JP2009110219A - vending machine - Google Patents

Abstract

The present invention relates to a vending machine that sells products such as canned beverages by cooling or heating them, and suppressing the increase in the amount of refrigerant circulation when the products are heated using a cooling and heating system, thereby improving the durability of the compressor. The purpose is to prevent the decrease.
SOLUTION: A resistor 30 is installed in a piping path that returns from an outdoor heat exchanger 13 to a compressor 12, and the evaporation temperature in the outdoor heat exchanger 13 is maintained to prevent frost formation and condensation. However, the suction pressure when heating the product storage chamber 10 can be suppressed, and the durability of the compressor 12 can be prevented from being lowered. In addition, when the product storage chamber 10 is heated, it is possible to suppress a decrease in the start-up characteristics caused by the refrigerant sleeping in the lubricating oil of the compressor 12, and when the product storage chamber 10 is cooled, The inflow of the high-temperature refrigerant to the indoor heat exchanger 11 can be suppressed, and an increase in the indoor cooling load can be suppressed.
[Selection] Figure 3

Description

  The present invention relates to a cooling and heating system that uses a latent heat generated when a refrigerant compressed by a compressor condenses in a vending machine that sells products such as canned beverages that are heated or cooled. The present invention relates to a vending machine having a system.

  In recent years, there has been an increasing demand for power consumption reduction for vending machines, and as a means for reducing power consumption, there is one that uses a waste heat generated by cooling or heat of the outside air to heat a storage room in which products are stored. It has been proposed (see, for example, Patent Document 1).

  Hereinafter, a conventional vending machine will be described with reference to the drawings.

  FIG. 6 is a refrigerant circuit diagram of a conventional vending machine, FIG. 7 is a timing chart showing the operation of the compressor and the on-off valve during heating in the conventional vending machine, and FIG. 8 is a cooling diagram in the conventional vending machine. It is a timing chart which shows the relationship between operation | movement of a compressor and an on-off valve.

  As shown in FIG. 6, the conventional vending machine includes evaporators 3 and 4 provided in the product storage chambers 1 and 2, a cooling compressor 5 and a condenser 6 disposed in a machine room below the product storage chamber. A cooling system comprising an expansion valve 7, an indoor heat exchanger 11 provided in the product storage chamber 10, a compressor 12 disposed in a machine room below the product storage chamber, and an outdoor heat exchanger 13. With a temperature system.

  Here, the product storage chambers 1 and 2 are used to cool and store products using a cooling system, and the product storage chamber 10 is used to store products cooled or heated using a cooling and heating system. is there. Further, the condenser 6 of the cooling system and the outdoor heat exchanger 13 of the cooling and heating system are integrally formed.

  The indoor heat exchanger 11 and the outdoor heat exchanger 13 in the cooling and heating system are connected by two parallel pipes, and one connecting pipe path has a cooling expansion valve 14 and a cooling check valve 15. A dryer 16 is installed in series, and a heating expansion valve 17 and a heating check valve 18 are installed in series on the other connection piping path.

  Here, the cooling check valve 15 is positive in the direction in which the refrigerant flows from the outdoor heat exchanger 13 to the indoor heat exchanger 11, and the heating check valve 18 is from the indoor heat exchanger 11 to the outdoor heat exchanger 13. The direction in which the refrigerant flows is assumed to be positive, and neither refrigerant flows in the opposite direction.

  An on-off valve 20 is connected to the connection pipe between the discharge side pipe of the compressor 12 and the outdoor heat exchanger 13, and an on-off valve 21 is connected to the connection pipe between the discharge side pipe of the compressor 12 and the indoor heat exchanger 11. An on-off valve 22 is installed on the connection pipe between the intake side pipe 12 and the indoor heat exchanger 11, and an on-off valve 23 is installed on the connection pipe between the intake side pipe of the compressor 12 and the outdoor heat exchanger 13. The flow path is switched according to the cooling and heating of the storage chamber 10.

  The operation of the conventional vending machine configured as described above will be described.

  In the cooling system for cooling the product storage chambers 1 and 2, the refrigerant compressed by the compressor 5 is condensed by exchanging heat with the outside air in the condenser 6, and then decompressed by the expansion valves 7 and 8, respectively. , 4. Then, after evaporating while exchanging heat with the room air in the product storage chambers 1 and 2, they are returned to the compressor 5. As a result, exhaust heat is released to the outside air while cooling the indoor air in the product storage chambers 1 and 2 to about 4 ° C.

