JP2012002431A - Refrigerant circuit device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refrigerant circuit device capable of executing single heating operation satisfactorily by preventing an excessive increase in pressure even if the amount of a refrigerant in the refrigerant circuit is equal to an amount necessary for cooling/heating operation.SOLUTION: The refrigerant circuit device includes an in-case heat exchanger 24, a compressor 21, a main path 20 having an out-of-case heat exchanger 22, a high-pressure refrigerant introduction path 30 for supplying a refrigerant compressed by the compressor 21 to a prescribed in-case heat exchanger 24, return paths 40 and 50 for returning the refrigerant from the in-case heat exchanger 24 to the main path 20, a return valve 44 disposed in the midway of a pipe from the in-case heat exchanger 24 to a heating side heat exchanger 42, a branch path 45 for introducing the refrigerant condensed by the in-case heat exchanger 24 to expand it, and supplying the refrigerant to the heating side heat exchanger 42 when the return valve 44 is closed, and a controller 80 for closing the return valve 44 when the single heating operation is executed, and supplying the refrigerant passed through the heating side heat exchanger 42 into the in-case heat exchanger 24b disposed outside a chamber to be heated.

Description

  The present invention relates to a refrigerant circuit device, and more particularly, to a refrigerant circuit device including a refrigerant circuit having a heat pump function.

  Conventionally, the following is known as a refrigerant circuit device including a refrigerant circuit having a heat pump function. That is, a refrigerant circuit having a main path, a high-pressure refrigerant introduction path, a heat radiation path, and a return path is provided.

  The main path is configured in an annular shape by sequentially connecting the internal heat exchanger, the compressor, the external heat exchanger, and the expansion mechanism through the refrigerant pipe. The internal heat exchanger is disposed inside a target room. The compressor sucks the refrigerant that has passed through the internal heat exchanger, compresses the sucked refrigerant, and discharges it in a high-temperature and high-pressure state. The external heat exchanger introduces and condenses the refrigerant compressed by the compressor. The expansion mechanism depressurizes the refrigerant condensed in the external heat exchanger and adiabatically expands it.

  In such a main path, the refrigerant compressed by the compressor is condensed by the external heat exchanger, and the condensed refrigerant is adiabatically expanded by the expansion mechanism and evaporated by the internal heat exchanger. The refrigerant evaporated in the internal heat exchanger is sucked by the compressor, compressed again, and circulated. Thereby, the internal air of the chamber in which the internal heat exchanger is disposed is cooled.

  The high-pressure refrigerant introduction path introduces the refrigerant compressed by the compressor, and supplies it to the one disposed in the chamber to be heated among the internal heat exchangers constituting the main path. In this way, the refrigerant is condensed. Thereby, the internal air of the chamber in which the internal heat exchanger is disposed is heated.

  The heat radiation path introduces the refrigerant condensed in the internal heat exchanger and supplies it to the external heat exchanger. As a result, in the external heat exchanger, the passing refrigerant exchanges heat with ambient air and evaporates.

  The return path is a mode in which the refrigerant evaporated in the external heat exchanger is introduced and returned to the main path in a mode of being sent to the compressor. As a result, the refrigerant that has passed through the return path reaches the main path and is then sent to the compressor.

  In the refrigerant circuit device having such a configuration, when only cooling the internal air of a corresponding chamber (when performing a single cooling operation), the refrigerant may be circulated only in the main path. On the other hand, when cooling the internal air of one chamber and heating the internal air of the other chamber (when performing cooling heating operation), a part of the refrigerant compressed by the compressor is circulated in the main path, In addition, another part of the refrigerant may be circulated in the order of the high-pressure refrigerant introduction path, the heat radiation path, and the return path. Furthermore, when only heating the internal air of the corresponding chamber (when performing heating only operation), the refrigerant compressed by the compressor is passed through the high-pressure refrigerant introduction path, the heat radiation path, and the return path in this order. It may be circulated so as to return to (for example, see Patent Document 1).

