JP2010043757A - Refrigerant circuit device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a refrigerant circuit device reducing power consumption by shortening a time necessary for pump-down while reducing cost. <P>SOLUTION: The refrigerant circuit device includes a main refrigerant circuit 20 composed of an evaporator 24, a compressor 21 for sucking and compressing a refrigerant evaporated by the evaporator 24, a condenser 22 for condensing the refrigerant from the compressor 21, and an expanding mechanism 23 for expanding the refrigerant from the condenser 22, an inside heat exchanger 31 for condensing the refrigerant introduced through a branching introduction refrigerant piping 33 for branching and introducing the refrigerant compressed by the compressor 21, and a sub-refrigerant circuit 30 composed of return refrigerant piping 37 for returning the refrigerant passing the inside heat exchanger 31 to the main refrigerant circuit 20, the expanding mechanism 23 is constituted by arranging a plurality of capillary tubes 231, 232 in series, and the return refrigerant piping 37 supplies the refrigerant to a joint part 254 between the capillary tubes 231, 232 adjacent to each other. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a refrigerant circuit device, and more particularly to a refrigerant circuit device applied to, for example, a vending machine.

  2. Description of the Related Art Conventionally, as a refrigerant circuit device applied to, for example, a vending machine, one having a main refrigerant circuit and a sub refrigerant circuit is known. The main refrigerant circuit has an annular shape in which an evaporator, a compressor, a condenser, and an expansion mechanism are sequentially connected by a refrigerant pipe.

  The evaporator is disposed inside the commodity storage of the vending machine. This evaporator cools the internal air of the product storage box as the passing refrigerant evaporates.

  The compressor is disposed inside the vending machine main body and outside the product storage, for example, in the machine room. The compressor sucks the refrigerant evaporated by the evaporator, compresses the sucked refrigerant and compresses it at high temperature and high pressure. In this state, the liquid is discharged.

  Like the compressor, the condenser is disposed in a place (machine room or the like) in the vending machine main body and outside the commodity storage. This condenser heats the ambient air, that is, radiates heat to the ambient air, as the passing refrigerant condenses.

  Like the compressor and the condenser, the expansion mechanism is disposed in a place (machine room or the like) inside the vending machine main body and outside the commodity storage. This expansion mechanism is for adiabatically expanding the refrigerant condensed in the condenser by reducing the pressure.

  In such a main refrigerant circuit, the refrigerant compressed by the compressor is condensed by the condenser, and the condensed refrigerant is adiabatically expanded by the expansion mechanism and evaporated by the evaporator. The refrigerant evaporated in the evaporator is sucked by the compressor, compressed again, and circulated. As a result, the internal air of the commodity storage box in which the evaporator is disposed is cooled.

  The sub-refrigerant circuit has an in-compartment heat exchanger that is disposed inside the vending machine body and inside the product storage that is to be heated. In this sub refrigerant circuit, the refrigerant compressed by the compressor is branched and introduced into the internal heat exchanger, and the internal air of the product storage is heated by radiating heat from the internal heat exchanger. The refrigerant radiated by the internal heat exchanger is returned to the main refrigerant circuit. In such a sub refrigerant circuit, an electromagnetic valve is provided in a pipe for introducing refrigerant from the main refrigerant circuit, and when the electromagnetic valve is opened, the internal air of the product storage box in which the internal heat exchanger is disposed is supplied. I try to heat it. That is, when cooling the internal air of the product storage, the electromagnetic valve is closed.

  In such a refrigerant circuit device, a temperature expansion valve or an electronic expansion valve is generally used as an expansion mechanism. However, these expansion valves are expensive, so that the cost can be reduced. Some use capillary tubes (see, for example, Patent Document 1).

JP 2002-130896 A

  By the way, in the refrigerant circuit device as described above, when all the commodity storage is cooled, the electromagnetic valve is closed and the internal heat exchanger of the sub refrigerant circuit is stopped. If it does so, a part of refrigerant | coolant stagnates also in this internal heat exchanger, and there exists a possibility that the circulation amount of the refrigerant | coolant in a main refrigerant circuit may run short.

  In order to avoid such a situation where the refrigerant circulation amount is insufficient, a pump-down operation is generally performed. The pump down operation is an operation in which the refrigerant in the refrigerant circuit is sucked and extracted by the compressor.

  However, when a capillary tube is used as an expansion mechanism as in the refrigerant circuit device as described above, the resistance in the capillary tube is large, and the time required for the pump-down operation is lengthened, resulting in an increase in power consumption. There was a problem.

  In view of the above circumstances, an object of the present invention is to provide a refrigerant circuit device capable of reducing the time required for pumping down and reducing power consumption while reducing costs.

  In order to achieve the above object, a refrigerant circuit device according to claim 1 of the present invention is provided in an interior of a chamber to be cooled, and evaporates the supplied refrigerant to cool the internal atmosphere of the chamber. A compressor that sucks and compresses the refrigerant evaporated by the evaporator, a condenser that introduces and condenses the refrigerant compressed by the compressor, and expands the refrigerant condensed by the condenser A main refrigerant circuit configured by sequentially connecting an expansion mechanism to be supplied to the evaporator through a refrigerant pipe, a branch introduction path for branching and introducing the refrigerant compressed by the compressor, and a heating target. An indoor heat exchanger that condenses the refrigerant introduced through the branch introduction path and heats the internal atmosphere of the chamber, and the refrigerant that has passed through the indoor heat exchanger is disposed in the main refrigerant circuit. A sub-refrigerant having a return path for returning to In the refrigerant circuit device including the passage, the expansion mechanism is configured by arranging a plurality of capillary tubes in a serial manner, and the return path is adjacent to the capillary tubes constituting the expansion mechanism. The refrigerant is supplied to the junction between the two and returned to the main refrigerant circuit.

  The refrigerant circuit device according to claim 2 of the present invention is the refrigerant circuit device according to claim 1, wherein the sub refrigerant circuit is disposed outside the chamber to be heated and condensed by the indoor heat exchanger. An outdoor heat exchanger that introduces refrigerant and dissipates heat to ambient air is provided, and the return path supplies the refrigerant that has passed through the outdoor heat exchanger to the junction and returns it to the main refrigerant circuit. .

  A refrigerant circuit device according to a third aspect of the present invention is the refrigerant circuit device according to the first or second aspect, wherein the refrigerant circuit device branches in the middle of a path from the indoor heat exchanger to the junction, and the expansion mechanism Arranged in such a way that it joins in the middle of the path to the evaporator, and is provided in the bypass path for sending the introduced refrigerant to the main refrigerant circuit and in the bypass path, and the refrigerant passes through the bypass path by opening and closing. And a bypass valve that permits or restricts the operation.

  A refrigerant circuit device according to a fourth aspect of the present invention is the refrigerant circuit device according to any one of the first to third aspects, wherein the refrigerant circuit device branches off in the middle of a path from the condenser to the expansion mechanism. Arranged in a manner that merges in the middle of the path to the evaporator, and is arranged in another bypass path that introduces the refrigerant condensed in the condenser and sends it to the evaporator, and in the other bypass path And another bypass valve that allows or restricts the refrigerant from passing through the other bypass path by opening and closing.