  When the product storage chamber 10 is heated using a cooling and heating system, as shown in FIG. 7, the on-off valve 21 and the on-off valve 23 are opened regardless of whether the compressor 12 is on or off, and the on-off valve is opened. 20 and the on-off valve 22 are closed. The refrigerant compressed by the compressor 12 is condensed by exchanging heat with the indoor air in the product storage chamber 10 by the indoor heat exchanger 11, then decompressed by the heating expansion valve 17, and supplied to the outdoor heat exchanger 13. The Then, it evaporates while exchanging heat with the outside air, and then returns to the compressor 12. As a result, the indoor air of the product storage chamber 10 is heated to about 55 ° C. using the heat of the outside air and the exhaust heat from the condenser 6 of the cooling system.

When the product storage chamber 10 is cooled using the cooling and heating system, the on-off valve 20 and the on-off valve 22 are opened and the on-off valve 21 is opened regardless of whether the compressor 12 is on or off, as shown in FIG. And the on-off valve 23 is closed. The refrigerant compressed by the compressor 12 is condensed by exchanging heat with the outside air in the outdoor heat exchanger 13, then absorbed by the dryer 16, depressurized by the cooling expansion valve 14, and supplied to the indoor heat exchanger 11. Then, after evaporating while exchanging heat with the room air in the product storage room 10, it is refluxed to the compressor 12. As a result, exhaust heat is released to the outside air while cooling the indoor air of the product storage chamber 10 to about 4 ° C.
JP 2007-149045 A

  However, in the conventional configuration, when the product storage chamber 10 is heated using the cooling and heating system, there is a problem that the heating capacity becomes excessive and the durability of the compressor 12 is lowered. This is because, in a vending machine that does not have a dew condensation water drainage mechanism, it is necessary to bring the evaporation temperature close to the outside air temperature in order to suppress frost formation in the outdoor heat exchanger 13, and the intake gas density particularly at high outside air temperatures. This is because the amount of refrigerant circulation increases with the increase in the amount of refrigerant.

  As a result, the load on the compressor 12 becomes excessive, and the durability of the compressor 12 decreases. For example, when the product storage chamber 10 is cooled, the evaporation temperature is about −15 ° C., whereas when the product storage chamber 10 is heated, the evaporation temperature is about 10 ° C., and about 2.degree. The refrigerant circulation amount is 6 times.

  Usually, in order to solve this problem, the number of refrigerant circulations is suppressed by reducing the compressor rotation speed when the commodity storage chamber 10 is heated using a variable speed compressor. However, since variable speed compressors (inverter compressors) are expensive, a cheaper method is required to further disseminate vending machines that use the heat of the outside air and the exhaust heat of the cooling system to save energy. It is done.

  The present invention solves a conventional problem, and in contrast to cooling a product storage room using a cooling and heating system, refrigerant circulation in the case of heating while maintaining the evaporation temperature in an outdoor heat exchanger It aims at providing the vending machine which prevents the durable fall of a compressor by suppressing the increase in quantity.

  Further, in the conventional configuration, when the product storage chamber 10 is cooled or heated using the cooling and heating system, the refrigerant in the cooling and heating system is in a balanced state while the compressor 12 is stopped, and cooling or heating efficiency is increased. This causes a problem of lowering. This is because when the refrigerant in the cooling and heating system is in a balanced state during cooling, the high-temperature and high-pressure refrigerant staying in the outdoor heat exchanger 13 gradually moves to the indoor heat exchanger 11, thereby cooling the room. When the refrigerant in the cooling and heating system is in a balanced state when the load is increased and the heating is performed, the high-temperature and high-pressure refrigerant that stays in the indoor heat exchanger 11 stagnates in the lubricating oil of the compressor 12. This is because the amount of refrigerant at the time of startup is insufficient and the startup characteristics are degraded. Usually, in order to solve this problem, the entrance / exit of the heat exchanger in which the high-temperature and high-pressure refrigerant condenses and stays closed while the compressor 12 is stopped to prevent a balanced state. However, in order to close the entrance / exit of the heat exchanger, it is necessary to add an on-off valve or the like, and a cheaper method is required.