JP 2000-304397 A

  By the way, in the case where the cooling heating operation is performed and the case where the heating single operation is performed, the amount of necessary refrigerant differs because the volume of the pipe through which the refrigerant flows in the refrigerant circuit is different. More specifically, the required amount of refrigerant is larger in the case of performing the cooling and heating operation than in the case of performing the single heating operation.

  Therefore, in the refrigerant circuit device proposed in Patent Document 1 described above, if the amount of refrigerant in the refrigerant circuit is made equal to the required amount during the cooling and heating operation, the amount of refrigerant becomes excessive during the single heating operation, so the pressure is excessive. As a result, the compressor may not continue to be driven and the equipment may be damaged.

  In view of the above-described circumstances, the present invention can prevent the pressure from excessively rising and perform the heating single operation satisfactorily even if the refrigerant amount in the refrigerant circuit corresponds to the necessary amount for the cooling heating operation. An object is to provide a circuit device.

  In order to achieve the above-mentioned object, a refrigerant circuit device according to claim 1 of the present invention sucks the refrigerant that has passed through the internal heat exchanger disposed inside the target chamber and the internal heat exchanger. The main path configured by sequentially connecting the compressor that compresses the refrigerant and the external heat exchanger that condenses the refrigerant compressed by the compressor with refrigerant piping, and the introduction valve provided in itself opens, High-pressure refrigerant introduction that condenses the refrigerant in the internal heat exchanger by introducing the refrigerant compressed by the compressor and supplying it to the internal heat exchanger disposed in the chamber to be heated A path, a return path for returning the refrigerant condensed in the internal heat exchanger to the upstream side of the internal heat exchanger in the main path through the heating side heat exchanger, and at least one of the main path and the return path The refrigerant provided and condensed in the external heat exchanger and the heating side A refrigerant circuit device including an expansion mechanism that adiabatically expands any of the refrigerant that has passed through the exchanger, and is disposed in the middle of the pipe from the internal heat exchanger to the heating side heat exchanger, and opens itself In the case of allowing the refrigerant to flow from the internal heat exchanger to the heating side heat exchanger, in the case where the refrigerant is closed, the refrigerant is transferred from the internal heat exchanger to the heating side heat exchanger. A return valve that restricts the flow of air, and a branch path that introduces the refrigerant condensed in the internal heat exchanger, adiabatically expands and supplies the refrigerant to the heating side heat exchanger when the return valve is closed In the case of performing heating only operation, the control for closing the return valve and causing the refrigerant that has passed through the heating side heat exchanger to flow into the in-compartment heat exchanger disposed outside the chamber to be heated Means.

  Further, the refrigerant circuit device according to claim 2 of the present invention is the above-described refrigerant circuit device according to claim 1, in which the control means allows the refrigerant that has passed through the heating-side heat exchanger to flow in when performing a single heating operation. The drive of the internal fan arranged in the vicinity of the heat exchanger is stopped.

  In the refrigerant circuit device according to claim 3 of the present invention, in the above-described claim 1, in the case where the control means performs a single heating operation, the refrigerant circuit device inflows the refrigerant that has passed through the heating side heat exchanger. The internal blower fan disposed in the vicinity of the heat exchanger is driven to rotate in the direction opposite to the normal time.

  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 bypass valve provided in the refrigerant circuit device opens and passes through the heating side heat exchanger. The control means includes a bypass path for supplying the refrigerant to the compressor, and the control means determines in advance a condensing temperature of the internal heat exchanger to which the refrigerant is supplied through the high-pressure refrigerant introduction path when performing a single heating operation. When the reference temperature is exceeded, the bypass valve is closed and the refrigerant that has passed through the heating side heat exchanger is caused to flow into an in-compartment heat exchanger disposed outside the chamber to be heated, When the condensation temperature is equal to or lower than the reference temperature, the bypass valve is opened.