  According to the refrigerant circuit device of the present invention, an expansion mechanism is configured by arranging a plurality of capillary tubes in series, and the refrigerant whose return refrigerant path has passed through the indoor heat exchanger is disposed between adjacent capillary tubes. Since the refrigerant is supplied to the junction and returned to the main refrigerant circuit, it is not necessary to pass all the capillary tubes constituting the expansion mechanism when the refrigerant in the sub refrigerant circuit is sucked. As a result, the resistance in the capillary tube can be relatively reduced, thereby shortening the time required for pumping down, and as a result, the power consumption can be reduced. In addition, since the capillary tube is used, the cost can be reduced as compared with the use of an electronic expansion valve or the like. Therefore, it is possible to reduce the time required for pumping down and reduce power consumption while reducing the cost.

  Exemplary embodiments of a refrigerant circuit device according to the present invention will be explained below in detail with reference to the accompanying drawings.

<Embodiment 1>
FIG. 1 is a cross-sectional view showing a case where an internal structure of a vending machine to which the refrigerant circuit device according to Embodiment 1 of the present invention is applied is viewed from the front. The vending machine illustrated here includes a main body cabinet 1.

  The main body cabinet 1 has a rectangular shape with an open front surface. The main body cabinet 1 is provided with three independent commodity containers 3 partitioned by, for example, two heat insulating partition plates 2 in a side-by-side manner. This product storage 3 is for storing products such as canned beverages and beverages containing plastic bottles while maintaining a desired temperature, and has a heat insulating structure.

  FIG. 2 shows the internal structure of the vending machine shown in FIG. 1, and is a cross-sectional side view of the right commodity storage. Here, although the internal structure of the right product storage 3 (hereinafter also referred to as the right storage 3a) is shown, the central product storage 3 (hereinafter also referred to as the intermediate storage 3b) and the left product storage 3 are shown. The internal structure (hereinafter also referred to as the left warehouse 3c as appropriate) has substantially the same configuration as the right warehouse 3a. In the present specification, the right side indicates the right side when the vending machine is viewed from the front, and the left side indicates the left side when the vending machine is viewed from the front.

  As shown in FIG. 2, an outer door 4 and an inner door 5 are provided on the front surface of the main body cabinet 1. The outer door 4 is for opening and closing the front opening of the main body cabinet 1, and the inner door 5 is for opening and closing the front surface of the commodity storage 3. The inner door 5 is divided into upper and lower parts, and the upper door 5a opens and closes when a product is replenished.

  The commodity storage 3 is provided with a commodity storage rack 6, a carry-out mechanism 7 and a carry-out shooter 8. The commodity storage rack 6 is for storing commodities in a manner arranged in the vertical direction. The carry-out mechanism 7 is provided at the lower part of the product storage rack 6 and is used to carry out the products at the bottom of the product group stored in the product storage rack 6 one by one. The carry-out shooter 8 is for guiding the product carried out from the carry-out mechanism 7 to the product take-out port 4 a provided in the outer door 4.

  FIG. 3 is a conceptual diagram conceptually showing a refrigerant circuit device applied to the vending machine shown in FIGS. 1 and 2. The refrigerant circuit device 10 exemplified here includes a main refrigerant circuit 20 and a sub refrigerant circuit 30.

  The main refrigerant circuit 20 is configured by sequentially connecting a compressor 21, a condenser 22, an expansion mechanism 23, and an evaporator 24 through a refrigerant pipe 25, and a refrigerant is enclosed therein.

  The compressor 21 is disposed in the machine room 9 as shown in FIG. The machine room 9 is a room inside the main body cabinet 1, partitioned from the product storage 3 and below the product storage 3. The compressor 21 sucks the refrigerant through the suction port, compresses the sucked refrigerant to be in a high-temperature and high-pressure state (high-temperature and high-pressure refrigerant), and discharges it from the discharge port.

  As shown in FIG. 2, the condenser 22 is disposed in the machine room 9 similarly to the compressor 21. The condenser 22 condenses the refrigerant that passes therethrough. More specifically, the refrigerant compressed by the compressor 21 and discharged from the discharge port and sent out through the refrigerant pipe 25 is condensed by exchanging heat with ambient air.

  The refrigerant pipe 25 connecting the condenser 22 and the compressor 21 is provided with a high-pressure side electromagnetic valve 261. The high-pressure side electromagnetic valve 261 is a valve body that can be opened and closed. When the open command is given, the high-pressure side solenoid valve 261 opens and allows the refrigerant to pass therethrough. It regulates the passage of 2 and 3, reference symbol F <b> 1 is an external fan that is disposed in the vicinity of the condenser 22. This outside blower fan F <b> 1 blows outside air around the condenser 22.

  As shown in FIG. 2, the expansion mechanism 23 is disposed in the machine room 9 similarly to the compressor 21 and the condenser 22. The expansion mechanism 23 is configured by arranging a plurality (two in the illustrated example) of capillary tubes 231 and 232 in a serial manner, and adiabatically expands the refrigerant passing through by reducing the pressure. Reference numeral 262 in FIG. 3 is a check valve.

  A plurality (three in the illustrated example) of the evaporators 24 are provided, and are disposed inside each commodity storage 3. Here, the refrigerant pipe 25 connecting the evaporator 24 and the expansion mechanism 23 (capillary tube 232) branches into three at a branch point 251 in the middle, and the evaporator 24 disposed in the right warehouse 3a. (Hereinafter also referred to as the first evaporator 24a) on the inlet side of the evaporator 24 (hereinafter also referred to as the second evaporator 24b) disposed in the inner cabinet 3b on the inlet side of the left evaporator 3c. Each is connected to an inlet side of the provided evaporator 24 (hereinafter also referred to as a third evaporator 24c).

  In the refrigerant pipe 25, low-pressure side solenoid valves 263, 264, and 265 are provided on the way from the branch point 251 to each of the first evaporator 24a to the third evaporator 24c. The low-pressure side solenoid valves 263, 264, and 265 are openable and closable valve elements that open when a command to open is given and allow the refrigerant to pass, but close when a command to close is given. Thus, the passage of the refrigerant is restricted.

  The refrigerant pipes 25 connected to the outlet side of these evaporators 24 are merged at a midway junction 252 and connected to the compressor 21 via the accumulator 27. Here, the accumulator 27 is for storing the liquid-phase refrigerant and allowing the gas-phase refrigerant to pass through when the refrigerant passing therethrough is a gas-liquid mixed refrigerant.

  The sub refrigerant circuit 30 is a circuit formed by branching from the main refrigerant circuit 20 and includes an internal heat exchanger 31 and an external heat exchanger 32.

  A plurality (two in the illustrated example) of the internal heat exchangers 31 are provided, one of which is disposed inside the middle warehouse 3b and the other is disposed inside the left warehouse 3c. These internal heat exchangers 31 exchange heat with the internal air (internal atmosphere) of the product storage 3 (the central storage 3b and the left storage 3c) in which the passing refrigerant is disposed, that is, the refrigerant and the target that pass therethrough. Heat exchange is performed with the internal air of the product storage 3 (the central storage 3b and the left storage 3c). These internal heat exchangers 31 are connected to the compressor 21 via a common branch introduction refrigerant pipe 33.

