same reference numerals are assigned to the same components as those in the preceding embodiments, and detailed description thereof will be omitted.

Example 1

Fig. 1 is a refrigerant circuit diagram of a cooling and heating system according to Embodiment 1 of the present invention. The cooling and heating system of this embodiment basically consists of compressor 1, four-way valve (hereinafter referred to as valve) 2, accumulator 3, outdoor heat exchanger (hereinafter referred to as exchanger) 4, indoor heat exchanger (hereinafter referred to as exchanger) 5 and pipes connecting these in a ring. The refrigerator is composed of such a cooling and heating system and a storage chamber 6 in which an exchanger 5 is disposed. In other words, the accommodation chamber 6 is divided so that the exchanger 5 performs cooling or heating. When cooling the inside of the storage chamber 6 , the refrigerant discharged from the compressor 1 is supplied to the exchanger 5 from the exchanger 4 by switching the flow path through the valve 2 . Then, it flows back from the accumulator 3 to the compressor 1 through the valve 2 again. When heating the inside of the storage chamber 6 , the refrigerant discharged from the compressor 1 is supplied to the exchanger 4 from the exchanger 5 by switching the flow path through the valve 2 . Then, it flows back from the accumulator 3 to the compressor 1 through the valve 2 again. In other words, the valve 2 is a switching valve for selecting the pipeline flow path. The valve 2 is composed of a combination of a rotary valve and a stepping motor, or an electromagnetic valve.

Here, the exchanger 5 is installed in the storage chamber 6 that accommodates cooling and heating objects such as filled beverages, and the compressor 1 , the valve 2 , the accumulator 3 , and the exchanger 4 are arranged outside the storage chamber 6 . In addition, the compressor 1, the exchanger 4, and the exchanger 5 send air according to needs through independent fans 7, 8, and 9 respectively, so as to promote air cooling and heat exchange.

In addition, the exchanger 4 and the exchanger 5 are connected by two parallel pipelines. In one pipe, a heating capillary (hereinafter referred to as capillary) 10 and a heating two-way valve (hereinafter referred to as valve) 11 are connected in series. In the other pipe, a cooling capillary (hereinafter referred to as capillary) 12 , a cooling two-way valve (hereinafter referred to as valve) 13 and a drier 14 are connected in series.

In other words, the capillary tubes 10, 12 serving as expansion mechanisms are connected to the exchanger 4 through two parallel pipelines. The valves 11 and 13 are also composed of a combination of a rotary valve and a stepping motor, or a solenoid valve. The drier 14 is installed approximately vertically so that the connection port to the valve 13 faces upward and the connection port to the exchanger 4 faces downward.

Furthermore, both the valves 11 and 13 and the drier 14 are installed near the exchanger 4, and in particular, the distance between the capillary 10, which becomes low temperature when heated, and the exchanger 4 is designed to be the shortest. In addition, the distance between the capillaries 10, 12 and the exchanger 5 is also designed to be the shortest.

Fig. 2 is a control block diagram of the cooling and heating system shown in Fig. 1 . The instruction unit 15 accepts an input from a user to determine whether the exchanger 5 performs a cooling operation or a heating operation. The instruction unit 15 is constituted by a switch or the like. The control unit 16 switches the valves 2 , 11 , and 13 based on the input from the instruction unit 15 , and also detects the operating state of the compressor 1 . The detection unit 19 is arranged in the accommodation chamber 6 and is used for detecting the adjustment temperature of the exchanger 5 .

Next, the operation of the cooling/heating switching system of the present configuration with the above-mentioned configuration will be described. When cooling the inside of the storage chamber 6 , the control unit 16 opens the valve 13 , closes the valve 11 , and drives the compressor 1 . The refrigerant discharged from the compressor 1 is supplied to the exchanger 4 by switching the flow path through the valve 2, and is condensed and liquefied. The liquid refrigerant discharged from the exchanger 4 is supplied to the drier 14 . The temperature of the liquid refrigerant is 30 to 40° C. which is substantially the same as the condensation temperature of the exchanger 4 . At this time, while the refrigerant stays inside the drier 14 , the liquid refrigerant comes into contact with synthetic zeolite (not shown) installed inside the drier 14 to remove moisture from the liquid refrigerant.

Then, the liquid refrigerant discharged from the dryer 14 is depressurized by the capillary tube 12 through the valve 13 and then supplied to the exchanger 5 for evaporation and vaporization. The gas refrigerant passes through the valve 2 again and flows back from the accumulator 3 to the compressor 1 . Here, the evaporation temperature of the exchanger 5 greatly changes according to the set temperature of the storage chamber 6 . Generally, in the case of cooling and filling beverages, etc., the set temperature is 5 to 10°C, and the evaporation temperature of the exchanger 5 is -15 to -5°C.

Moreover, when heating the inside of the storage chamber 6, the control unit 16 closes the valve 13, opens the valve 11, and drives the compressor 1. The refrigerant discharged from the compressor 1 is supplied to the exchanger 5 by switching the flow path through the valve 2, and is condensed and liquefied. The temperature of the liquid refrigerant varies greatly depending on the set temperature of the storage chamber 6 . Generally, in the case of heating and filling beverages, etc., the set temperature is 50-60°C, and the condensation temperature of the exchanger 5 is 70-80°C. If the drier 14 is exposed to this temperature, the moisture adsorption capacity of the synthetic zeolite (not shown) provided inside will be reduced by about half, and the adsorbed moisture may be released.

The liquid refrigerant discharged from the exchanger 5 is immediately decompressed by the capillary 10, and then supplied to the exchanger 4 through the valve 11 for evaporation and vaporization, and the gas refrigerant passes through the valve 2 again, and flows back from the accumulator 3 to the compressor 1. At this time, almost no liquid refrigerant stays inside the drier 14 , but saturated gas refrigerant having a temperature substantially the same as the evaporation temperature of the exchanger 4 is filled. The evaporation temperature of the exchanger 4 is 5-15°C.

Then, during heating, when the temperature of the storage chamber 6 rises to a set value, the detection unit 19 detects it, and the control unit 16 stops the compressor 1 and switches to open the valve 13 and close the valve 11. At this time, while the liquid refrigerant slowly passes through the capillary tube 12 and the valve 13 from the high-temperature and high-pressure exchanger 5, and slowly cools to about the temperature of the outdoor air, it flows to the dryer 14 and the exchanger 4, and the system The internal pressure gradually reaches equilibrium. Next, when the liquid refrigerant passes through the inside of the drier 14, synthetic zeolite (not shown) provided inside the drier 14 contacts the liquid refrigerant to remove moisture from the liquid refrigerant.

Then, the expansion mechanism constituted by the capillary tubes 10, 12 and the exchanger 4 are connected together with parallel pipelines. Furthermore, the control unit 16 controls the valves 2 , 11 , and 13 , and when the inside of the storage chamber 6 is cooled, the refrigerant flows through one pipe in which the dryer 14 is provided in the passage. On the other hand, when the interior of the storage chamber 6 is heated, the refrigerant flows through a pipe other than the pipe in which the drier 14 is provided in the passage. The control unit 16 then switches the operating state of the exchanger 5 . With such a structure, especially during cooling when the evaporating temperature is low, since the refrigerant always flows through the drier 14, the risk of water blocking caused by freezing of water can be avoided. In addition, since the refrigerant does not flow through the drier 14 during heating, the temperature of the drier 14 can be prevented from rising, and release of adsorbed moisture can be suppressed, thereby preventing an increase in the moisture concentration in the system.