  According to the refrigerant circuit device of the present invention, when the control means performs the heating single operation, the return valve is closed, and the refrigerant that has passed through the heating-side heat exchanger is disposed outside the chamber to be heated. Since it is made to flow in into the done heat exchanger in a warehouse, the piping volume of a refrigerant circuit can be increased. Thereby, even if the amount of refrigerant sealed in the refrigerant circuit corresponds to the necessary amount for the cooling heating operation, the amount of refrigerant in the path from the compressor of the refrigerant circuit to the internal heat exchanger of the chamber to be heated Can be relatively reduced, the pressure in the route is prevented from excessively rising, and there is no possibility of causing damage to the device. Therefore, even if the amount of refrigerant in the refrigerant circuit corresponds to the required amount for the cooling and heating operation, there is an effect that the heating alone operation can be performed satisfactorily by preventing an excessive increase in pressure.

FIG. 1 is a sectional view showing a case where an internal structure of a vending machine to which a refrigerant circuit device according to an embodiment of the present invention is applied is viewed from the front. 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. FIG. 3 is a conceptual diagram conceptually showing the refrigerant circuit device applied to the vending machine shown in FIGS. 1 and 2. FIG. 4 is a block diagram schematically showing a characteristic control system of the refrigerant circuit device shown in FIG. FIG. 5 is a conceptual diagram showing the flow of the refrigerant when performing the cooling heating operation (HCC operation) in the refrigerant circuit device shown in FIG. 3. FIG. 6 is a conceptual diagram illustrating the flow of the refrigerant when the single heating operation is performed in the refrigerant circuit device illustrated in FIG. 3. FIG. 7 is a flowchart showing the processing contents of the refrigerant flow path control processing executed by the controller in the heating single operation shown in FIG. FIG. 8 is a conceptual diagram showing the flow of the refrigerant by performing the process shown in FIG.

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

  FIG. 1 is a sectional view showing a case where an internal structure of a vending machine to which a refrigerant circuit device according to an embodiment 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 them at 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 product storage case 3. Here, the internal structure of the right product storage 3 (hereinafter also referred to as the right storage 3a) is shown, but 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 product storage 3 is provided with a product 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 the refrigerant circuit device applied to the vending machine shown in FIGS. 1 and 2, and FIG. 4 is a characteristic control system of the refrigerant circuit device shown in FIG. It is a block diagram which shows typically. The refrigerant circuit device illustrated here includes a refrigerant circuit 10 having a main path 20, a high-pressure refrigerant introduction path 30, a first return path 40, and a second return path 50. The refrigerant circuit 10 has a refrigerant (for example, R134a) sealed therein.

  The main path 20 is configured by sequentially connecting a compressor 21, an external heat exchanger 22, and an internal heat exchanger 24 through a refrigerant pipe 25.

  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 external heat exchanger 22 is disposed in the machine room 9 similarly to the compressor 21. When the refrigerant | coolant compressed with the compressor 21 passes, this external heat exchanger 22 condenses this refrigerant | coolant.

  A three-way valve 261 is provided in the refrigerant pipe 25 that connects the external heat exchanger 22 and the compressor 21. The three-way valve 261 will be described later.

  A plurality of (three in the illustrated example) heat exchangers 24 in the cabinet are provided, which are disposed in the lower interior of each commodity storage 3 and on the front side of the rear duct D (see FIG. 2). is there. The refrigerant pipe 25 connecting the internal heat exchanger 24 and the external heat exchanger 22 is branched at a first branch point P1 in the middle of the internal heat exchanger 24 and the internal heat exchanger 24 disposed in the right warehouse 3a. On the entrance side of the internal heat exchanger 24 (hereinafter also referred to as the internal heat exchanger 24b) disposed in the internal storage 3b on the entrance side of the right internal heat exchanger 24a (hereinafter also referred to as the internal internal heat exchanger 24b) It is connected to the inlet side of the internal heat exchanger 24 (hereinafter also referred to as the left internal heat exchanger 24c) disposed inside the left warehouse 3c.

  Further, in this refrigerant pipe 25, expansion mechanisms 231, 232,... On the way from the first branch point P1 to each of the right internal heat exchanger 24a, the central internal heat exchanger 24b, and the left internal heat exchanger 24c. 233 is provided. The expansion mechanisms 231, 232, and 233 are variable in flow rate that can adjust the opening according to a command given from the controller 80, and can be in a fully closed state. The expansion mechanisms 231, 232, and 233 are for adiabatic expansion by reducing the pressure of the passing refrigerant.