  The branch introduction refrigerant pipe 33 introduces a refrigerant (high pressure refrigerant) branched from the high pressure side branch point 253 in the middle of the refrigerant pipe 25 connecting the compressor 21 and the condenser 22 and compressed by the compressor 21. It is. The branch introduction refrigerant pipe 33 is further branched in the middle, and one side is connected to the internal heat exchanger 31 of the internal storage 3b and the other is connected to the internal heat exchanger 31 of the left storage 3c.

  In the branch introduction refrigerant pipe 33, branch solenoid valves 341 and 342 are provided on the downstream side of the branch point, respectively. The branch solenoid valves 341 and 342 are valve bodies that can be opened and closed. When the opening command is given, the branching electromagnetic valves 341 and 342 are opened to allow the refrigerant to pass therethrough. It regulates the passage of

  In other words, each of the internal heat exchangers 31 is supplied with the refrigerant compressed by the compressor 21 through the branch introduction refrigerant pipe 33, and therefore condenses the refrigerant that passes therethrough to be the target product storage 3 (inside The internal air of the storage 3b and the left storage 3c) is heated.

  Here, an internal blower fan is disposed inside each commodity storage 3. The internal blower fan (hereinafter also referred to as the right internal blower fan F2) inside the right warehouse 3a is disposed in the vicinity of the first evaporator 24a and is cooled by the first evaporator 24a. Is circulated inside the right warehouse 3a. An internal blower fan (hereinafter also referred to as an internal blower fan F3) inside the internal warehouse 3b is disposed in the vicinity of the second evaporator 24b and the internal heat exchanger 31, and the second evaporator The internal air cooled by 24b or the internal air heated by the internal heat exchanger 31 is circulated inside the internal storage 3b. The internal blower fan (hereinafter also referred to as the left internal blower fan F4) inside the left warehouse 3c is disposed in the vicinity of the third evaporator 24c and the internal heat exchanger 31, and the third evaporator The internal air cooled by 24c or the internal air heated by the internal heat exchanger 31 is circulated inside the left storage 3c.

  Refrigerant pipes 35 are respectively connected to the outlet sides of these internal heat exchangers 31, and these refrigerant pipes 35 are joined on the way and connected to the inlet side of the external heat exchanger 32. Here, reference numerals 361 and 362 in FIG. 3 denote check valves.

  The external heat exchanger 32 is disposed in the machine room 9 similarly to the compressor 21. The external heat exchanger 32 exchanges heat between the passing refrigerant and ambient air, that is, heat exchange between passing air and ambient air (for example, outside air). More specifically, the external heat exchanger 32 radiates the refrigerant supplied from the internal heat exchanger 31 through the refrigerant pipe 35, that is, the refrigerant condensed in the internal heat exchanger 31 to the ambient air (outside air). It is for making it happen. A return refrigerant pipe 37 is connected to the outlet side of the external heat exchanger 32.

  One end of the return refrigerant pipe 37 is connected to the outlet side of the external heat exchanger 32, and the other end is connected to the refrigerant pipe 25 constituting the main refrigerant circuit 20, and is condensed in the internal heat exchanger 31. This is a return path for returning to the main refrigerant circuit 20 the refrigerant that has been condensed, more specifically, the refrigerant that has been condensed by the internal heat exchanger 31 and radiated by the external heat exchanger 32.

  Here, the other end of the return refrigerant pipe 37 is connected to a predetermined point (merging point) 254 in the refrigerant pipe 25 between the two capillary tubes 231 and 232 constituting the main refrigerant circuit 20. That is, the return refrigerant pipe 37 supplies the refrigerant condensed in the internal heat exchanger 31 (and the external heat exchanger 32) between the adjacent capillary tubes 231 and 232 constituting the expansion mechanism 23, and is mainly supplied. It is returned to the refrigerant circuit 20.

  In the refrigerant circuit device 10 having the above-described configuration, the product stored in the product storage 3 is cooled or heated as follows.

  First, the case where the goods accommodated in the right warehouse 3a are cooled and the goods accommodated in the middle warehouse 3b and the left warehouse 3c will be described. In such a case, as a premise, an open command is given to the branch solenoid valves 341 and 342 and the low pressure side solenoid valve 263 upstream of the first evaporator 24a, and the high pressure side solenoid valve 261 and the second evaporator 24b are opened. The low pressure side solenoid valves 264 and 265 upstream of the third evaporator 24c are closed by giving a close command. Moreover, each internal ventilation fan F2-F4 and the external ventilation fan F1 are driven.

  In the sub refrigerant circuit 30 of the refrigerant circuit device 10, a part of the refrigerant compressed by the compressor 21 is branched and reaches each internal heat exchanger 31 through the branch introduction refrigerant pipe 33. The refrigerant that has reached each internal heat exchanger 31 passes through each internal heat exchanger 31, exchanges heat with the internal air of the central storage 3b and the left storage 3c, and dissipates heat to the internal air to condense. Thereby, the internal air of the inner warehouse 3b and the left warehouse 3c is heated. The heated internal air circulates inside each product storage 3 by driving the internal blower fan F3 and the left internal blower fan F4, whereby each product storage 3 (the central store 3b and the left store 3c). ) Is heated by circulating internal air. The refrigerant condensed in the internal heat exchanger 31 reaches the external heat exchanger 32 through the refrigerant pipe 35, radiates heat to the ambient air in the external heat exchanger 32, and then returns to the main refrigerant circuit 20 through the return refrigerant pipe 37. That is, it returns between the two capillary tubes 231 and 232 and thereafter expands through the capillary tube 232 on the downstream side. The refrigerant that has expanded through the capillary tube 232 reaches the first evaporator 24a, evaporates in the first evaporator 24a, takes heat from the internal air of the right case 3a, and cools the internal air. The refrigerant evaporated in the first evaporator 24a is gas-liquid separated by the accumulator 27, and then the gas phase portion is sucked into the compressor 21 and compressed by the compressor 21 to repeat the above-described circulation.

  Next, in order to cool the products stored in all the product storage boxes 3, the high pressure side solenoid valves 261 and all the low pressure side solenoid valves 263, 264, 265 are given open commands while being opened. All branch solenoid valves 341 and 342 are closed by giving a close command. Thereby, in the product storage device, the refrigerant is circulated only in the main refrigerant circuit 20.

  The refrigerant compressed by the compressor 21 reaches the condenser 22, condenses in the condenser 22, and then passes through the two capillary tubes 231 and 232 that are arranged in series to form the expansion mechanism 23. Inflate. The refrigerant that has expanded through the capillary tubes 231 and 232 reaches the first evaporator 24a to the third evaporator 24c, evaporates in each of the evaporators 24, and takes heat from the internal air of the product storage case 3, Cool the air. The cooled internal air circulates in the interior by driving the internal blower fans F <b> 2 to F <b> 4, whereby the products stored in each product storage 3 are cooled to the circulating internal air. The refrigerant evaporated in each evaporator 24 is separated into gas and liquid by the accumulator 27, and then the gas phase portion is sucked into the compressor 21 and compressed by the compressor 21 to repeat the above-described circulation.

  As described above, in the refrigerant circuit device 10, there is a heat exchanger that is not used, that is, a heat exchanger that is not in use when the product stored in the product storage 3 is cooled or heated. Since the refrigerant may stay in the heat exchanger that is not in operation, a pump-down operation is performed in which the compressor 21 is driven to suck the refrigerant in the circuit every predetermined time schedule.