Also, when the control unit 16 stops the compressor 1 during heating of the storage chamber 6, the control unit 16 controls the valves 11 and 13 so that the refrigerant flows through the pipe in which the dryer 14 is provided. In this way, when the compressor 1 stops during heating and the pressure in the system reaches equilibrium, the liquid refrigerant stagnated in the exchanger 5 gradually flows into the exchanger 4 through the dryer 14, and the moisture in the refrigerant can be removed. . In addition, the drier 14 is preferably arranged outside the accommodation chamber 6 and below the branch point of the parallel pipelines. With such a structure, when the compressor 1 is stopped while the interior of the storage chamber 6 is being heated, it is not necessary to switch the flow paths of the parallel pipes when the pressure in the system is balanced. In other words, the liquid refrigerant remaining in the exchanger 5 flows gently while being distributed to the dryer 14 and the exchanger 4 to remove moisture in the refrigerant.

On the other hand, in the process of heating the storage chamber 6, when the control unit 16 starts the operation of the compressor 1, the control unit 16 controls the valves 11 and 13 so that the refrigerant flows through the dryer 14 provided in the passage. The refrigerant does not flow through the dryer 14 in another pipeline other than the pipeline. This prevents the dryer 14 from increasing in temperature, suppresses release of absorbed water, and prevents an increase in the water concentration in the system.

In addition, since the connecting pipe between the exchanger 5 and the capillary tube 10 is designed to be as short as possible, the amount of refrigerant required for heating can be suppressed. In addition, since the liquid refrigerant stays in the drier 14 only during cooling, the difference in the amount of refrigerant staying in the compressor 1 due to the difference in evaporation temperature during cooling and heating can be alleviated.

Next, different configurations of this embodiment will be described using the refrigerant circuit diagram of the cooling and heating system shown in FIG. 3 . The structure of FIG. 3 differs from the structure of FIG. 1 in that a heating check valve (hereinafter referred to as valve) 17 is used instead of valve 11 and a cooling check valve 18 is used instead of valve 13 . The valve 17 is set so that the direction of flow from the capillary 10 to the exchanger 4 is the positive direction, and the reverse direction from the exchanger 4 to the capillary 10 cannot flow. In addition, the valve 18 is set so that the direction of flow from the dryer 14 to the capillary 12 is the positive direction, and the flow in the reverse direction from the capillary 12 to the dryer 14 is disabled. Also, in this case the control unit 16 does not need to control the valves 17 , 18 . Other than that, the configuration is the same as that in FIG. 1 .

With this configuration, the refrigerant flows in the same manner as described above at the time of cooling and heating. In addition, during heating, when the temperature of the storage chamber 6 rises to a set value, the detection unit 19 detects this, and the control unit 16 stops the compressor 1 . At this time, the liquid refrigerant is distributed to the dryer 14 and the exchanger 4 while slowly passing through the capillary tube 10 and the valve 17 from the exchanger 5 with high temperature and pressure to cool down to about the temperature of the outdoor air. The internal pressure gradually reaches equilibrium. In addition, when the liquid refrigerant stays inside the drier 14, synthetic zeolite (not shown) provided inside the drier 14 contacts the liquid refrigerant to remove moisture in the liquid refrigerant.

Then, using check valves 17, 18, the expansion mechanism constituted by capillary tubes 10, 12 is connected to the exchanger 4 with parallel piping. And, when cooling the inside of the storage chamber 6, the control unit 16 switches the valve 2, and the refrigerant flows through one pipe provided with the drier 14 in the passage. On the other hand, when heating the inside of the storage chamber 6 , the control unit 16 makes the refrigerant flow through another pipe other than the pipe in which the dryer 14 is provided in the passage. With such a structure, especially during cooling when the evaporating temperature is low, since the refrigerant always flows through the drier 14, the risk of water blocking caused by freezing of water can be avoided. In addition, since the refrigerant does not flow through the drier 14 during heating, the temperature of the drier 14 can be prevented from rising, and release of adsorbed moisture can be suppressed, thereby preventing an increase in the moisture concentration in the system. An inexpensive mechanism can be realized by using a check valve to switch the flow paths of parallel pipes.

In addition, in this embodiment, although the expansion mechanism composed of the capillary tube 10 and the capillary tube 12 is used, the same expansion mechanism can be obtained by sharing the capillary tube 10A or the electric expansion valve as the single expansion mechanism shown in FIG. Effect. In this case, there is no need to provide a mechanism for adjusting the optimum throttle amount during cooling and heating, or a mechanism for switching between the capillary for cooling and the capillary for heating. Therefore, adjustment of the optimum throttle amount can be realized at low cost. In addition, valves 11 and 13 may be used instead of valves 17 and 18 to be controlled by the control unit 16 in the same manner as in the configuration of FIG. 1 . In addition, heat exchange between capillary tubes 10, 12 or capillary tube 10A, exchanger 5, valve 2 and valve 2 and compressor 1 as expansion mechanism can better improve cooling effect.

Also, when the compressor 1 is stopped during heating, it is preferable to install the exchanger 4 at a position above the drier 14 so that the refrigerant easily stays in the drier 14 . In this way, when the compressor 1 is operating during cooling, the liquid refrigerant stays in the drier 14 and functions as a receiver. Therefore, the difference between the amount of refrigerant necessary for heating and the amount of refrigerant necessary for cooling can be reduced or eliminated.

For example, when R600a, which is a natural refrigerant, is used as a refrigerant, in order to suppress the amount of refrigerant charged, an in-shell low-pressure compressor and mineral oil-based refrigerating machine oil are generally used. Here, the evaporation temperature can be increased to 0 to 30°C when heating with the heat of the atmosphere, compared to -30 to -10°C when the storage chamber 6 is cooled by freezing or refrigerating. As a result, the amount of refrigerant dissolved in the refrigerating machine oil stored in the compressor 1 during heating can also be increased by 5 to 20% by weight. This is because the amount of dissolved refrigerant is 10 to 80 g relative to the weight of 200 to 400 g of refrigerating machine oil, and it is necessary to adjust the difference between the amount of refrigerant required for heating and the amount of refrigerant required for cooling. In this embodiment, if the capacity of the drier 14 is designed to meet the operating conditions of the system or the capacity of each unit, and 10-80g of refrigerant is stored during cooling, the refrigerant will dissolve in the refrigerating machine oil during heating, thus , Can supply insufficient refrigerant amount.

In addition, such a difference between the amount of refrigerant necessary for heating and the amount of refrigerant necessary for cooling has a quantitative difference depending on the type of refrigerant, refrigerating machine oil, and compressor 1 . However, the increase in the amount of refrigerant dissolved in the refrigerating machine oil during heating does not change compared to the cooling time when refrigerating or freezing is required. Therefore, if the capacity of the drier 14 is designed in accordance with the system operating conditions or the capacity of each unit, the same effect can be obtained.

In addition to the more preferable configuration of the cooling and heating system of FIG. 4 and the cooling and heating system of FIG. 4 , a refrigerator incorporating another system will be described below. In addition, these structures can also be combined with the structure of FIG. 1, FIG. 3.

Fig. 5 is a refrigerant circuit diagram of another cooling and heating system according to an embodiment of the present invention. Fig. 6 is a diagram showing the operating range of the cooling and heating system shown in Fig. 5 .