  The refrigerant piping 25 connected to the outlet side of the internal heat exchanger 24 joins at the first joining point P <b> 2 in the middle, and is connected to the compressor 21 via the accumulator 27. Here, the accumulator 27 is gas-liquid separation means for storing the liquid-phase refrigerant and allowing the gas-phase refrigerant to pass through when the passing refrigerant is a gas-liquid mixed refrigerant. Note that outlet-side low-pressure solenoid valves 262b and 262c are arranged in the middle of the refrigerant pipe 25 from the outlet side of the inner-chamber heat exchanger 24b and the left-chamber heat exchanger 24c to the first junction P2. The outlet-side low-pressure solenoid valves 262b and 262c are openable and closable valve bodies. When the opening command is given from the controller 80, the outlet-side low-pressure solenoid valves 262b and 262c are opened to allow passage of the refrigerant, while when the closing command is given. Is closed to restrict the passage of refrigerant.

  In such a main path 20, reference numeral 28 in FIG. 3 is an internal heat exchanger. The internal heat exchanger 28 exchanges heat between the high-pressure refrigerant and the low-pressure refrigerant.

  The high-pressure refrigerant introduction path 30 is connected to the three-way valve 261 and branches in the middle, one of which is connected to the refrigerant pipe 25 on the inlet side of the internal heat exchanger 24b and the other is the inlet of the left internal heat exchanger 24c. It is the path | route comprised by the high voltage | pressure refrigerant | coolant inlet piping 31 each joined to the refrigerant | coolant piping 25 of the side. The high-pressure refrigerant introduction path 30 is a path for introducing the refrigerant (high-pressure refrigerant) compressed by the compressor 21.

  Here, the three-way valve 261 is a first sending state in which the refrigerant compressed by the compressor 21 is sent to the external heat exchanger 22 and a second sending state in which the refrigerant compressed by the compressor 21 is sent to the high-pressure refrigerant introduction path 30. It is a switching valve that can be switched alternatively between. The switching operation of the three-way valve 261 is performed according to a command given from the controller 80.

  In the high-pressure refrigerant introduction pipe 31, high-pressure introduction valves 321 and 322 are provided on the downstream side of the branch point, respectively. The high-pressure introduction valves 321 and 322 are valve bodies that can be opened and closed. When the opening command is given from the controller 80, the high-pressure introduction valves 321 and 322 are opened and allow the refrigerant to pass therethrough. Thus, the passage of the refrigerant is restricted.

  That is, when the refrigerant compressed by the compressor 21 is supplied through the high-pressure refrigerant introduction path 30, the inner-compartment heat exchanger 24 b and the left-compartment heat exchanger 24 c It heats the internal air of the product storage 3 (the central storage 3b and the left storage 3c).

  The first return path 40 is branched in the middle of each of the refrigerant pipes 25 connected to the outlet side of the internal heat exchanger 24b and the left internal heat exchanger 24c, and merges at the second junction P3. This is a path constituted by the first return pipe 41 connected to the inlet side of the heating side heat exchanger 42 arranged in a mode adjacent to the external heat exchanger 22. The first return path 40 is for supplying the refrigerant condensed in at least one of the internal heat exchanger 24 b and the left internal heat exchanger 24 c to the heating side heat exchanger 42.

  The heating-side heat exchanger 42 is disposed in a manner adjacent to the external heat exchanger 22 and exchanges heat between the refrigerant passing therethrough and the ambient air. That is, the first return path 40 introduces the refrigerant condensed in the internal heat exchanger 24 and supplies it to the heating side heat exchanger 42.

  From a branch point with the refrigerant pipe 25 connected to the outlet side of the middle return heat exchanger 24b and the left return heat exchanger 24c in the middle of the first return pipe 41 constituting the first return path 40. On the way to the second junction P3, check valves 431 and 432 are provided, respectively.

  The first return path 40 is provided with a return valve 44 and a branch path 45. The return valve 44 is provided in the middle of the first return pipe 41. The return valve 44 is a valve body that can be opened and closed. When the opening command is given from the controller 80, the return valve 44 opens and allows the refrigerant to pass therethrough, but closes when the closing command is given. It regulates the passage of refrigerant.