  The present invention solves the conventional problem, and when a product storage room is cooled or heated using a cooling and heating system, the compressor is stopped using an existing on-off valve that switches between cooling and heating. It aims at providing the vending machine which suppresses that the refrigerant | coolant in a cooling heating system becomes a balance state.

  In order to achieve the above object, the vending machine of the present invention is provided with a resistance means in a piping path connecting the outdoor heat exchanger and the suction side piping of the compressor, and cools the hot / cold switching chamber. The refrigerant discharged from the compressor can be a flow path that returns from the outdoor heat exchanger to the compressor via the indoor heat exchanger without passing through the resistance means, and when the hot / cold switching chamber is heated, the compressor The refrigerant flow switching mechanism is configured so that the refrigerant discharged from the refrigerant can be made into a flow path that returns from the indoor heat exchanger to the compressor through the resistance means after passing through the outdoor heat exchanger.

  As a result, when the product storage room is heated using the cooling and heating system, the suction pressure can be suppressed while maintaining the evaporation temperature in the outdoor heat exchanger, and the durability of the compressor is prevented from being lowered. be able to.

  In order to achieve the above object, the vending machine of the present invention closes a part of the on-off valve that constitutes the refrigerant flow path switching mechanism while the compressor is stopped, so that the refrigerant in the cooling and heating system is discharged. It is what suppresses becoming a balance state.

  As a result, when the product storage chamber is heated using the cooling and heating system, it is possible to suppress a decrease in the starting characteristics caused by the stagnation of the refrigerant in the lubricating oil of the compressor. When using and cooling a goods storage room, the inflow of the high temperature refrigerant | coolant to an indoor heat exchanger can be suppressed, and the increase in the indoor cooling load can be suppressed.

  The vending machine of the present invention maintains an evaporation temperature in the outdoor heat exchanger by using an inexpensive and simple configuration in which a resistance means is installed in a piping path that returns from the outdoor heat exchanger to the compressor. While preventing frost formation and condensation, it is possible to suppress the suction pressure when the product storage chamber is heated using the cooling and heating system, and it is possible to prevent a decrease in the durability of the compressor.

  In addition, the vending machine of the present invention has a simple operation of closing a part of the on-off valve that constitutes the refrigerant flow switching mechanism for switching between cooling and heating while the compressor is stopped. It is possible to suppress the refrigerant from being in a balanced state, and to suppress a decrease in cooling or heating efficiency.

  According to the first aspect of the present invention, a hot / cold switching chamber for storing a product in a cooled state or a warmed state, an indoor heat exchanger installed in the hot / cold switching chamber, and a product are stored. An outdoor heat exchanger installed outside the compartment, a compressor, resistance means provided in a piping path connecting the outdoor heat exchanger and the suction side piping of the compressor, and a refrigerant flow switching mechanism And the refrigerant flow switching mechanism cools the hot / cold switching chamber from the outdoor heat exchanger to the indoor heat exchanger without passing the refrigerant discharged from the compressor through the resistance means. When the hot / cold switching chamber is heated, the refrigerant discharged from the compressor passes through the outdoor heat exchanger from the indoor heat exchanger. Through the resistance means By using a flow path that returns to the compressor, when heating the product storage room using a cooling and heating system, while maintaining the evaporation temperature in the outdoor heat exchanger and preventing frost and condensation, The suction pressure can be suppressed, and a decrease in the durability of the compressor can be prevented.

  According to a second aspect of the present invention, in the first aspect of the present invention, when the compressor is a low-pressure compressor in the shell and the hot / cold switching chamber is heated, the compressor is stopped when the compressor is stopped. By blocking the flow path switching mechanism installed in the piping path connecting the suction side pipe and the outdoor heat exchanger, it is possible to suppress the deterioration of the starting characteristics caused by the refrigerant sleeping in the lubricating oil of the compressor. It is possible to suppress a decrease in heating efficiency.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, when the hot / cold switching chamber is heated, a pipe path connecting the suction side pipe of the compressor and the outdoor heat exchanger is provided. By opening the flow path switching mechanism installed in the pipe and the flow path switching mechanism installed in the piping path connecting the discharge side piping of the compressor and the outdoor heat exchanger immediately before starting the compressor, The compressor can be started by instantaneously balancing the low pressure, and it is possible to prevent the durability of the compressor from being reduced by applying an excessive load at the time of starting.