The refrigerator shown in FIG. 5 has a storage room composed of a cooling/heating switchable storage room 6 and cooling-only storage rooms 21 and 22 . The cooling and heating system 51 for cooling or heating the storage chamber 6 is the same as that shown in FIG. 4 . In addition, although the control means 16 etc. are not shown in FIG. 5, the operation|movement of the compressor 1 etc. are controlled by the control means 16 shown in FIG. Among them, the compressor 1 is a high evaporation temperature reciprocating compressor in which a high boiling point refrigerant R600a (CH(CH ₃ ) ₃ ) is used as a refrigerant. The cooling and heating system shown in FIG. 5 also has a cooling system 52 . The cooling system 52 has a compressor (hereinafter referred to as compressor) 29 with a certain speed for low evaporation temperature, an outdoor heat exchanger 25, evaporators 23, 24, expansion valves 26, 27 and pipes connecting these components in a ring shape. The cooling cycle cools the storage chambers 21 and 22 . In other words, the cooling system 52 cools the storage chambers 21 and 22 located in a different location from the storage chamber 6 which is a cooling and heating location of the exchanger 5 .

The exchanger 5 and the exchanger 4 are fin-tube heat exchangers for condensing or evaporating the refrigerant, and are designed to balance the condensing ability and the frosting ability. For example, the exchanger 5 has a heating capacity of 150-200W under the condition that the difference between the condensation temperature and the intake air temperature is 10°C, and has a heating capacity of 150-200W under the condition that the difference between the evaporation temperature and the intake air temperature is 10°C. 200W cooling capacity.

In addition, the capillary 10A is used in both heating and cooling modes to reduce the pressure of the passing refrigerant and adjust the evaporation pressure. When cooling the storage chamber 6, the fan 7 is driven to keep the running compressor 1 cool. At the same time, when the storage chamber 6 is heated, it is driven when the compressor 1 reaches an abnormally high temperature of 80°C or higher to cool the compressor 1 to 70°C. Under stable conditions below ℃. In other words, a separate fan 7 is designed to cool the compressor 1 , and the fan 7 is operated while the compressor 1 is in operation in the case of cooling the housing chamber 6 . In addition, when the outside air is extremely low temperature, etc., the fan 7 may be stopped under a given low outside air temperature condition. When the storage chamber 6 is heated, the fan 7 is stopped when the temperature of the compressor 1 is lower than a predetermined temperature. In this way, the fan 7 is operated during cooling, which can lower the temperature of the compressor 1 and improve the efficiency of the compressor. At the same time, by stopping the fan 7 during heating, the condensing pressure can be optimized to rise to a pressure equivalent to the temperature in the storage room during intermittent operation. With the intermittent operation of the compressor 1, the heating loss can be reduced and high efficiency can be achieved.

The compressor 29 forms a cooling cycle together with the outdoor heat exchanger 25 , evaporators 23 , 24 , and expansion valves 26 , 27 to cool the storage chambers 21 , 22 . The compressor 29 is a compressor used in a household refrigerator using R600a as a refrigerant. Under the cooling condition of condensing temperature of 54.4°C and evaporating temperature of -12.2°C, it has a freezing capacity of 250W. The expansion valves 26 and 27 also have a closing function while reducing the pressure of the refrigerant passing through them respectively. The fan 30 is driven in conjunction with the cooling and heating system, and cools the outdoor heat exchanger 25 and the compressor 8 .

Here, as shown in FIG. 6 , the region 31 of the operating range of the cooling and heating system in the heating mode and the region 32 of the operating range in the cooling mode are approximately the same in relation to the condensing temperature and the evaporating temperature. In other words, in the heating mode in which the condensing temperature is high compared to the region 32, since the cooling heating system operates in the region 31 having a high evaporation temperature compared to the cooling mode, the fixed resistance capillary 10A can be used in both heating and cooling. Used in two modes.

In addition, in FIG. 6 , directions p1 and p2 represent directions in which the operating state changes when the capacity of the compressor 1 is variable, and directions q1 and q2 represent directions in which the operating state changes when the condensation temperature is variable. That is, even if the fixed resistance capillary 10A is used, by changing the capacity of the compressor 1, the evaporation temperature can be controlled to some extent. For example, if the capability of the compressor 1 is changed so that the evaporating temperature does not become below 5° C. in the heating mode, frosting in the exchanger 4 as an evaporator can be avoided, thereby reducing dew condensation.

Next, the operation of the refrigerator configured as above will be described. In the case of cooling the storage chamber 6, the valve 2 is switched to the cooling side, and the compressor 1 is driven. The refrigerant discharged from the compressor 1 passes through the valve 2 , is condensed by the exchanger 4 , is decompressed by the capillary 10A, and is supplied to the exchanger 5 . Then, the refrigerant evaporated in the exchanger 5 returns to the compressor 1 . At this time, when the storage chamber 6 is close to a predetermined temperature, the compressor 1 is decelerated to lower its capacity, so that the evaporation temperature can be raised and the cooling efficiency can be improved. For example, under a stable operating condition where the outside air temperature is 15° C., since the heat load of the storage chamber 6 is about 100 to 200 W when it is stable, the compressor 1 is controlled so that the evaporation temperature is -20 to -15°C. ℃, the condensing temperature is 30-40 ℃, and the operation is basically continuous under the high-speed rotation of 58-72rps. Thereafter, when the storage chamber 6 reaches a predetermined temperature, the operation of the compressor 1 is stopped.

Also, for example, when the outside air temperature is 15° C., when the cooling is started from the power on, since the temperature of the storage chamber 6 is high, the evaporation temperature of the exchanger 5 rises, and the cooling capacity increases. In other words, the automatic adjustment function of the ability works. Therefore, when cooling is started from power-on, the compressor 1 is continuously operated at a high rotation speed, and high-capacity operation conditions are established where the evaporating temperature is -10°C and the condensing temperature is 50°C. Thereafter, as the temperature of the storage chamber 6 decreases, the above-described stable operating conditions are automatically transitioned to.

On the other hand, when heating the storage chamber 6, the valve 2 is switched to the heating side, and the compressor 1 is driven. The refrigerant discharged from the compressor 1 passes through the valve 2 , is condensed by the exchanger 5 , is decompressed by the capillary 10A, and is supplied to the exchanger 4 . Then, the refrigerant evaporated in the exchanger 4 returns to the compressor 1 .

At this time, for example, when the outside air temperature is 15° C., the thermal load when the storage chamber 6 is stable is about 100 to 200 W. Therefore, the compressor 1 is controlled so as to continuously operate at a low rotational speed of 27 to 35 rps under the operating conditions of an evaporating temperature of 5 to 10°C and a condensing temperature of 55 to 65°C. Therefore, when operating at a high rotational speed, the capacity becomes excessive, and the condensation temperature of the exchanger 5 rises beyond the limit of the compressor 1, resulting in a decrease in durability. In addition, the compressor 1 needs to be operated intermittently, and useless operation occurs until the temperature of the exchanger 5 reaches a predetermined temperature from the stopped state, and the overall efficiency is lowered.

In addition, for example, when the outside air temperature is 15° C., when heating is started when the power is turned on, the storage chamber 6 usually needs to be heated at about 400 W. In this case, the compressor 1 is controlled to continuously operate at a high rotational speed of 72 rps under the operating conditions of an evaporating temperature of +0 to +5°C and a condensing temperature of 70 to 75°C. Here, the important point is that the automatic adjustment mechanism of the capacity observed in the case of cooling does not work in the case of heating. When the excess capacity of the compressor 1 is too large, the condensation temperature of the exchanger 5 will increase, and the heating capacity will increase. tends to increase further. In addition, when the temperature of the storage chamber 6 is lowered, the condensation temperature becomes lower, and conversely, since the heating capacity tends to decrease, control to increase the heating capacity is essential. In this embodiment, the fan 7 is stopped in order to suppress unnecessary heat radiation from the surface of the compressor 1 . Furthermore, it is desirable to maintain the condensation temperature at 70°C to 75°C by energizing the auxiliary heater 39 attached to the exchanger 5 at the start-up initial stage when the power is turned on.