  An example of such a pump-down operation will be described. An open command is given to the low pressure side solenoid valve 263 and the high pressure side solenoid valve 261 upstream of the first evaporator 24a to open them, and the remaining solenoid valves (branch solenoid valves 341, 342). The other low pressure side solenoid valves 264, 265) are closed by giving a close command. Then, the compressor 21 is driven to suck the refrigerant.

  According to the refrigerant circuit device 10 in the first embodiment, the two capillary tubes 231 and 232 are arranged in a serial manner to constitute the expansion mechanism 23, and the return refrigerant pipe 37 is connected to the internal heat exchanger 31 (and Since the refrigerant that has passed through the external heat exchanger 32) is supplied to the junction 254 between the two capillary tubes 231 and 232 and returned to the main refrigerant circuit 20, when the refrigerant in the sub refrigerant circuit 30 is sucked, It is not necessary to pass all the capillary tubes 231 and 232 constituting the expansion mechanism 23, and only one capillary tube 232 needs to be passed. Therefore, the resistance in the capillary tubes 231 and 232 can be relatively lowered. Thereby, the time required for pumping down can be shortened, and as a result, power consumption can be reduced. Further, since the capillary tubes 231 and 232 are used, the cost can be reduced as compared with the use of an electronic expansion valve or the like. Accordingly, it is possible to reduce the time required for pumping down and reduce power consumption while reducing the cost.

  Moreover, since such a pump-down operation can be performed satisfactorily, the refrigerant circulation amount can be distributed according to the load of each evaporator 24, and the operation efficiency can be improved.

  As mentioned above, although Embodiment 1 of this invention was described, this invention is not limited to this, As shown in FIG.4 and FIG.5, various changes can be made. 4 and 5 that have the same configuration as the refrigerant circuit device 10 in the first embodiment described above are denoted by the same reference numerals.

  In the first embodiment described above, the expansion mechanism 23 is configured by arranging the two capillary tubes 231 and 232 in series in a substantially continuous manner, but in the present invention, as shown in FIG. One capillary tube 232a, 232b, 232c constituting the expansion mechanism 23 is disposed between the low pressure side solenoid valves 263, 264, 265 and the evaporator 24, and upstream of the low pressure side solenoid valves 263, 264, 265. The expansion mechanism 23 may be configured together with the capillary tube 231. Even with such a configuration, it is possible to reduce the time required for pumping down and reduce power consumption while reducing costs.

  In the first embodiment described above, the middle warehouse 3b and the left warehouse 3c include an evaporator 24 (second evaporator 24b and third evaporator 24c), and an in-compartment heat exchanger 31 separate from the evaporator 24 (second evaporator 24b and third evaporator 24c). However, in the present invention, as shown in FIG. 5, the heat in which the evaporator 24 constituting the main refrigerant circuit 20 and the internal heat exchanger 31 constituting the sub refrigerant circuit 30 are integrated. The exchanger 28 may be used. In FIG. 5, reference numerals 281, 282, 381 and 382 are solenoid valves, and reference numerals 283, 284, 383 and 384 are check valves.

  Even with such a configuration, it is possible to reduce the time required for pumping down and reduce power consumption while reducing costs.

<Embodiment 2>
FIG. 6 is a conceptual diagram conceptually showing the structure of the refrigerant circuit device according to Embodiment 2 of the present invention. In addition, the same code | symbol is attached | subjected to what has the same structure as the refrigerant circuit apparatus 10 (refrigerant circuit apparatus illustrated in FIG. 3) which is Embodiment 1 mentioned above, and the description is abbreviate | omitted suitably. The refrigerant circuit device 11 exemplified here includes a main refrigerant circuit 20 and a sub refrigerant circuit 30a.

  The main refrigerant circuit 20 is configured by sequentially connecting a compressor 21, a condenser 22, an expansion mechanism 23, and an evaporator 24 through a refrigerant pipe 25, and a refrigerant is enclosed therein.

  The compressor 21 sucks the refrigerant through the suction port, compresses the sucked refrigerant to be in a high-temperature and high-pressure state (high-temperature and high-pressure refrigerant), and discharges it from the discharge port.

  The condenser 22 condenses the refrigerant that passes therethrough. More specifically, the refrigerant compressed by the compressor 21 and discharged from the discharge port and sent out through the refrigerant pipe 25 is condensed by exchanging heat with ambient air.

  The refrigerant pipe 25 connecting the condenser 22 and the compressor 21 is provided with a high-pressure side electromagnetic valve 261. The high-pressure side electromagnetic valve 261 is a valve body that can be opened and closed. When the open command is given, the high-pressure side solenoid valve 261 opens and allows the refrigerant to pass therethrough. It regulates the passage of

  The expansion mechanism 23 is configured by arranging a plurality (two in the illustrated example) of capillary tubes 231 and 232 in a serial manner, and adiabatically expands the refrigerant passing through by reducing the pressure.

  A plurality (three in the illustrated example) of the evaporators 24 are provided, and are disposed inside each commodity storage 3. Here, the refrigerant pipe 25 that connects the evaporator 24 and the expansion mechanism 23 (capillary tube 232) branches into three at a branch point 251 in the middle, and the first evaporation disposed in the right warehouse 3a. It is connected to the inlet side of the second evaporator 24b arranged in the inner warehouse 3b, to the inlet side of the third evaporator 24c arranged inside the left warehouse 3c, on the inlet side of the container 24a.

  In the refrigerant pipe 25, low-pressure side solenoid valves 263, 264, and 265 are provided on the way from the branch point 251 to each of the first evaporator 24a to the third evaporator 24c. The low-pressure side solenoid valves 263, 264, and 265 are openable and closable valve elements that open when a command to open is given and allow the refrigerant to pass, but close when a command to close is given. Thus, the passage of the refrigerant is restricted. The refrigerant pipes 25 connected to the outlet side of these evaporators 24 are merged at a midway junction 252 and connected to the compressor 21 via the accumulator 27.

  The sub refrigerant circuit 30a is a circuit formed by branching from the main refrigerant circuit 20, and includes an internal heat exchanger 31, an external heat exchanger 32, a bypass pipe (bypass path) 40, and a bypass valve 41. Yes.

  A plurality (two in the illustrated example) of the internal heat exchangers 31 are provided, one of which is disposed inside the middle warehouse 3b and the other is disposed inside the left warehouse 3c. These internal heat exchangers 31 exchange heat with the internal air (internal atmosphere) of the product storage 3 (the central storage 3b and the left storage 3c) in which the passing refrigerant is disposed, that is, the refrigerant and the target that pass therethrough. This is to exchange heat with the internal air of the product storage 3. These internal heat exchangers 31 are connected to the compressor 21 via a common branch introduction refrigerant pipe 33.

  The branch introduction refrigerant pipe 33 introduces a refrigerant (high pressure refrigerant) branched from the high pressure side branch point 253 in the middle of the refrigerant pipe 25 connecting the compressor 21 and the condenser 22 and compressed by the compressor 21. It is. The branch introduction refrigerant pipe 33 is further branched in the middle, and one side is connected to the internal heat exchanger 31 of the internal storage 3b and the other is connected to the internal heat exchanger 31 of the left storage 3c.