  According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, when the hot / cold switching chamber is cooled, the suction side piping of the compressor and the outdoor heat exchanger are connected. The flow path switching mechanism installed in the piping path to be opened is opened, and the flow path switching mechanism installed in the piping path connecting the suction side pipe of the compressor and the indoor heat exchanger is closed when the compressor is stopped. As a result, the high-temperature and high-pressure refrigerant staying in the outdoor heat exchanger is released into the compressor, the flow of the high-temperature refrigerant into the indoor heat exchanger is suppressed, and the cooling load is reduced due to an increase in the indoor cooling load. Can be suppressed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the same reference numerals are given to the same components as those of the conventional example, and detailed description thereof will be omitted. The present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a configuration diagram showing an internal configuration as viewed from the front of a main body of a vending machine according to Embodiment 1 of the present invention, and FIG. The longitudinal cross-sectional view at the time of seeing from the right is shown. FIG. 3 is a refrigerant circuit diagram of the vending machine according to the embodiment, FIG. 4 is a timing chart showing the relationship between the operation of the compressor and the on-off valve during heating in the vending machine according to the embodiment, and FIG. It is a timing chart which shows the relationship between the operation of the compressor at the time of cooling in the vending machine of embodiment, and an on-off valve.

  In FIG. 1, a vending machine 100 is for cooling or heating and selling canned beverage products, and a main body 101 made of a heat-insulating box that is open on the entire surface, and one side of which is pivotally supported by the main body 101. The outer door 102 is openable and closable. A sales outlet 103 is disposed at the lower part of the outer door 102.

  A product storage box 105 having a heat insulating door 104 on the front surface is formed in the main body 101 behind the outer door 102. As shown in FIG. 1, the inside of the product storage box 105 is divided into left and right three chambers by partition walls 106 and 107 filled with a vacuum heat insulating material, and the product storage chamber 1 (cooling) is placed on the left side of the partition wall 106. A dedicated storage room 2 is formed, and a product storage room 2 (cooling room) that can be switched by selecting either cooling or heating is formed at the center between the partition wall 106 and the partition wall 107. On the right side, there is formed a product storage room 10 (cooling greenhouse) that can be switched by selecting either cooling or heating.

  In each of the interiors 1, 2, and 10, a storage shelf 108 is suspended from the top of the product storage box 105, and products are stored inside. A carry-out device 109 for carrying out the selected merchandise is disposed below the storage shelf 108, and the merchandise is dropped downward one by one. A chute 110 inclined toward the sales outlet 103 is arranged below the carry-out device 109, and the product discharged from each storage shelf 108 falls on the chute 110 and rolls to the sales outlet 103. It will be guided.

  Below the chute 110, a cooling chamber 111 and cooling chambers 112, 113 are provided corresponding to the product storage chambers 1, 2, 10 respectively. The cooling chamber 111 is provided with an evaporator 3 that cools the product storage chamber 1, and the cooling greenhouse 112 is provided with an evaporator 4 and an electric heater 114 that is energized during heating. Further, the cooling greenhouse 113 includes an indoor heat exchanger 11 and an electric heater 115 that can be energized as an auxiliary to the indoor heat exchanger 11 during heating. Each chamber 1, 2 and 10 has an in-compartment fan 118, forcibly ventilating to circulate the inside of the chamber, and an in-compartment sensor (not shown) provided in each of the chambers 1, 2, and 10 is provided. The inside is controlled to an appropriate temperature.

  A machine room 117 defined by a partition wall 116 provided at the lower part of the commodity storage 105 is formed below the main body 101.

  Next, the configuration inside the machine room 117 will be described.

  As shown in FIGS. 1 to 3, the vending machine according to the present embodiment includes an evaporator 3, 4 provided in the product storage chambers 1, 2 and a machine chamber 117 below the product storage chambers 1, 2, 10. In the cooling system which connected the compressor 5 for cooling, the condenser 6, and the expansion valves 7 and 8 which were arrange | positioned, the indoor heat exchanger 11 provided in the goods storage room 10, and the machine room 117 below the goods storage 105 The compressor 12 and the outdoor heat exchanger 13 which are arrange | positioned are provided with the cooling and heating system which connected. The cooling compressor 5 and the compressor 12 are constant speed compressors driven at a commercial power supply frequency. As the refrigerant, a flammable refrigerant such as isobutane or an HFC refrigerant such as R134A is used.