Therefore, in this configuration, in order to effectively cool and heat the storage chamber 6, the rotation speed of the compressor 1 can be maintained at a relatively high speed when the cooling is started from the time when the power is turned on. On the other hand, when heating is started when the power is turned on, it is necessary to gradually reduce the rotational speed of the compressor 1 to 27 to 35 rps to adjust the capacity as the temperature in the storage chamber 6 rises. In addition, in the process of temperature rise in the storage chamber 6, in order not to make the condensing temperature exceed the limit of the compressor 1, it is better to install a temperature sensor for detecting the condensing temperature of the exchanger 5. At the same time, when the condensing temperature of the exchanger 5 When the temperature exceeds a predetermined value, control is performed to reduce the rotational speed of the compressor 1 .

In addition, in this embodiment, it is estimated that the cooling load of the storage chamber 6 at 15° C. is about 100 to 200 W when the cooling is stable, and the heating load of the storage chamber 6 is about 100 to 200 W when the heating is stable. This is a general important condition when using a refrigerator in an automatic vending machine. However, in another automatic vending machine, the cooling load is almost the same as the heating load at a normal temperature of 15 to 25° C., and the evaporation temperature during cooling may be lower than that during heating. Therefore, there is no change in the fact that it is necessary to reduce the capacity of the compressor 1 in order to suppress the excess heating capacity when the heating is stable.

Next, in this embodiment, an example will be described in which both the auxiliary heater 39 and the cooling and heating system heat the storage chamber 6 when the heating is started when the power is turned on. However, when heating is started from power-on, only the auxiliary heater 39 is used, and when the temperature of the storage chamber 6 is stabilized, even if the heating capacity of the cooling and heating system is used to keep warm, the heating efficiency at the time of keeping warm can be improved.

In addition, in this embodiment, the capillary 10A is used as the fixed resistance of the cooling and heating system, but variable resistance such as an electric expansion valve may be used. In the case of using variable resistance, the condensing temperature is difficult to rise, and when the heating is started when the power is turned on, by reducing the variable resistance, the heating capacity of the cooling and heating system when the power is turned on can be improved, and at the same time, auxiliary heating can be realized. Low input of device 39. On the other hand, when cooling the storage chamber 6, it is not necessary to fine-tune the resistance, and if a capillary tube is used, the cooling effect can be improved by exchanging heat with the suction pipe of the compressor 1.

In addition, in this embodiment, the evaporation temperature of the exchanger 4 when the storage chamber 6 is heated can be efficiently adjusted arbitrarily within the range of 0 to 10°C. In particular, when an automatic vending machine with a refrigerator is installed indoors and the dew condensation water in the storage chamber 6 cannot be discharged, it is desirable to operate the cooling and heating system only within the range where dew does not condense. In addition, under high-humidity conditions such as rainy days, it is desirable to switch to heating with only the auxiliary heater 39 . In addition, a dew condensation sensor may be provided on the inlet pipe of the exchanger 4 in the case of heating the storage chamber 6 to detect such a situation.

As mentioned above, the refrigerator shown in FIG. 5 is equipped with the dedicated cooling/heating system 51 for cooling/heating the storage chamber 6 different from the cooling system 52 for the storage chambers 21 and 22 . In addition, the cooling and heating system 51 has a compressor 1 using R600a as a refrigerant, exchangers 4 and 5, a valve 2, and a capillary tube 10A. This cooling and heating system maintains a high temperature condition with an evaporation temperature of -10 to 10°C and reduces the compression ratio by exchanging heat with the outdoor atmosphere with a low-cost structure with a small number of parts. In addition, by using the compressor 1 using R600a as the refrigerant, it is possible to widely apply a reciprocating compressor for low evaporation temperature using the high-boiling point refrigerant R134a (CH ₂ FCF ₃ ) as the refrigerant that can be mass-produced. In addition, the durability of the compressor 1 can be easily ensured and high efficiency of the compressor 1 can be easily ensured under severe heating conditions with an evaporating temperature of -10°C to 10°C and a condensation temperature of 60°C to 80°C.

As an example, for various refrigerants used in refrigeration equipment, the low pressure, high pressure, compression ratio, discharge gas temperature, and volumetric capacity and theoretical efficiency under the conditions of evaporating temperature of -15°C/condensing temperature of 70°C The relative values of are shown in Table 1. In addition, Table 2 shows the relative values of low pressure, high pressure, compression ratio, exhaust gas temperature, volume capacity and theoretical efficiency under the condition of evaporating temperature of 5°C/condensing temperature of 70°C. Among them, the values in Table 1 and Table 2 are the calculated values under the conditions of adiabatic compression under subcooling at 0°C and suction gas temperature at 32°C. In addition, R407C (a mixture of CH ₂ F ₂ , CHF ₂ CF ₃ , and CH ₂ FCF ₃ in a ratio of 23:25:52) in Tables 1 and 2 is selected as a low pressure with the average temperature of the liquidus line and the gaseous line at the specified temperature. pressure and high pressure.

Table 1 type high boiling point refrigerant low boiling point refrigerant Refrigerant number R134a R600a R407C R290 Boiling point (°C) -26.1 -11.6 (-40) -42.1 Low pressure (kPa) 164 89 300 292 High pressure (kPa) 2117 1086 3300 2586 compression ratio 12.9 12.2 11.0 8.9 Exhaust gas temperature (℃) 123 105 137 120 volume capacity 52 29 88 77 theoretical efficiency 75 80 72 74

As shown in Table 1, under the condition of evaporating temperature of -15°C/condensing temperature of 70°C, the compression ratio exceeds 12 when high boiling point refrigerant R134a or R600a is used. Therefore, under actual operating conditions where overcompression occurs, the discharge gas temperature may rise abnormally, which may reduce the durability of the compressor. In addition, when low boiling point refrigerant R407C or R290 (CH ₃ CH ₂ CH ₃ ) is used, the high pressure exceeds 2.5 MPa. Therefore, there is also a concern that the load resistance of the bearing portion is insufficient to cause abnormal wear and reduce the durability of the compressor.

Table 2 type high boiling point refrigerant low boiling point refrigerant Refrigerant number R134a R600a R407C R290 Boiling point (°C) -26.1 -11.6 (-40) -42.1 Low pressure (kPa) 243 130 603 406 High pressure (kPa) 2117 1086 3300 2586 compression ratio 8.7 8.4 5.5 6.4 Exhaust gas temperature (℃) 112 95 111 109 volume capacity 100 55 156 131 theoretical efficiency 100 106 95 97

On the other hand, as shown in Table 2, when the evaporating temperature is 5°C/condensing temperature is 70°C, when the high-boiling point refrigerant R134a or R600a is used, the compression ratio is less than 9, which is within the usual usable range. Furthermore, since R600a has a smaller capacity and higher efficiency than R134a, it is suitable for use in applications where a heating system for heating a storage room surrounded by an insulating material in a vending machine has a smaller capacity and higher efficiency is required. In addition, under the condensing temperature condition, when the low-boiling-point refrigerant R407C or R290 is used, the high-pressure pressure increases, and there is no change in the problem of compressor durability.