  The branch path 45 is connected in a manner that branches from a branch point upstream of the return valve 44 in the first return pipe 41 and joins at a junction point downstream of the return valve 44 in the first return pipe 41. The branch pipe 46 is provided with a branch expansion mechanism 47.

  The branch expansion mechanism 47 can adjust the opening degree according to a command given from the controller 80, and can be in a fully closed state. The branch expansion mechanism 47 is for adiabatic expansion by reducing the pressure of the refrigerant passing therethrough.

  The second return path 50 is connected to the outlet side of the heating side heat exchanger 42 and is connected to the refrigerant pipe 25 constituting the main path 20, that is, the external heat exchanger 22 (in the illustrated example, the internal heat exchanger 28). The second return pipe 51 is connected to the third junction P4 of the refrigerant pipe 25 between the first branch point P1. The second return path 50 is for introducing the refrigerant that has passed through the heating side heat exchanger 42 and returning it to the upstream side of the in-compartment heat exchanger 24 of the main path 20. It is arranged. The capillary tube 52 decompresses the refrigerant passing through the second return pipe 51 and adiabatically expands the refrigerant.

  The refrigerant circuit 10 having the above configuration includes a first bypass path 60 and a second bypass path 70 in addition to the above configuration.

  The first bypass path 60 branches off from a branch point in the middle of the second return pipe 51 from the heating side heat exchanger 42 to the capillary tube 52, and is in the middle of the refrigerant pipe 25 between the internal heat exchanger 28 and the accumulator 27. It is comprised by the 1st bypass piping 61 provided in the aspect which merges. Such a first bypass pipe 61 is provided with a first bypass valve 62. The first bypass valve 62 is a valve body that can be opened and closed. The first bypass valve 62 is opened when the opening command is given from the controller 80 and allowed to pass through the refrigerant. On the other hand, the first bypass valve 62 is closed when the closing command is given. This restricts the passage of refrigerant.

  The second bypass path 70 branches off from a branch point in the middle of the refrigerant pipe 25 extending from the external heat exchanger 22 to the internal heat exchanger 28, and the refrigerant pipe 25 extending from the first junction P <b> 2 to the internal heat exchanger 28. It is comprised by the 2nd bypass piping 71 provided in the aspect which merges in the middle merge point. Such a second bypass pipe 71 is provided with a second bypass valve 72. The second bypass valve 72 is a valve body that can be opened and closed. When the opening command is given from the controller 80, the second bypass valve 72 opens and allows the refrigerant to pass therethrough, but when the closing command is given, the second bypass valve 72 closes. This restricts the passage of refrigerant.

  Next, the control system of the refrigerant circuit device will be described. As shown in FIG. 4, the refrigerant circuit device according to the present embodiment includes a condensation temperature sensor S <b> 1 and a controller 80.

  The condensation temperature sensor S1 is connected to the high-pressure refrigerant introduction pipe 31 in the vicinity of the inlet side of the internal heat exchanger 24 (the internal internal heat exchanger 24b and the left internal heat exchanger 24c) disposed in the chamber to be heated. It is arranged. The condensing temperature sensor detects the refrigerant temperature entering the internal heat exchanger 24, and the detected refrigerant temperature is sent to the controller 80 as a condensed refrigerant temperature signal.

  The controller 80 controls driving of the compressor 21, various valves (including the expansion mechanisms 231 to 233 and 47), the internal blower fan F1, and the like according to data and programs stored in a built-in memory not explicitly shown in the figure. Is.

  The refrigerant circuit device having the above-described configuration cools or heats the product stored in the product storage 3 as follows.

  First, the case where the HCC operation (cooling heating operation for heating the internal air of the left warehouse 3c and cooling the internal air of the right warehouse 3a and the middle warehouse 3b) is described. In this case, the controller 80 puts the three-way valve 261 in the second delivery state, fully closes the expansion mechanism 233, and turns the outlet-side low-pressure solenoid valve 262c, the high-pressure introduction valve 321, the first bypass valve 62, and the second bypass valve 72. The outlet side low-pressure solenoid valve 262b, the high-pressure introduction valve 322, and the return valve 44 are opened by closing the expansion mechanisms 231 and 232 to a desired size. As a result, the refrigerant compressed by the compressor 21 circulates as shown in FIG.