  Here, the product storage chambers 1 and 2 store products by cooling them using a cooling system, and the product storage chamber 10 stores products after cooling or heating products using a cooling and heating system. Is. Further, the condenser 6 of the cooling system and the outdoor heat exchanger 13 of the cooling and heating system are integrally formed.

  The indoor heat exchanger 11 and the outdoor heat exchanger 13 in the cooling and heating system include a heating connection pipe 120 that flows from the indoor heat exchanger 11 to the outdoor heat exchanger 13 during indoor heating, and an indoor heat from the outdoor heat exchanger 13. It is connected by two parallel pipes connected to the cooling connection pipe 121 flowing to the exchanger 11, and the cooling connection pipe 121 has a cooling expansion valve 14 (may be a capillary tube) and a cooling check valve 15. A dryer 16 is installed in series, and a heating expansion valve 17 (may be a capillary tube) and a heating check valve 18 are installed in series on the path of the heating connection pipe 120.

  Here, the cooling check valve 15 is positive in the direction in which the refrigerant flows from the outdoor heat exchanger 13 to the indoor heat exchanger 11, and the heating check valve 18 is from the indoor heat exchanger 11 to the outdoor heat exchanger 13. The direction in which the refrigerant flows is assumed to be positive, and neither refrigerant flows in the opposite direction.

  An on-off valve 20 serving as a flow path switching mechanism is connected to the connection pipe between the discharge side pipe of the compressor 12 and the outdoor heat exchanger 13, and the connection pipe between the discharge side pipe of the compressor 12 and the indoor heat exchanger 11. Has an on-off valve 21, and the on-off valve 20 and the on-off valve 21 are connected in parallel to the discharge side piping of the compressor 12. An on-off valve 22 is connected to the connection pipe between the suction side pipe of the compressor 12 and the indoor heat exchanger 11, and an on-off valve 23 and a resistor 30 are connected to the connection pipe between the suction side pipe of the compressor 12 and the outdoor heat exchanger 13. Are connected in parallel, and the on-off valve 22 and the on-off valve 23 are connected in parallel to the suction side piping of the compressor 12 to switch the flow path in accordance with cooling and heating of the product storage chamber 10. The open / close valves 21 to 23 are flow path switching mechanisms similar to the open / close valve 20.

  Here, the resistor 30 is formed of a small diameter tube having an inner diameter of 2 mm and a length of about 600 mm, and the flow rate of the refrigerant gas passing through can be kept substantially constant when the flow velocity of the refrigerant in the small diameter tube reaches near the sonic speed. . Moreover, the pressure drop amount of the resistor 30 can be arbitrarily set by adjusting the inner diameter and the length of the small-diameter pipe according to the refrigerant pressure of the outdoor heat exchanger 13 and the volume flow rate of the compressor 12.

  The vending machine of the present embodiment is installed in a hot / cold switching chamber (product storage chamber 10) for storing products in a cooled state or in a heated state, and a hot / cold switching chamber (product storage chamber 10). Indoor heat exchange from the indoor heat exchanger 11, the outdoor heat exchanger 13 installed outside the compartment for storing products (the machine room 117 below the product storage 105), the compressor 12, and the outdoor heat exchanger 13 The cooling expansion valve 14, the cooling check valve 15, and the dryer 16 that are installed in the cooling connection pipe 121 that flows to the vessel 11, and the heating connection pipe 120 that flows from the indoor heat exchanger 11 to the outdoor heat exchanger 13 are installed. A heating expansion valve 17, a heating check valve 18, resistance means (resistor 30) provided in a piping path connecting the outdoor heat exchanger 13 and the suction side piping of the compressor 12, Refrigerant flow path switching mechanism (open / close valves 20 to 23) Equipped with a.