In addition, by using a reciprocating compressor that can maintain the evaporation pressure in the shell, it is possible to optimize the characteristics that the condensing pressure rises to an equivalent temperature and pressure in the storage during intermittent operation, and can reduce the heating consumption with the intermittent operation of the compressor to achieve high efficiency. efficiency.

In the case of cooling/heating the storage chamber 6, it is preferable to perform high-speed operation during cooling operation with relatively low evaporation temperature and relatively low suction gas density, and to perform high-speed operation during heating operation with relatively high evaporation temperature and relatively high suction gas density. When running at low speed. Therefore, substantially the same cooling capacity and heating capacity can be obtained under respective operating conditions, and a capacity that is not too insufficient as a compressor of the cooling and heating system can be realized. In particular, in heating where the condensing temperature is high and the heating loss increases due to the intermittent operation of the compressor 1, the efficiency can be further improved by substantially continuous operation.

In cooling the storage chambers 21 and 22, the compressor 29 is driven. The refrigerant discharged from the compressor 29 is condensed by the heat exchanger 25, decompressed by the expansion valves 26 and 27, and supplied to the evaporators 23 and 24, respectively. Then, the refrigerant evaporated by the evaporators 23 and 24 returns to the compressor 29 .

When the storage chambers 21 and 22 reach a given temperature, the expansion valve 26 or expansion valve 27 is closed, and when the storage chambers 21 and 22 both reach a given temperature, the operation of the compressor 29 is stopped. These controls can be performed by the control unit 16, or a control unit can be provided separately. For example, when the external air temperature is 15°C, since the thermal load of the storage chambers 21 and 22 is about 100 to 300W when they are stable, the operating conditions of the evaporation temperature are -25 to 15°C and the condensation temperature is 30 to 40°C. Down, the compressor 29 operates intermittently.

As disclosed in Japanese Patent Application Laid-Open No. 2002-174478, in the conventional structure, the low-boiling point refrigerant R407C is used as the refrigerant, and under the cooling conditions of the condensation temperature of 54.4°C and the evaporation temperature of -12.5°C, by having 400 ~ 600W refrigeration capacity compressor for cooling and heating. In contrast, in this embodiment, the cooling of the storage chamber 6 is performed by the compressor 1 , and the cooling of the storage chambers 21 and 22 is performed by the compressor 29 . Therefore, high-efficiency high-boiling-point refrigerant R600a can be used as a refrigerant, and a low-capacity, but inexpensive, high-efficiency compressor for household refrigerators can be used. Therefore, the efficiency can be further improved also during cooling.

When the storage chambers 21 and 22 are cooled from when the power is turned on, the automatic capacity adjustment function works similarly to the cooling of the storage chamber 6, so fine adjustment of the expansion valve 26 or expansion valve 27 is unnecessary. In addition, in the state where only one of the storage chambers 21 and 22 is cooled, one expansion valve can be closed to reduce the circulation volume, so the capacity can be adjusted to lower the evaporation temperature below -20°C.

Example 2

Fig. 7 is a refrigerant circuit diagram of the cooling and heating system according to Embodiment 2 of the present invention. The refrigerator of this embodiment has a storage room 6, a compressor 1, an evaporator 5B and a condenser 5A, an evaporator 4A and a condenser 4B, a three-way switching valve (hereinafter referred to as a valve) 2A, a two-way valve (hereinafter referred to as a valve) ) 11, 13 and dryer 14. The compressor 1, the condenser 4B, the drier 14, the valve 13, the capillary tube 12 and the evaporator 5B are connected in an annular shape by the first pipeline through the valve 2A in the order mentioned above. In addition, the compressor 1, the condenser 5A, the capillary tube 10, the valve 11, and the evaporator 4A are connected in an annular form by the second pipe in the above-mentioned order through the valve 2A. The evaporator 5B and the condenser 5A are disposed inside the storage chamber 6 , and the evaporator 4A and the condenser 4B are disposed outside the storage chamber 6 . The valves 2A, 11, and 13 switch the refrigerant flow paths during cooling and heating. The valve 2A is a switching valve for selecting either one of the first pipe 1 and the second pipe.

Any one of the condenser 5A and the evaporator 5B is a finned tube heat exchanger. On the premise of not having to consider frosting and giving priority to high condensing capacity, the condenser 5A is designed to be connected by tubes so that the interval between the fins and the tubes is relatively narrow, and at the same time, the flow of the refrigerant and the air are countercurrent. As a result, it has a heating capacity of 200 to 300 W when the difference between the condensation temperature and the intake air temperature is 10°C. On the other hand, evaporator 4A is designed in the same manner as evaporator 5B, but frosting at low outside air temperature is considered.

The compressor 1 here is to replace the refrigerant and refrigerator oil of the low evaporation temperature reciprocating compressor used in household refrigerators using R134a as the refrigerant, and seal the refrigerant R600a and mineral oil-based refrigerator oil into the in. This reciprocating compressor for low evaporating temperature is driven by a DC transformer, converted into a freezing capacity with a condensing temperature of 54.4°C and an evaporating temperature of -23.3°C under standard conditions, and its capacity can be changed within the range of 100 to 250W. Similarly, the compressor 1 filled with refrigerant R600a and mineral oil-based refrigerating machine oil has a refrigerating capacity of 70 to 180 W under the cooling conditions of a condensation temperature of 54.4°C and an evaporation temperature of -12.2°C. In addition, it has a heating capacity of 150 to 400 W under the heating conditions of a condensation temperature of 70°C and an evaporation temperature of 5°C.

Fig. 8 is a control block diagram of the cooling and heating system shown in Fig. 7 . In this structure, only the valve 2 in the structure described with reference to FIG. 2 in Embodiment 1 is replaced with the valve 2A, and therefore, its detailed description is omitted.

Next, the operation of the refrigerator configured as above will be described. When the storage chamber 6 is cooled, the control unit 16 switches the valve 2A to the cooling side to drive the compressor 1 . The refrigerant discharged from the compressor 1 passes through the valve 2A, is condensed by the condenser 4B, is decompressed by the capillary 12, and is supplied to the evaporator 5B. Then, the refrigerant evaporated in the evaporator 5B returns to the compressor 1 . At this time, the condensed and liquefied liquid refrigerant supplied to the condenser 4B is supplied to the drier 14 .

When the storage chamber 6 is close to a predetermined temperature, the detection unit 19 detects this, and the control unit 16 reduces the capacity of the compressor 1 by decelerating, thereby increasing the evaporation temperature and improving the cooling efficiency. For example, when the outside air temperature is 15° C., the thermal load when the storage chamber 6 is stable is about 100 to 200 W. Therefore, the compressor 1 is controlled to operate substantially continuously at a high rotational speed of 58 to 72 rps under the operating conditions of an evaporating temperature of -20 to -15°C and a condensing temperature of 30 to 40°C. Then, the control unit 16 stops the operation of the compressor 1 when the accommodation chamber 6 reaches a given temperature.

Also, for example, when heating is started when the power is turned on at an outside air temperature of 15° C., since the temperature of the storage chamber 6 is high, the evaporation temperature of the evaporator 5B rises and the cooling capacity increases. In other words, the automatic adjustment function of the ability works. Therefore, the capacity of the compressor 1 can be adjusted and fixed in accordance with the steady state without finely controlling the capacity of the compressor 1 .