  In the branch introduction refrigerant pipe 33, branch solenoid valves 341 and 342 are provided on the downstream side of the branch point, respectively. The branch solenoid valves 341 and 342 are valve bodies that can be opened and closed. When the opening command is given, the branching electromagnetic valves 341 and 342 are opened to allow the refrigerant to pass therethrough. It regulates the passage of

  In other words, each of the internal heat exchangers 31 is supplied with the refrigerant compressed by the compressor 21 through the branch introduction refrigerant pipe 33, and therefore condenses the refrigerant that passes therethrough to be the target product storage 3 (inside The internal air of the storage 3b and the left storage 3c) is heated.

  Here, an internal blower fan is disposed inside each commodity storage 3. The blower fan F2 in the right warehouse inside the right warehouse 3a is disposed in the vicinity of the first evaporator 24a, and circulates the internal air cooled by the first evaporator 24a inside the right warehouse 3a. It is. The internal blower fan F3 in the internal storage 3b is disposed in the vicinity of the second evaporator 24b and the internal heat exchanger 31, and the internal air cooled by the second evaporator 24b, or the internal The internal air heated by the internal heat exchanger 31 is circulated inside the storage 3b. The left internal blower fan F4 inside the left storage 3c is disposed in the vicinity of the third evaporator 24c and the internal heat exchanger 31, and the internal air cooled by the third evaporator 24c, or the storage The internal air heated by the internal heat exchanger 31 is circulated inside the left warehouse 3c.

  Refrigerant pipes 35 are respectively connected to the outlet sides of these internal heat exchangers 31, and these refrigerant pipes 35 are joined on the way and connected to the inlet side of the external heat exchanger 32.

  The external heat exchanger 32 exchanges heat between the passing refrigerant and ambient air, that is, heat exchange between passing air and ambient air (for example, outside air). More specifically, the external heat exchanger 32 radiates the refrigerant supplied from the internal heat exchanger 31 through the refrigerant pipe 35, that is, the refrigerant condensed in the internal heat exchanger 31 to the ambient air (outside air). It is for making it happen. A return refrigerant pipe 37 is connected to the outlet side of the external heat exchanger 32.

  One end of the return refrigerant pipe 37 is connected to the outlet side of the external heat exchanger 32, and the other end is connected to the refrigerant pipe 25 constituting the main refrigerant circuit 20, and is condensed in the internal heat exchanger 31. This is a return path for returning to the main refrigerant circuit 20 the refrigerant that has been condensed, more specifically, the refrigerant that has been condensed by the internal heat exchanger 31 and radiated by the external heat exchanger 32.

  Here, the other end of the return refrigerant pipe 37 is connected to a junction 254 in the refrigerant pipe 25 between the two capillary tubes 231 and 232 constituting the main refrigerant circuit 20. That is, the return refrigerant pipe 37 supplies the refrigerant condensed in the internal heat exchanger 31 between the adjacent capillary tubes 231 and 232 constituting the expansion mechanism 23 and returns the refrigerant to the main refrigerant circuit 20.

  The bypass pipe 40 is branched in the middle of the return refrigerant pipe 37, that is, downstream of the external heat exchanger 32 and in the middle of the upstream of the junction point 254, and the low pressure side solenoid valve 263 and the first evaporator. It is provided in such a manner that it merges with the refrigerant pipe 25 between 24a and 24a. This bypass pipe 40 branches in the middle of the path from the internal heat exchanger 31 to the merge point 254, and is arranged in a manner to merge in the middle of the path from the expansion mechanism 23 to the evaporator 24, and introduced refrigerant Is sent to the main refrigerant circuit 20.

  The bypass valve 41 is provided in the bypass pipe 40. The bypass valve 41 is a valve body that can be opened and closed. When the opening command is given, the bypass valve 41 opens and allows the refrigerant to pass through the bypass pipe 40, while when the closing command is given, the bypass valve 41 closes. Thus, the refrigerant is restricted from passing through the bypass pipe 40.

  In the refrigerant circuit device 11 having the above configuration, the product stored in the product storage 3 is cooled or heated as follows.

  First, the case where the goods accommodated in the right warehouse 3a are cooled and the goods accommodated in the middle warehouse 3b and the left warehouse 3c will be described. In such a case, as a premise, an open command is given to the branch solenoid valves 341 and 342 and the low pressure side solenoid valve 263 upstream of the first evaporator 24a, and the high pressure side solenoid valve 261 and the second evaporator 24b are opened. And the low pressure side solenoid valves 264 and 265 upstream of the third evaporator 24c and the bypass valve 41 are closed by giving a close command. Moreover, each internal ventilation fan F2-F4 and the external ventilation fan F1 are driven.

  In the sub refrigerant circuit 30 a of the refrigerant circuit device 11, a part of the refrigerant compressed by the compressor 21 is branched and reaches each internal heat exchanger 31 through the branch introduction refrigerant pipe 33. The refrigerant that has reached each internal heat exchanger 31 passes through each internal heat exchanger 31, exchanges heat with the internal air of the central storage 3b and the left storage 3c, and dissipates heat to the internal air to condense. Thereby, the internal air of the inner warehouse 3b and the left warehouse 3c is heated. The heated internal air circulates inside each product storage 3 by driving the internal blower fan F3 and the left internal blower fan F4, whereby each product storage 3 (the central store 3b and the left store 3c). ) Is heated by circulating internal air. The refrigerant condensed in the internal heat exchanger 31 reaches the external heat exchanger 32 through the refrigerant pipe 35, radiates heat in the external heat exchanger 32, and then returns to the main refrigerant circuit 20, that is, the two refrigerants through the return refrigerant pipe 37. It returns between the capillary tubes 231 and 232, and then expands through the capillary tube 232 on the downstream side. The refrigerant that has expanded through the capillary tube 232 reaches the first evaporator 24a, evaporates in the first evaporator 24a, takes heat from the internal air of the right case 3a, and cools the internal air. The refrigerant evaporated in the first evaporator 24a is gas-liquid separated by the accumulator 27, and then the gas phase portion is sucked into the compressor 21 and compressed by the compressor 21 to repeat the above-described circulation.

  Next, in order to cool the products stored in all the product storage boxes 3, the high pressure side solenoid valves 261 and all the low pressure side solenoid valves 263, 264, 265 are given open commands while being opened. All branch solenoid valves 341 and 342 and the bypass valve 41 are closed by giving a close command. Thereby, in the product storage device, the refrigerant is circulated only in the main refrigerant circuit 20.

  The refrigerant compressed by the compressor 21 reaches the condenser 22, condenses in the condenser 22, and then expands through the two capillary tubes 231 and 232 arranged in series constituting the expansion mechanism 23. The refrigerant that has expanded through the capillary tubes 231 and 232 reaches the first evaporator 24a to the third evaporator 24c, evaporates in each of the evaporators 24, and takes heat from the internal air of the product storage case 3, Cool the air. The cooled internal air circulates in the interior by driving the internal blower fans F <b> 2 to F <b> 4, whereby the products stored in each product storage 3 are cooled to the circulating internal air. The refrigerant evaporated in each evaporator 24 is separated into gas and liquid by the accumulator 27, and then the gas phase portion is sucked into the compressor 21 and compressed by the compressor 21 to repeat the above-described circulation.