  When the refrigerant flow switching mechanism (open / close valves 20 to 23) cools the hot / cold switching chamber (product storage chamber 10), the refrigerant discharged from the compressor 12 is converted into the open / close valve 20 and the outdoor heat. The on-off valves 20 and 22 are opened so as to return to the compressor 12 via the exchanger 13, the dryer 16, the cooling check valve 15, the cooling expansion valve 14, the indoor heat exchanger 11 and the on-off valve 22 in this order. When the on / off valves 21 and 23 are closed and the hot / cold switching chamber (product storage chamber 10) is heated, the refrigerant discharged from the compressor 12 is transferred to the on / off valve 21 and the indoor heat exchanger 11. , The expansion valve 17 for heating, the check valve 18 for heating, the outdoor heat exchanger 13, the resistance means (resistor 30), and the on-off valve 23 in order to return to the compressor 12. 22 are closed, and the open / close valves 21 and 23 are open. It is.

  The operation of the vending machine of the present embodiment configured as described above will be described.

  In the cooling system for cooling the product storage chambers 1 and 2, the refrigerant compressed by the compressor 5 is condensed by exchanging heat with the outside air in the condenser 6, and then decompressed by the expansion valves 7 and 8, respectively. , 4. Then, after evaporating while exchanging heat with the room air in the product storage chambers 1 and 2, they are returned to the compressor 5. As a result, exhaust heat is released to the outside air while cooling the indoor air in the product storage chambers 1 and 2 to about 4 ° C.

  Further, when the product storage chamber 10 is heated using the cooling and heating system, as shown in FIG. 4, the open / close valve 21 and the open / close valve 23 are opened and the open / close valve 20 is opened / closed during operation of the compressor 12. The valve 22 is closed.

  Thus, during the operation of the compressor 12, the refrigerant compressed by the compressor 12 passes through the on-off valve 21 and is condensed by exchanging heat with the indoor air in the product storage chamber 10 by the indoor heat exchanger 11. The pressure is reduced by the warm expansion valve 17 and supplied to the outdoor heat exchanger 13.

  Then, after evaporating while exchanging heat with the outside air in the outdoor heat exchanger 13, the pressure is reduced by the resistor 30, and then returned to the compressor 12 through the on-off valve 23.

  Therefore, the suction pressure of the compressor 12 is reduced to −10 ° C. or less at the saturation temperature while maintaining the evaporation pressure (about + 5 ° C. at the saturation temperature) at which the outdoor heat exchanger 13 is not condensed or frosted by the resistor 30. A significant increase in heating capability can be suppressed. Further, by reducing the suction pressure, it is possible to suppress the stress of the suction valve inside the compressor 12 and improve the reliability of the compressor.

  Further, all the on-off valves 20 to 23 are closed while the compressor 12 is stopped, and the on-off valve 20 and the on-off valve 23 are opened immediately before the compressor 12 is started. Thus, when the compressor 12 is stopped, the refrigerant circulating in the piping can be prevented from returning to the compressor 12 by closing all the on-off valves 20 to 23, and the shell of the compressor 12 is operating. Therefore, the refrigerant can be prevented from dissolving in the lubricating oil in the compressor 12, the temperature drop of the compressor 12 during the next start-up is suppressed, and the refrigerant stagnates in the lubricating oil. It is possible to suppress the deterioration of the starting characteristic that occurs.

  Further, by opening the on-off valve 20 and the on-off valve 23 immediately before starting, the discharge side and the suction side of the compressor 12 are directly connected via the outdoor heat exchanger 13 and the resistor 30, and the pressure is balanced. The compressor 12 can be started immediately without waiting for the high / low pressure balance at the start-up. Moreover, since the indoor heat exchanger 11 is directly connected through the expansion valve 17 by opening the on-off valve 20, it is possible to prevent the refrigerant in the indoor heat exchanger 11 from returning to the compressor 12 as much as possible when stopped. Heat loss in the room while the compressor 12 is stopped can be prevented. As a result, an increase in the indoor heating load can be suppressed, the load on the compressor 12 at startup can be reduced, and the amount of power consumption can be reduced.

  When the compressor 12 is started, the on-off valve 20 is closed, the on-off valve 23 is kept open, the on-off valve 21 is opened, and the heating operation is performed again.