On the other hand, when the storage chamber 6 is heated, the control unit 16 switches the valve 2 to the heating side to drive the compressor 1 . The refrigerant discharged from the compressor 1 passes through the valve 2A, is condensed by the condenser 5A, is depressurized by the capillary tube 10, and is supplied to the evaporator 4A. Then, the refrigerant evaporated by the evaporator 4A returns to the compressor 1 . At this time, almost no liquid refrigerant stagnates inside the drier 14, but is filled with a saturated gas refrigerant whose evaporation temperature is substantially the same as that of the evaporator 4A. Therefore, in this structure, it is also possible to obtain the same

Example 1 has the same effect.

For example, when the outside air temperature is 15° C., the thermal load when the storage chamber 6 is stable is about 100 to 200 W. Therefore, the compressor 1 is controlled so as to continuously operate at a low rotational speed of 27 to 35 rps under the operating conditions of an evaporating temperature of 5 to 10°C and a condensing temperature of 55 to 65°C. Therefore, when operating at a high rotation speed, the capacity becomes excessive, and the condensation temperature of the condenser 5A rises beyond the limit of the compressor 1, resulting in a decrease in durability. In addition, the compressor 1 needs to be operated intermittently due to excess capacity, and the operation becomes useless until the temperature of the condenser 5A reaches a predetermined temperature from a stopped state, resulting in a decrease in overall efficiency.

In addition, for example, when the heating is started from the time when the power is turned on at an outside air temperature of 15° C., it is usually necessary to heat the storage chamber 6 at about 400 W. In this case, the compressor 1 is controlled to continuously operate at a high rotational speed of 72 rps under the operating conditions of an evaporating temperature of +0 to +5°C and a condensing temperature of 70 to 75°C. Here, the important point is that the automatic adjustment mechanism of the capacity observed under the cooling condition does not work under the heating condition. In addition, when the temperature in the housing chamber 6 decreases, the condensation temperature becomes lower. On the contrary, due to the heating capacity The tendency to decrease, therefore, the control to improve the heating capacity is essential. For example, it is preferable to increase the opening of the valve 11 to continuously operate the compressor 1 at a high rotational speed, and to stop the fan 7 in order to suppress unnecessary heat radiation on the surface of the compressor 1 .

Therefore, in the structure of this embodiment, in order to realize the cooling and heating of the storage chamber 6 more effectively, when the cooling starts when the power is turned on, the rotation speed of the compressor 1 can be maintained at a relatively high rotation speed. . On the other hand, when heating is started when the power is turned on, the rotational speed of the compressor 1 gradually decreases to 27 to 35 rps as the temperature in the storage chamber 6 rises, and capacity adjustment is required. In addition, in the process of temperature rise in the accommodation chamber 6, in order to keep the condensation temperature from exceeding the limit of the compressor 1, it is preferable to install a temperature sensor for detecting the condensation temperature of the condenser 5A, and at the same time, when the condensation temperature of the condenser 5A When the temperature exceeds a given value, control is performed so that the rotational speed of the compressor 1 decreases.

In addition, if the storage chambers 21 and 22 and their cooling system are provided separately as in the first embodiment, the capacity of the cooling system can be reduced, and as a result, the high-boiling-point refrigerant R600a that can improve the theoretical efficiency can be used.

In addition, as in the first embodiment, an auxiliary heater 39 may be provided. Furthermore, although the capillary tubes 10 and 12 are used as the fixed resistance of the cooling and heating system, a variable resistance such as an electric expansion valve may also be used in combination with the valves 11 and 13 . Alternatively, a check valve may be used for the valves 11 and 13 similarly to the configuration of FIG. 3 .

As described above, the present embodiment can also obtain the same effect as that of the first embodiment.

Example 3

Fig. 9 is a refrigerant circuit diagram of the cooling and heating system according to Embodiment 3 of the present invention. Fig. 11 is a perspective view of the outdoor heat exchanger of this embodiment.

The cooling and heating system of this embodiment includes a cooling and heating system 51 and a cooling system 52 . The basic structure of the cooling and heating system 51 is the same as that of FIG. 3 of the first embodiment. In addition, the basic structure of the cooling system 52 is the same as the cooling system shown in FIG. 5 . Compressor 1 is arranged in the heat-insulating cover not shown in figure, while being cooled by fan 7, also respectively in indoor heat exchanger (hereinafter referred to as exchanger) 5, evaporator 23, evaporator 24, outdoor heat exchanger (hereinafter referred to as heat exchanger) On the switch) 61, fans 8, 41, 42, 62 are independently arranged.

The difference between the structure of this embodiment and the structure shown in FIG. 5 lies in the switch 61 . The exchanger 61 is constituted by a two-pass finned tube heat exchanger. One passage is connected to the cooling and heating system 51, and the accommodation chamber 6 serves as an evaporator when heated and a condenser when cooled. Another passage is connected to the cooling system 52, which acts as a condenser.

The refrigerant piping connected to the cooling and heating system 51 is preferably provided on the downstream side of the refrigerant piping of the cooling system 52 . Furthermore, the refrigerant in the cooling system 52 flows in from the inlet pipe 53 arranged in the lower central stage of the three rows as shown by the dotted arrow in FIG. The outlet pipe 54 of the side lower section flows out. On the other hand, the refrigerant during heating by the cooling and heating system 52 flows in from the inlet pipe 55 arranged on the upper downstream side, flows toward the lower stage, and flows out from the outlet pipe 56 arranged on the lower downstream side as shown by the solid arrow. Also, during cooling, the refrigerant flows in the opposite direction. A structure as described above is preferred. Furthermore, it is preferable to arrange the outlet duct 56 adjacent to the inlet duct 53 . In addition, a dew condensation sensor 57 is attached to the inlet duct 55 .

Fig. 10 is a control block diagram of the cooling and heating system shown in Fig. 9 . The control unit 16 controls the expansion valves 26, 27, the fan 26, and the four-way switching valve (hereinafter referred to as valves) according to the input from the input unit 15, the detection unit 19, and the condensation sensor 57, or the operating status of the compressors 1 and 29. 2. Operation of compressors 1, 29, auxiliary heater 39, etc.

Next, the operation and function of the cooling and heating system configured as above will be described.

First, when cooling the storage chamber 6, the refrigerant discharged from the compressor 1 is supplied to the exchanger 61 after being condensed and liquefied by switching the flow path with the valve 2 as indicated by the dotted arrow in FIG. 9 . The refrigerant discharged from the exchanger 61 is supplied to the dryer 14 . The refrigerant has a temperature of 30 to 40° C. which is substantially the same as that of the exchanger 61 . At this time, the liquid refrigerant stays inside the drier 14, and at the same time, moisture in the liquid refrigerant is removed.

Then, the refrigerant discharged from the drier 14 passes through the check valve 18, is decompressed by the cooling capillary 12, is supplied to the exchanger 5, and evaporates. The gas refrigerant flows back to compressor 1 through valve 2 again. The evaporation temperature of the exchanger 5 varies greatly depending on the set temperature of the storage chamber 6 . Generally, in the case of cooling filled beverages, etc., the set temperature is 5-10°C, and the evaporation temperature of the exchanger 5 is -15--5°C.

In addition, it is preferable to install the capillary tube 12 for cooling in contact with the outlet pipe during cooling of the exchanger 5, and obtain a large supercooling by means of heat exchange to improve the cooling capacity.

In addition, when heating the storage chamber 6, as shown by the solid arrow in FIG. 9, the refrigerant|coolant discharged from the compressor 1 switches the flow path by the valve 2, is supplied to the exchanger 5, and is condensed and liquefied. The temperature of the refrigerant varies greatly depending on the set temperature of the storage chamber 6 . Generally, in the case of heating and filling beverages, the set temperature is 50-60°C, and the condensation temperature of the exchanger 5 is 60-80°C.