  In other words, the refrigerant compressed by the compressor 21 flows into the high-pressure refrigerant introduction pipe 31 via the three-way valve 261 in the second delivery state, passes through the high-pressure refrigerant introduction pipe 31 and passes through the left-side heat exchanger. 24c. The refrigerant that has reached the left internal heat exchanger 24c exchanges heat with the internal air of the left internal 3c while passing through the heat exchanger, and dissipates heat to the internal air to condense. Thereby, the internal air of the left warehouse 3c is heated. The heated internal air circulates inside each of the left warehouses 3c by driving the internal blower fan F1, whereby the products stored in the left warehouse 3c are heated to the circulating internal air.

  The refrigerant condensed in the left-side heat exchanger 24c reaches the heating-side heat exchanger 42 via the return valve 44 that opens through the first return pipe 41 that constitutes the first return path 40.

  The refrigerant that has passed through the heating-side heat exchanger 42 passes through the second return pipe 51, adiabatically expands in the capillary tube 52, flows into the main path 20 from the third junction P4, and the opening degree becomes a desired size. It passes through the adjusted expansion mechanisms 231 and 232, and further adiabatically expands. The refrigerant that has passed through the expansion mechanisms 231 and 232 reaches the right internal heat exchanger 24a and the internal heat exchanger 24b, and evaporates in the right internal heat exchanger 24a and the internal heat exchanger 24b, respectively. Then, heat is taken from the internal air of each product container 3 to cool the internal air. The cooled internal air circulates inside each product storage 3 by driving each internal blower fan F1, thereby cooling the products stored in each product storage 3 (right store 3a and middle store 3b). Is done. The refrigerant evaporated in the right internal heat exchanger 24a and the internal internal heat exchanger 24b is sucked into the compressor 21 through the accumulator 27, is compressed by the compressor 21, and repeats the circulation described above.

  Next, the case of performing the heating single operation (here, the operation of heating the internal air of only the left warehouse 3c) will be described. In this case, the controller 80 causes the three-way valve 261 to be in the second delivery state, fully closes the expansion mechanisms 231, 232, 233, the outlet side low pressure solenoid valves 262b, 262c, the high pressure introduction valve 321, the return valve 44, and the second The bypass valve 72 is closed, and the high-pressure introduction valve 322, the branch expansion mechanism 47, and the first bypass valve 62 are opened. As a result, the refrigerant compressed by the compressor 21 circulates as shown in FIG.

  In other words, the refrigerant compressed by the compressor 21 flows into the high-pressure refrigerant introduction pipe 31 via the three-way valve 261 in the second delivery state, passes through the high-pressure refrigerant introduction pipe 31 and passes through the left-side heat exchanger. 24c. The refrigerant that has reached the left-side internal heat exchanger 24c exchanges heat with the internal air of the left-side 3c while passing through the left-side internal heat exchanger 24c, and dissipates and condenses the internal air. Become. Thereby, the internal air of the left warehouse 3c is heated. The heated internal air circulates inside each of the left warehouses 3c by driving the internal blower fan F1, whereby the products stored in the left warehouse 3c are heated to the circulating internal air.

  The refrigerant condensed in the left-side internal heat exchanger 24 c passes through the first return pipe 41 constituting the first return path 40 and reaches the branch pipe 46. The refrigerant passing through the branch pipe 46 is adiabatically expanded by the branch expansion mechanism 47. The adiabatically expanded refrigerant flows into the heating side heat exchanger 42.

  The refrigerant that has passed through the heating-side heat exchanger 42 passes through the first bypass pipe 61 via the second return pipe 51, and gradually evaporates by exchanging heat with the outside air during the passage. It changes from a gas-liquid two-phase state to a gas phase state. Then, gas-liquid separation is performed by the accumulator 27, and the gas-phase refrigerant is sucked into the compressor 21 and compressed by the compressor 21 to repeat the above-described circulation. FIG. 7 is a flowchart showing the processing contents of the refrigerant flow path control processing executed by the controller in the heating single operation shown in FIG.