  In this way, the indoor air in the product storage chamber 10 is heated to about 55 ° C. using the heat of the outside air and the exhaust heat from the condenser 6 of the cooling system, and the outdoor heat exchanger is operated during the operation of the compressor 12. The evaporation temperature of 13 is maintained at a temperature about 5 ° C. lower than the outside air temperature (for example, about 10 ° C. at the outside air temperature of 15 ° C.), and becomes a pressure corresponding to the saturation temperature of about −10 ° C. downstream of the resistor 30. . Further, when the compressor 12 is stopped, the refrigerant does not dissolve in the lubricating oil (not shown) stored in the shell, and there is not enough refrigerant to circulate in the cooling and heating system immediately after the compressor 12 is started. And it can prevent that a heating capability falls.

  Here, it is desirable to set the pressure drop amount in the resistor 30 at the outside air temperature of 15 ° C. to 15 to 25 ° C. at the refrigerant saturation temperature. By adjusting the pressure drop in this range, it is possible to prevent the suction pressure of the compressor 12 from becoming excessive while suppressing frost formation and dew condensation in the outdoor heat exchanger 13.

  Further, by using the resistor 30 made of a small diameter tube, when the evaporation temperature of the outdoor heat exchanger 13 becomes lower as the outside air temperature decreases, the pressure drop amount of the resistor 30 decreases. Since it can suppress that the suction pressure of the compressor 12 falls more than needed at low external temperature, and the compression ratio of the compressor 12 can be suppressed, reliability can be ensured.

  On the other hand, when the product storage chamber 10 is cooled using the cooling and heating system, as shown in FIG. 3, the refrigerant compressed by the compressor 12 passes through the on-off valve 20 and exchanges heat with the outside air using the outdoor heat exchanger 13. After being condensed, the moisture is absorbed by the dryer 16, the pressure is reduced by the cooling expansion valve 14, and then supplied to the indoor heat exchanger 11. Then, after evaporating while exchanging heat with the room air in the product storage chamber 10, the cooling cycle returns to the compressor 12 through the on-off valve 22.

  Thus, during operation of the compressor 12, the refrigerant compressed by the compressor 12 passes through the on-off valve 20, exchanges heat with the outside air in the outdoor heat exchanger 13, condenses, and then absorbs moisture in the dryer 16 and expands for cooling. The pressure is reduced by the valve 14 and supplied to the indoor heat exchanger 11. Then, after evaporating while exchanging heat with the room air in the product storage chamber 10, the vapor passes through the on-off valve 22 and returns to the compressor 12.

  As a result, while cooling the room air in the product storage room 10 to about 4 ° C., exhaust heat is released to the outside air, and the evaporation temperature of the indoor heat exchanger 11 is about 20 ° C. lower than the room air temperature in the product storage room 10. The temperature is maintained (eg, room air is about -16 ° C at 4 ° C).

  As shown in FIG. 5, when the compressor 12 is stopped, the on-off valve 20 is kept open, the on-off valve 23 is opened, and the on-off valve 21 and the on-off valve 22 are closed.

  As a result, while the compressor 12 is stopped, the high-temperature refrigerant in the outdoor heat exchanger 13 is opened in the shell of the compressor 12, thereby compressing the refrigerant in the outdoor heat exchanger 13 without passing through the indoor heat exchanger 11. The pressure can be reduced by opening it to the machine, and the pressures of the outdoor heat exchanger 13 and the indoor heat exchanger 11 are quickly balanced.

  As a result, while the compressor 12 is stopped, the high-temperature refrigerant in the outdoor heat exchanger 13 can be suppressed from flowing into the indoor heat exchanger 11 and the increase in the indoor cooling load can be suppressed.

  Then, immediately after the compressor 12 is started, the on-off valve 22 is opened, the on-off valve 23 is closed, and the compressor 12 is operated.

  Further, as shown in FIG. 5, as the operation of the on-off valves 22 and 23 immediately after the compressor 12 is started, the on-off valve 22 is opened and the on-off valve 23 is closed with a slight delay from the operation of the compressor 12. Also good. Thus, if the opening and closing operations are performed simultaneously with the start of the compressor 12, it is possible to suppress the occurrence of differential pressure in the high / low pressure balance, and the load on the compressor 12 at the start can be reduced.

  As described above, in the vending machine according to Embodiment 1 of the present invention, when the product storage room 10 is heated, the evaporation temperature in the outdoor heat exchanger 13 is maintained near the outside air temperature to form frost or condensation. Thus, the suction pressure of the compressor 12 can be suppressed to substantially the same level as that in the cooling operation, and the durability of the compressor 12 can be prevented from being lowered due to an excessive increase in the suction pressure.