In addition, it is preferable to cover the heating refrigerant pipe from the compressor 1 to the exchanger 5 with a heat insulating material. By preventing heat release from the heating refrigerant pipe, heating capacity and heating efficiency can be improved.

The refrigerant discharged from the exchanger 5 is immediately decompressed through the capillary tube 10 for heating, then supplied to the exchanger 61 through the check valve 17, evaporated and vaporized, and the gas refrigerant passes through the valve 2 again, and returns to the compressor 1. Generally, when the outside air temperature is low, it is necessary to lower the evaporation temperature of the exchanger 61 , especially when the outside air temperature is below 5° C., the evaporation temperature must be below 0° C., and frost will form on the exchanger 61 . In addition, when the external air temperature is high and the humidity is high, when the temperature of the tube surface of the exchanger 61 or the temperature of the fins drops to the dew point temperature, dew condensation occurs.

However, in the exchanger 61 of this embodiment, when the cooling system 52 is in operation, the passage connected to the cooling system 52 acts as a condenser, and the temperature of the fins around the passage increases. Therefore, under the condition that the cooling and heating system 51 and the cooling system 52 work at the same time, heat exchange of the waterfall evaporator can be performed through the fins. In addition, air heated and warmed by the condenser can be sucked into the evaporator, and the cooling and heating system 51 can be operated at a high evaporation temperature of 0 to 10°C. In this way, the compression ratio can be reduced even under severe heating conditions where the condensation temperature is 60 to 80° C., thereby improving the efficiency of the compressor 1 . In addition, an increase in the efficiency of the compressor 8 can also be achieved by lowering the condensation temperature in the cooling system 52 .

Furthermore, by setting the evaporation temperature of the cooling/heating system 51 to 0° C. or higher, it is also possible to prevent the exchanger 61 from being frosted. In addition, even when the outside air temperature is high and the humidity is high, the temperature of the fins of the exchanger 61 hardly lowers the dew point temperature, and the occurrence of dew condensation can be effectively suppressed.

In addition, if the outlet pipe 56 and the inlet pipe 53 are arranged close to each other in the exchanger 61, the degree of superheat of the cooling and heating system 51 can be increased, and the heating capacity and heating efficiency can be improved.

In addition, in this embodiment, the refrigerant pipeline of the cooling and heating system 51 is arranged downstream of the refrigerant pipeline of the cooling system 52 . When using three rows of heat exchangers, a structure in which the refrigerant pipes of the cooling system 51 are sandwiched between the refrigerant pipes of the cooling system 52 can be employed.

Moreover, if the dew condensation sensor 57 is installed on the heating inlet pipe 31 of the cooling and heating system 51 , when dew condensation is detected for a certain period of time, the cooling and heating system 51 can be stopped and switched to heating by the heater 39 . This prevents condensation water from leaking out of the refrigerator without stopping the heating function. In addition, in this embodiment, the inlet pipe 55 is arranged at the upper part, so that even in the case of dew condensation, the dew condensation water can be evaporated before reaching the bottom of the exchanger 61 .

In addition, when the cooling by the cooling system 52 and the heating by the cooling/heating system 51 are operated simultaneously, the heat exchange capacity of the exchanger 61 is increased compared to the case where each is operated independently. As a result, the cooling capacity and the heating capacity are rapidly increased, which causes frequent start-up and stop, and reduces the simultaneous operation rate. Therefore, it is best to adjust by reducing the air volume of the fan 62, so that the amount of heat exchange between the exchanger 61 and the air is reduced, without sharply increasing the capacity of the cooling system 52 and the cooling and heating system 51. In this way, while increasing the simultaneous operation rate of the cooling system 52 and the cooling and heating system 51 , the cooling loss and heating loss caused by starting and stopping are also reduced, thereby reducing the power consumption of the fan 62 . In addition, the temperature of the exchanger 61 can be measured, and the fan 38 can be stopped as needed.

As described above, in this embodiment, a dedicated cooling and heating system 51 for cooling and heating the storage chamber 6 is provided, which is different from the cooling system 52 for cooling the storage chambers 21 and 22 . Moreover, the system of Example 1 or 2 is used as the cooling/heating system 51 . Therefore, the evaporation temperature during heating can be set higher, and at the same time, use the waste heat of the cooling system 52 to maintain the evaporation temperature during heating of the cooling and heating system 51 at a high temperature of 0 to 10°C, thereby reducing the compression ratio. . In this way, the efficiency of the compressor 1 can be improved, and the heating efficiency of the cooling and heating system 51 can be improved. Therefore, compared with a heater whose heating efficiency is about 1, such as an electric heater, a heating efficiency of about 2 times can be easily realized. If such a refrigerator is applied to a vending machine, it is possible to significantly reduce power consumption.

The waterfall evaporator heat exchanger 61 of this embodiment is composed of a two-pass finned tube heat exchanger having a refrigerant pipe connected to the cooling system 52 and a refrigerant pipe connected to the cooling and heating system 51 . Furthermore, by bringing the outlet pipe 56 of the cooling and heating system 51 close to the inlet pipe 54 of the cooling system 52 during heating, the degree of superheat of the cooling and heating system 51 can be increased. Therefore, heating capacity and heating efficiency are improved.

In addition, when the dew condensation sensor 57 is installed on the inlet pipe 55 of the cooling and heating system 51 of the exchanger 61 during heating, and when dew condensation is detected within a certain period of time, the cooling and heating system 51 is stopped, and the auxiliary heater 39 is switched to use. heating. In this way, water leakage due to dew condensation can be prevented without stopping the heating of the product.

In addition, in this embodiment, when the cooling of the cooling system 52 and the heating of the cooling and heating system 51 are operated simultaneously, the air volume of the fan 62 is reduced. In this way, the power consumption of the fan 62 can be reduced while preventing a drastic increase in the capacities of the cooling system 52 and the cooling and heating system 51 .

Furthermore, since the cooling and heating system 51 and the cooling system 52 can be operated independently, even if one of the cooling system 52 and the cooling and heating system 51 stops, the other continues to operate as usual. In addition, since the heat exchanger 61 exchanges heat with the outdoor air, it is not necessary to set the evaporation temperature below -10°C.

In FIG. 9 , the cooling and heating system shown in FIG. 3 is used as the cooling and heating system 51 , but the cooling and heating systems shown in FIGS. 1 and 4 may also be used.

As mentioned above, the cooling and heating system of this embodiment utilizes the waste heat of the cooling system 52 to heat the cooling and heating system 51, which can improve the heating efficiency. This system can also be used for cup-type vending machines that require energy saving during heating and cooling. Such cup-type vending machines display products that switch and store hot drinks and cold drinks or supply a small amount of boiling water.

Fig. 12 is a schematic diagram of an automatic vending machine equipped with the refrigerator shown in Fig. 9 . In addition, in FIG. 12, the cooling heating system 51 and the cooling system 52 are not shown. The automatic vending machine can also be loaded with any one of the refrigerators shown in Fig. 1, Fig. 3, Fig. 4, Fig. 5 and Fig. 7, to replace the refrigerator shown in Fig. 9 . On the front of the vending machine, there is provided a cash collection section 71 for collecting money for items 73 stored in the storage chamber 6 (or storage chambers 21, 22), such as canned fruit juice. The equivalent money collected by the money collection unit 71 may be cash, or a signal of a wireless device such as a credit card or a mobile phone. After receiving the equivalent money, the collection unit 71 controls the carrying unit 72 to carry out the article 73 from the storage chamber 6 . Items 73 are then fed out of the vending machine through passage 74 . The cash collection unit 71 and the transfer unit 72 can employ well-known techniques, so detailed description thereof will be omitted. In addition, other control means 75 different from the payment receiving part 71 may be provided to control their operations.