  As described above, in the refrigerant circuit device 11, there is a heat exchanger that is not used, that is, a heat exchanger that is not in use when the product stored in the product storage 3 is cooled or heated. Since the refrigerant may stay in the heat exchanger that is not in operation, a pump-down operation is performed in which the compressor 21 is driven to suck the refrigerant in the circuit every predetermined time schedule.

  An example of such a pump-down operation will be described. An open command is given to the low pressure side solenoid valve 263, the high pressure side solenoid valve 261, and the bypass valve 41 upstream of the first evaporator 24a to open the remaining solenoid valves (branch). The solenoid valves 341 and 342 and the other low pressure side solenoid valves 264 and 265) are closed by giving a close command. Then, the refrigerant may be sucked by driving the compressor 21.

  Thus, the refrigerant staying in the internal heat exchanger 31 and the external heat exchanger 32 enters the bypass pipe 40, passes through the bypass pipe 40, passes through the first evaporator 24 a, and passes through the accumulator 27. It is sucked into the compressor 21.

  As described above, according to the refrigerant circuit device 11 in Embodiment 2 of the present invention, when performing the pump-down operation, the internal heat exchanger 31 and the external heat exchanger are opened by opening the bypass valve 41. The refrigerant staying at 32 can be introduced into the bypass pipe 40, and after passing through the bypass pipe 40, can be sucked into the compressor 21 via the first evaporator 24 a and the accumulator 27. That is, during the pump-down operation, the compressor 21 can be sucked without passing through the capillary tubes 231 and 232 constituting the expansion mechanism 23. Thereby, the time required for pumping down can be shortened, and as a result, power consumption can be reduced. Further, since the capillary tubes 231 and 232 are used, the cost can be reduced as compared with the use of an electronic expansion valve or the like. Accordingly, it is possible to reduce the time required for pumping down and reduce power consumption while reducing the cost.

  Moreover, since such a pump-down operation can be performed satisfactorily, the refrigerant circulation amount can be distributed according to the load of each evaporator 24, and the operation efficiency can be improved.

  As mentioned above, although Embodiment 2 of this invention was described, this invention is not limited to this, A various change can be made as shown in FIG. In addition, in FIG. 7, the same code | symbol is attached | subjected to what has the same structure as the refrigerant circuit apparatus 11 in Embodiment 2 mentioned above.

  In the second embodiment described above, the bypass pipe 40 is downstream of the external heat exchanger 32 and is branched in the middle of the upstream of the junction 254, and the low-pressure side electromagnetic valve 263 and the first evaporator 24a. However, in the present invention, as shown in FIG. 7, the downstream side of the external heat exchanger 32 and the upstream side of the junction point 254 are provided. And may be provided in such a manner that it merges with the refrigerant pipe 25 between the expansion mechanism 23 and the branch point 251. Even with such a configuration, it is possible to reduce the time required for pumping down and reduce power consumption while reducing costs.

<Embodiment 3>
FIG. 8 is a conceptual diagram conceptually showing the structure of the refrigerant circuit device according to Embodiment 3 of the present invention. In addition, the same code | symbol is attached | subjected to what has the same structure as the refrigerant circuit apparatus 10 (refrigerant circuit apparatus illustrated in FIG. 3) which is Embodiment 1 mentioned above, and the description is abbreviate | omitted suitably. The refrigerant circuit device 12 exemplified here includes a main refrigerant circuit 20a and a sub refrigerant circuit 30a.

  The main refrigerant circuit 20a is configured by sequentially connecting a compressor 21, a condenser 22, an expansion mechanism 23, and an evaporator 24 through a refrigerant pipe 25, and includes a first bypass pipe (another bypass path) 42 and a first One bypass valve (another bypass valve) 43 is provided.

  The compressor 21 sucks the refrigerant through the suction port, compresses the sucked refrigerant to be in a high-temperature and high-pressure state (high-temperature and high-pressure refrigerant), and discharges it from the discharge port.

  The condenser 22 condenses the refrigerant that passes therethrough. More specifically, the refrigerant compressed by the compressor 21 and discharged from the discharge port and sent out through the refrigerant pipe 25 is condensed by exchanging heat with ambient air.

  The refrigerant pipe 25 connecting the condenser 22 and the compressor 21 is provided with a high-pressure side electromagnetic valve 261. The high-pressure side electromagnetic valve 261 is a valve body that can be opened and closed. When the open command is given, the high-pressure side solenoid valve 261 opens and allows the refrigerant to pass therethrough. It regulates the passage of

  The expansion mechanism 23 is configured by arranging a plurality (two in the illustrated example) of capillary tubes 231 and 232 in a serial manner, and adiabatically expands the refrigerant passing through by reducing the pressure.

  A plurality (three in the illustrated example) of the evaporators 24 are provided, and are disposed inside each commodity storage 3. Here, the refrigerant pipe 25 that connects the evaporator 24 and the expansion mechanism 23 (capillary tube 232) branches into three at a branch point 251 in the middle, and the first evaporation disposed in the right warehouse 3a. It is connected to the inlet side of the second evaporator 24b arranged in the inner warehouse 3b, to the inlet side of the third evaporator 24c arranged inside the left warehouse 3c, on the inlet side of the container 24a.

  In the refrigerant pipe 25, low-pressure side solenoid valves 263, 264, and 265 are provided on the way from the branch point 251 to each of the first evaporator 24a to the third evaporator 24c. The low-pressure side solenoid valves 263, 264, and 265 are openable and closable valve elements that open when a command to open is given and allow the refrigerant to pass, but close when a command to close is given. Thus, the passage of the refrigerant is restricted. The refrigerant pipes 25 connected to the outlet side of these evaporators 24 are merged at a midway junction 252 and connected to the compressor 21 via the accumulator 27.

  The first bypass pipe 42 branches in the middle of the refrigerant pipe 25 extending from the condenser 22 to the expansion mechanism 23 (capillary tube 231), and merges with the refrigerant pipe 25 extending from the low pressure side electromagnetic valve 263 to the first evaporator 24a. It is provided in the form. The first bypass pipe 42 is arranged in a manner that branches in the middle of the path from the condenser 22 to the expansion mechanism 23 and merges in the middle of the path from the expansion mechanism 23 to the evaporator 24. The condensed refrigerant is introduced and sent to the evaporator 24.

  The first bypass valve 43 is provided in the first bypass pipe 42. The first bypass valve 43 is a valve body that can be opened and closed. When the opening command is given, the first bypass valve 43 opens and allows the refrigerant to pass through the first bypass pipe 42 while being given a closing command. In this case, the refrigerant is closed to restrict the refrigerant from passing through the first bypass pipe 42.

  The sub refrigerant circuit 30a is a circuit formed by branching from the main refrigerant circuit 20a, and the internal heat exchanger 31, the external heat exchanger 32, the second bypass pipe (bypass path) 44, and the second bypass valve. (Bypass valve) 45 is provided.

  A plurality (two in the illustrated example) of the internal heat exchangers 31 are provided, one of which is disposed inside the middle warehouse 3b and the other is disposed inside the left warehouse 3c. These internal heat exchangers 31 exchange heat with the internal air (internal atmosphere) of the product storage 3 (the central storage 3b and the left storage 3c) in which the passing refrigerant is disposed, that is, the refrigerant and the target that pass therethrough. This is to exchange heat with the internal air of the product storage 3. These internal heat exchangers 31 are connected to the compressor 21 via a common branch introduction refrigerant pipe 33.