  Further, when the product storage chamber 10 is heated using the cooling and heating system, it is possible to suppress a decrease in the starting characteristics caused by the refrigerant stagnating in the lubricating oil of the compressor 12, and the cooling and heating system. When the product storage chamber 10 is cooled using the refrigeration, the inflow of the high-temperature refrigerant into the indoor heat exchanger 11 can be suppressed to suppress an increase in the indoor cooling load.

  Further, the cooling and heating system can be controlled by the constant speed compressor 12 as described above, and energy saving can be realized with an inexpensive structure.

  As described above, the vending machine according to the present invention uses an inexpensive and simple configuration in which a resistor is installed in a piping path that returns from the outdoor heat exchanger to the compressor. Maintaining the evaporating temperature and preventing frost and condensation while suppressing the suction pressure when heating the product storage room using the cooling and heating system, and preventing the compressor from degrading in durability Therefore, it can be applied to a compressor that is heated in a showcase that switches between hot beverage and cold beverage for storage.

  In addition, the vending machine of the present invention suppresses the refrigerant in the cooling and heating system from being balanced by a simple operation of closing a part of the on-off valve that switches between cooling and heating while the compressor is stopped. In addition, since a decrease in cooling or heating efficiency can be suppressed, the present invention can also be applied to applications requiring energy saving during heating and cooling operations such as a showcase that switches between hot drinks and cold drinks for storage.

The block diagram which shows the internal structure of the main body of the vending machine in Embodiment 1 of this invention Longitudinal sectional view when the vending machine of the embodiment is cut vertically from side to side Refrigerant circuit diagram of vending machine in the embodiment Timing chart showing the relationship between the operation of the compressor and the on-off valve during heating in the vending machine of the embodiment Timing chart showing the relationship between the operation of the compressor and the on-off valve during cooling in the vending machine of the embodiment Refrigerant circuit diagram of a conventional vending machine Timing chart showing the operation of the compressor and on-off valve during heating in a conventional vending machine Timing chart showing the relationship between compressor and on-off valve operation during cooling in a conventional vending machine

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Commodity storage room 11 Indoor heat exchanger 12 Compressor 13 Outdoor heat exchanger 20 On-off valve 21 On-off valve 22 On-off valve 23 On-off valve 30 Resistor

Claims (4)

A hot / cold switching chamber for storing products in a cooled or warmed state, an indoor heat exchanger installed in the hot / cold switching chamber, and an outdoor heat exchanger installed outside the compartment for storing products A compressor, resistance means provided in a piping path connecting the outdoor heat exchanger and the suction side piping of the compressor, and a refrigerant flow path switching mechanism,
The refrigerant flow switching mechanism, when cooling the hot / cold switching chamber, passes the refrigerant discharged from the compressor from the outdoor heat exchanger via the indoor heat exchanger without passing through the resistance means. In the case where the hot / cold switching chamber is heated by using a flow path returning to the compressor, the resistance means is provided after the refrigerant discharged from the compressor passes through the outdoor heat exchanger from the indoor heat exchanger. A vending machine characterized by having a flow path that passes back to the compressor.   When the compressor is a low-pressure compressor in the shell and the hot / cold switching chamber is heated, it is installed in the piping path that connects the suction side piping of the compressor and the outdoor heat exchanger when the compressor is stopped. The vending machine according to claim 1, wherein the flow path switching mechanism is closed.   When heating the hot / cold switching chamber, a flow path switching mechanism installed in a piping path connecting the suction side piping of the compressor and the outdoor heat exchanger, a discharge side piping of the compressor, and the outdoor side The vending machine according to claim 1 or 2, wherein a flow path switching mechanism installed in a piping path connecting the heat exchanger is opened immediately before starting the compressor.   When cooling the hot / cold switching chamber, a flow path switching mechanism installed in a piping path connecting the suction side piping of the compressor and the outdoor heat exchanger is opened, and the suction side piping of the compressor and the The vending machine according to any one of claims 1 to 3, wherein a flow path switching mechanism installed in a piping path connecting an indoor heat exchanger is closed when the compressor is stopped.