As described above, the cooling and heating system of the present invention opens and closes the refrigerant circuit of the dryer provided between the expansion mechanism and the outdoor heat exchanger. Therefore, especially when products such as canned beverages are heated to a high temperature of 50 to 100° C., the increase of the water content in the system can be suppressed, and at the same time, the necessary amount of refrigerant can be suppressed to a minimum. Therefore, it can be used for the purpose of improving the reliability of cooling and heating systems for switching between cooling and heating of merchandise showcases, food storages, and automatic vending machines.

In addition, even if it implements independently of the structure distribution concerning the dryer 14 using the characteristic structure demonstrated in each figure, each effect can be acquired.

Claims (24)

1. A cooling and heating system, characterized in that it comprises: a first heat exchanger; second heat exchanger; expansion mechanism; compressor; connecting the above-mentioned compressor, the above-mentioned expansion mechanism, the above-mentioned first heat exchanger and the above-mentioned second heat exchanger to form an annular pipeline; A switching valve for selecting which of the flow paths formed by the above-mentioned pipes; one of the flow paths formed by the above-mentioned pipes passes through the above-mentioned second heat exchanger, the above-mentioned expansion mechanism, and the above-mentioned first heat exchanger sequentially from the above-mentioned compressor Then return to the cycle formed by the compressor; or the other is to return to the cycle formed by returning to the compressor and returning to the compressor after passing through the first heat exchanger, the expansion mechanism and the second heat exchanger in sequence from the compressor; The first and second parallel pipelines connected in parallel between the expansion mechanism and the second heat exchanger; a drier arranged in the above-mentioned first parallel pipeline; Used to control the first and second valves respectively arranged on the first and second parallel pipes; through control, when the first heat exchanger works in cooling mode, the refrigerant flows through the first Parallel pipes for flowing refrigerant through said second parallel pipes with said first heat exchanger operating in heating mode; and A control unit that controls at least the switching valve to switch the operating state of the first heat exchanger. 2. The cooling and heating system according to claim 1, wherein the first valve and the second valve are two-way valves, and the control unit controls the first valve and the second valve. 3. The cooling and heating system according to claim 1, wherein the control unit controls the first and second valves in the following manner: the compressor is stopped when the first heat exchanger is operating in a heating mode. When the first heat exchanger is operated in a heating mode, the refrigerant flows through the first parallel pipe; when the compressor is operated while the first heat exchanger is operating in a heating mode, the refrigerant flows through the second parallel pipe. 4. The cooling and heating system according to claim 1, wherein the dryer is arranged outside the area where the first heat exchanger performs cooling and heating, and is located at a branch of the first and second parallel pipelines point below. 5. The cooling and heating system according to claim 1, wherein the expansion mechanism is disposed above the dryer. 6. The cooling and heating system according to claim 1, wherein the first and second valves are a plurality of check valves. 7. The cooling and heating system according to claim 1, wherein the expansion mechanism is a capillary connected to both the first parallel pipe and the second parallel pipe. 8. The cooling and heating system according to claim 1, wherein the above-mentioned expansion mechanism comprises: a first capillary arranged in the same path as the above-mentioned first parallel pipe, and A second capillary arranged on the same path as the above-mentioned second parallel pipeline; The control unit performs switching of the first and second capillary tubes through the control of the first and second valves. 9. The cooling and heating system according to claim 1, wherein the refrigerant circulating in the cooling and heating system includes R600a, and the compressor is a reciprocating compressor for high temperature. 10. The cooling and heating system according to claim 1, wherein the capacity of the above-mentioned compressor is variable, and the above-mentioned control unit stabilizes the indoor temperature and lowers the temperature when the first heat exchanger works in a heating mode. The capacity of the above-mentioned compressors is basically continuous operation. 11. The cooling and heating system according to claim 1, further comprising a fan for cooling the compressor, and the control unit controls the compressor when the first heat exchanger operates in a cooling mode. During the operation, the fan is operated, and when the first heat exchanger is operated in a heating mode, the fan is stopped when the compression temperature is lower than a predetermined temperature. 12. The cooling and heating system according to claim 1, further comprising a cooling system for cooling a place different from the first heat exchanger. 13. The cooling and heating system according to claim 12, wherein the cooling system comprises: an evaporator, a condenser, a second compressor, a second expansion mechanism, and a combination of the second compressor and the second expansion mechanism , the above-mentioned evaporator and the above-mentioned condenser are connected to form a ring-shaped pipeline; The second heat exchanger is integrated with the condenser. 14. The cooling and heating system according to claim 13, characterized in that, the refrigerant pipeline of the above-mentioned condenser and the refrigerant pipeline of the above-mentioned second heat exchanger constitute a cascading evaporator heat exchange with finned tubes having two passages. device. 15. The cooling and heating system according to claim 14, wherein when the first heat exchanger is heating, the outlet pipe of the second heat exchanger is close to the inlet pipe of the cooling system. 16. The cooling and heating system according to claim 13, further comprising a fan for supplying air to the second heat exchanger and the condenser; The control unit may reduce the air volume of the fan when simultaneously operating the cooling by the cooling system and the heating by the first heat exchanger. 17. The cooling and heating system according to claim 1, further comprising an auxiliary heater for heating the first heat exchanger, and when the first heat exchanger is heated, the second heat exchanger There is also a condensation sensor at the inlet pipe; The control means stops the compressor and switches to heating by the auxiliary heater when the condensation sensor detects condensation for a certain period of time. 18. A refrigerator, characterized in that it comprises: The cooling and heating system described in claim 1; and The first accommodation chamber of the above-mentioned first heat exchanger is arranged inside. 19. The refrigerator according to claim 18, further comprising: a second storage chamber and a cooling system for cooling the second storage chamber. 20. A vending machine, characterized by comprising: The refrigerator according to claim 18; a collection department that collects money equivalent to the items stored in the above-mentioned holding room; and The goods stored in the said storage room are carried out to the carry-out part outside the said storage room according to the instruction|indication from the said cash receiving part. 21. A cooling and heating system, characterized by comprising: first condenser; first evaporator; first expansion mechanism; a dryer disposed between the first evaporator and the first expansion mechanism; first valve; compressor; Connecting the compressor, the first condenser, the drier, the first valve, the first expansion mechanism, and the first evaporator in the above order to form a ring-shaped first pipeline; second condenser; second expansion mechanism; second valve; second evaporator; connecting the above-mentioned compressor, the above-mentioned second condenser, the above-mentioned second expansion mechanism, the above-mentioned second valve and the above-mentioned second evaporator in the above order to form a ring-shaped second pipeline; a switching valve for selecting any one of the above-mentioned first conduit and the above-mentioned second conduit; and A control unit that controls at least the switching valve to switch the operating states of the first evaporator and the second condenser. 22. A refrigerator, characterized by comprising: The cooling and heating system described in claim 21; and The first accommodation chamber of the first evaporator and the second condenser is arranged inside. 23. The refrigerator according to claim 22, further comprising: a second storage chamber and a cooling system for cooling the second storage chamber. 24. A vending machine, characterized by comprising: The refrigerator according to claim 22; a collection department that collects money equivalent to the items stored in the above-mentioned holding room; and The goods stored in the said storage room are carried out to the carry-out part outside the said storage room according to the instruction|indication from the said cash receiving part.

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