  The branch introduction refrigerant pipe 33 introduces a refrigerant (high pressure refrigerant) branched from the high pressure side branch point 253 in the middle of the refrigerant pipe 25 connecting the compressor 21 and the condenser 22 and compressed by the compressor 21. It is. The branch introduction refrigerant pipe 33 is further branched in the middle, and one side is connected to the internal heat exchanger 31 of the internal storage 3b and the other is connected to the internal heat exchanger 31 of the left storage 3c.

  In the branch introduction refrigerant pipe 33, branch solenoid valves 341 and 342 are provided on the downstream side of the branch point, respectively. The branch solenoid valves 341 and 342 are valve bodies that can be opened and closed. When the opening command is given, the branching electromagnetic valves 341 and 342 are opened to allow the refrigerant to pass therethrough. It regulates the passage of

  In other words, each of the internal heat exchangers 31 is supplied with the refrigerant compressed by the compressor 21 through the branch introduction refrigerant pipe 33, and therefore condenses the refrigerant that passes therethrough to be the target product storage 3 (inside The internal air of the storage 3b and the left storage 3c) is heated.

  Here, an internal blower fan is disposed inside each commodity storage 3. The blower fan F2 in the right warehouse inside the right warehouse 3a is disposed in the vicinity of the first evaporator 24a, and circulates the internal air cooled by the first evaporator 24a inside the right warehouse 3a. It is. The internal blower fan F3 in the internal storage 3b is disposed in the vicinity of the second evaporator 24b and the internal heat exchanger 31, and the internal air cooled by the second evaporator 24b, or the internal The internal air heated by the internal heat exchanger 31 is circulated inside the storage 3b. The left internal blower fan F4 inside the left storage 3c is disposed in the vicinity of the third evaporator 24c and the internal heat exchanger 31, and the internal air cooled by the third evaporator 24c, or the storage The internal air heated by the internal heat exchanger 31 is circulated inside the left warehouse 3c.

  Refrigerant pipes 35 are respectively connected to the outlet sides of these internal heat exchangers 31, and these refrigerant pipes 35 are joined on the way and connected to the inlet side of the external heat exchanger 32.

  The external heat exchanger 32 is disposed in the machine room 9 similarly to the compressor 21. The external heat exchanger 32 exchanges heat between the passing refrigerant and ambient air, that is, heat exchange between passing air and ambient air (for example, outside air). More specifically, the external heat exchanger 32 radiates the refrigerant supplied from the internal heat exchanger 31 through the refrigerant pipe 35, that is, the refrigerant condensed in the internal heat exchanger 31 to the ambient air (outside air). It is for making it happen. A return refrigerant pipe 37 is connected to the outlet side of the external heat exchanger 32.

  One end of the return refrigerant pipe 37 is connected to the outlet side of the external heat exchanger 32, and the other end is connected to the refrigerant pipe 25 constituting the main refrigerant circuit 20 a, and is condensed by the internal heat exchanger 31. This is a return path for returning the condensed refrigerant, more specifically, the refrigerant condensed in the internal heat exchanger 31 and radiated by the external heat exchanger 32 to the main refrigerant circuit 20a.

  Here, the other end of the return refrigerant pipe 37 is connected to a junction 254 in the refrigerant pipe 25 between the two capillary tubes 231 and 232 constituting the main refrigerant circuit 20a. That is, the return refrigerant pipe 37 supplies the refrigerant condensed in the internal heat exchanger 31 between the adjacent capillary tubes 231 and 232 constituting the expansion mechanism 23 and returns the refrigerant to the main refrigerant circuit 20a.

  The second bypass pipe 44 branches in the middle of the return refrigerant pipe 37, that is, downstream of the external heat exchanger 32 and in the middle of the upstream of the junction 254, and the expansion mechanism 23 (capillary tube 232). Are provided in such a manner that they merge into the refrigerant pipe 25 between the branch point 251 and the branch point 251. This second bypass pipe 44 is arranged in such a manner that it is branched in the middle of the path from the internal heat exchanger 31 to the merge point 254 and merges in the middle of the path from the expansion mechanism 23 to the evaporator 24. The discharged refrigerant is sent to the main refrigerant circuit 20a.

  The second bypass valve 45 is provided in the second bypass pipe 44. The second bypass valve 45 is a valve body that can be opened and closed. When the opening command is given, the second bypass valve 45 opens and allows the refrigerant to pass through the second bypass pipe 44, while the closing command is given. In this case, the refrigerant is closed to restrict the refrigerant from passing through the second bypass pipe 44.

  In the refrigerant circuit device 12 having the above-described configuration, the product stored in the product storage 3 is cooled or heated as follows.

  First, the case where the goods accommodated in the right warehouse 3a are cooled and the goods accommodated in the middle warehouse 3b and the left warehouse 3c will be described. In such a case, as a premise, an open command is given to the branch solenoid valves 341 and 342 and the low pressure side solenoid valve 263 upstream of the first evaporator 24a, and the high pressure side solenoid valve 261 and the second evaporator 24b are opened. The low pressure side solenoid valves 264, 265, the first bypass valve 43, and the second bypass valve 45 upstream of the third evaporator 24c are closed by closing them. Moreover, each internal ventilation fan F2-F4 and the external ventilation fan F1 are driven.

  In the sub refrigerant circuit 30 a of the refrigerant circuit device 12, a part of the refrigerant compressed by the compressor 21 is branched and reaches each internal heat exchanger 31 through the branch introduction refrigerant pipe 33. The refrigerant that has reached each internal heat exchanger 31 passes through each internal heat exchanger 31, exchanges heat with the internal air of the central storage 3b and the left storage 3c, and dissipates heat to the internal air to condense. Thereby, the internal air of the inner warehouse 3b and the left warehouse 3c is heated. The heated internal air circulates inside each product storage 3 by driving the internal blower fan F3 and the left internal blower fan F4, whereby each product storage 3 (the central store 3b and the left store 3c). ) Is heated by circulating internal air. The refrigerant condensed in the internal heat exchanger 31 reaches the external heat exchanger 32 through the refrigerant pipe 35, radiates heat in the external heat exchanger 32, and then passes through the return refrigerant pipe 37 to the main refrigerant circuit 20a, that is, the two refrigerants. It returns between the capillary tubes 231 and 232, and then expands through the capillary tube 232 on the downstream side. The refrigerant that has expanded through the capillary tube 232 reaches the first evaporator 24a, evaporates in the first evaporator 24a, takes heat from the internal air of the right case 3a, and cools the internal air. The refrigerant evaporated in the first evaporator 24a is gas-liquid separated by the accumulator 27, and then the gas phase portion is sucked into the compressor 21 and compressed by the compressor 21 to repeat the above-described circulation.

  Next, in order to cool the products stored in all the product storage boxes 3, the high pressure side solenoid valves 261 and all the low pressure side solenoid valves 263, 264, 265 are given open commands while being opened. All the branch solenoid valves 341, 342, the first bypass valve 43, and the second bypass valve 45 are closed by giving a close command. Thereby, in the product storage device, the refrigerant is circulated only in the main refrigerant circuit 20a.

  The refrigerant compressed by the compressor 21 reaches the condenser 22, condenses in the condenser 22, and then expands through the two capillary tubes 231 and 232 arranged in series constituting the expansion mechanism 23. The refrigerant that has expanded through the capillary tubes 231 and 232 reaches the first evaporator 24a to the third evaporator 24c, evaporates in each of the evaporators 24, and takes heat from the internal air of the product storage case 3, Cool the air. The cooled internal air circulates in the interior by driving the internal blower fans F <b> 2 to F <b> 4, whereby the products stored in each product storage 3 are cooled to the circulating internal air. The refrigerant evaporated in each evaporator 24 is separated into gas and liquid by the accumulator 27, and then the gas phase portion is sucked into the compressor 21 and compressed by the compressor 21 to repeat the above-described circulation.

  As described above, in the refrigerant circuit device 12, there is a heat exchanger that is not used, that is, a heat exchanger that is not in use when the product stored in the product storage 3 is cooled or heated. Since the refrigerant may stay in the heat exchanger that is not in operation, a pump-down operation is performed in which the compressor 21 is driven to suck the refrigerant in the circuit every predetermined time schedule.

  An example of such a pump-down operation will be described. An open command is given to the low pressure side solenoid valve 263, the first bypass valve 43, and the second bypass valve 45 upstream of the first evaporator 24a, and the remaining solenoid valves are opened. A close command is given to the high pressure side solenoid valve 261, the branch solenoid valves 341 and 342, and the other low pressure side solenoid valves 264 and 265 to close them. Then, the refrigerant may be sucked by driving the compressor 21.

  Thereby, the refrigerant staying in the condenser 22 enters the first bypass pipe 42, and the refrigerant staying in the internal heat exchanger 31 and the external heat exchanger 32 enters the second bypass pipe 44. The refrigerant that has entered and passed through the first bypass pipe 42 and the refrigerant that has entered and passed through the second bypass pipe 44 then pass through the first evaporator 24 a and are sucked into the compressor 21 through the accumulator 27. .

  As described above, according to the refrigerant circuit device 12 in the third embodiment of the present invention, when performing the pump-down operation, the condenser 22 is opened by opening the first bypass valve 43 and the second bypass valve 45. Refrigerant that has accumulated in the first bypass pipe 42 and that has accumulated in the internal heat exchanger 31 or the external heat exchanger 32 has been introduced into the second bypass pipe 44 and has passed through the first bypass pipe 42. The refrigerant that has passed through the second bypass pipe 44 can be sucked into the compressor 21 via the first evaporator 24 a and the accumulator 27. That is, during the pump-down operation, the compressor 21 can be sucked without passing through the capillary tubes 231 and 232 constituting the expansion mechanism 23. Thereby, the time required for pumping down can be shortened, and as a result, power consumption can be reduced. Further, since the capillary tubes 231 and 232 are used, the cost can be reduced as compared with the use of an electronic expansion valve or the like. Accordingly, it is possible to reduce the time required for pumping down and reduce power consumption while reducing the cost.

  Moreover, since such a pump-down operation can be performed satisfactorily, the refrigerant circulation amount can be distributed according to the load of each evaporator 24, and the operation efficiency can be improved.

  As mentioned above, although Embodiment 3 of this invention was described, this invention is not limited to this, A various change can be performed.

  In the above-described third embodiment, the second bypass pipe 44 and the second bypass valve 45 are provided. However, in the present invention, the second bypass pipe 44 and the second bypass valve 45 are not essential components. It does not matter if it is not provided.

It is sectional drawing which shows the case where the internal structure of the vending machine to which the refrigerant circuit apparatus which is Embodiment 1 of this invention is applied is seen from the front. FIG. 2 is a cross-sectional side view of the right product storage case, showing the internal structure of the vending machine shown in FIG. 1. It is a conceptual diagram which shows notionally the refrigerant circuit apparatus applied to the vending machine shown in FIG. 1 and FIG. It is a conceptual diagram which shows notionally the modification of the refrigerant circuit apparatus which is Embodiment 1 of this invention. It is a conceptual diagram which shows notionally the modification of the refrigerant circuit apparatus which is Embodiment 1 of this invention. It is a conceptual diagram which shows notionally the structure of the refrigerant circuit apparatus in Embodiment 2 of this invention. It is a conceptual diagram which shows notionally the modification of the refrigerant circuit apparatus which is Embodiment 2 of this invention. It is a conceptual diagram which shows notionally the structure of the refrigerant circuit apparatus in Embodiment 3 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Main body cabinet 10, 11, 12 Refrigerant circuit apparatus 20, 20a Main refrigerant circuit 21 Compressor 22 Condenser 23 Expansion mechanism 231,232 Capillary tube 24 Evaporator 25 Refrigerant piping 30, 30a Sub-refrigerant circuit 31 Heat exchanger 32 in a store | warehouse | chamber External heat exchanger 33 Branch introduction refrigerant pipe 37 Return refrigerant pipe 40 Bypass pipe 41 Bypass valve 42 First bypass pipe 43 First bypass valve 44 Second bypass pipe 45 Second bypass valve

Claims (4)

An evaporator disposed inside a chamber to be cooled and evaporating the supplied refrigerant to cool the internal atmosphere of the chamber;
A compressor that sucks and compresses the refrigerant evaporated in the evaporator;
A condenser for introducing and condensing the refrigerant compressed by the compressor;
A main refrigerant circuit configured by sequentially connecting refrigerant expansion pipes and an expansion mechanism for supplying the refrigerant condensed by the condenser and supplying the refrigerant to the evaporator;
A branch introduction path for branching and introducing the refrigerant compressed by the compressor;
An indoor heat exchanger that is disposed inside a chamber to be heated, condenses the refrigerant introduced through the branch introduction path, and heats the internal atmosphere of the chamber;
A refrigerant circuit device comprising: a sub-refrigerant circuit having a return path for returning the refrigerant that has passed through the indoor heat exchanger to the main refrigerant circuit;
The expansion mechanism is configured by arranging a plurality of capillary tubes in a serial manner.
The refrigerant circuit device characterized in that the return path supplies the refrigerant to a junction between adjacent capillary tubes constituting the expansion mechanism and returns the refrigerant to the main refrigerant circuit. The sub refrigerant circuit includes an outdoor heat exchanger that is disposed outside the chamber to be heated, introduces the refrigerant condensed in the indoor heat exchanger, and dissipates heat to ambient air.
The refrigerant circuit device according to claim 1, wherein the return path supplies the refrigerant that has passed through the outdoor heat exchanger to the junction, and returns the refrigerant to the main refrigerant circuit. The refrigerant is branched in the middle of the path from the indoor heat exchanger to the junction, and joined in the middle of the path from the expansion mechanism to the evaporator, and the introduced refrigerant is sent to the main refrigerant circuit. Bypass path to
The refrigerant circuit according to claim 1, further comprising: a bypass valve disposed in the bypass path and allowing or restricting the refrigerant to pass through the bypass path by opening and closing. apparatus. The refrigerant branches in the middle of the path from the condenser to the expansion mechanism and joins in the middle of the path from the expansion mechanism to the evaporator, and introduces the refrigerant condensed in the condenser. Another bypass path for delivery to the evaporator;
And a bypass valve that is disposed in the other bypass path and allows or restricts the refrigerant from passing through the other bypass path by opening and closing. The refrigerant circuit device according to any one of the above.

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