  When the controller 80 inputs the condensation temperature, which is the detected temperature, from the condensation temperature sensor S1 disposed in the vicinity of the inlet side of the left-side heat exchanger 24c (step S101: Yes), the condensation temperature is previously stored in the built-in memory. It is determined whether or not the stored reference temperature is exceeded (step S102).

  When the condensation temperature is equal to or lower than the reference temperature (step S102: No), the controller 80 does not execute the following process, that is, maintains the opening of the first bypass valve 62, and then returns the procedure to this time. Terminate the process.

  On the other hand, when the condensation temperature exceeds the reference temperature (step S102: Yes), the controller 80 opens the expansion mechanism 232 at a predetermined opening, opens the outlet-side low-pressure electromagnetic valve 262b, and further The bypass valve 62 is closed (step S103, step S104). Furthermore, the controller 80 maintains the drive stop of the internal blower fan F1 in the internal storage 3b (step S105), and then returns the procedure to end the current process.

  According to this, the refrigerant circulates as shown in FIG. That is, the refrigerant that has passed through the heating-side heat exchanger 42 flows into the main path 20 via the second return pipe 51, passes through the expansion mechanism 232 whose opening degree is adjusted to a desired size, and is further insulated. Inflate. The refrigerant that has passed through the expansion mechanism 232 flows into the internal heat exchanger 24b, is then sucked into the compressor 21 through the accumulator 27, is compressed by the compressor 21, and repeats the circulation described above.

  In the refrigerant circuit device according to the present embodiment as described above, when the heating single operation is performed, the refrigerant that has passed through the heating side heat exchanger 42 according to the condensing temperature is to be heated. Since the refrigerant flows into the internal heat exchanger 24b disposed in the product storage 3b other than the product storage 3, the piping volume during the heating single operation in the refrigerant circuit 10 can be increased. As a result, even if the amount of refrigerant sealed in the refrigerant circuit 10 corresponds to the required amount for the cooling and heating operation, the refrigerant circuit 10 is compressed by increasing the pipe volume during the heating independent operation in the refrigerant circuit 10. The amount of refrigerant in the path from the machine 21 to the internal heat exchanger 24 (the left internal heat exchanger 24c) of the room to be heated can be relatively reduced, and the pressure in the path excessively increases. And there is no risk of equipment damage.

  Therefore, according to the refrigerant circuit device according to the present embodiment, even if the amount of refrigerant in the refrigerant circuit 10 corresponds to the required amount for the cooling and heating operation, it is possible to prevent the pressure from rising excessively and perform the heating only operation. Can be done.

  In particular, since the refrigerant flow path during heating independent operation is controlled according to the condensation temperature, the refrigerant amount distribution can be adjusted without being affected by the ambient temperature, etc., and the optimum refrigerant amount distribution according to the operation pattern can be obtained. As a result, the operating efficiency can be improved and a desired condensation temperature can be obtained.

  Moreover, according to the said refrigerant circuit apparatus, the drive of the internal ventilation fan F1 arrange | positioned in the vicinity of the internal heat exchanger 24b into which a refrigerant | coolant flows in at the time of heating independent operation is stopped (a drive stop is maintained). Therefore, it can avoid making the internal temperature of the store | warehouse | chamber 3b into a supercooled state, and generation | occurrence | production of goods freeze etc. can be suppressed.

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to this, and various modifications can be made.

  In the above-described embodiment, the flow of the refrigerant during the heating single operation is controlled according to the condensing temperature. However, in the present invention, the room to be heated (commodity storage box) during the heating single operation regardless of the condensation temperature. The refrigerant may be allowed to flow into an internal heat exchanger (such as the internal heat exchanger 24b) disposed in a chamber other than 3).

  Further, in the above-described embodiment, the controller 80 stops driving the internal fan F1 disposed in the vicinity of the internal heat exchanger 24b through which the refrigerant flows, but in the present invention, the controller 80 The internal blower fan may be driven to rotate in the direction opposite to the normal time. Also by this, it can avoid making the inside temperature into a supercooled state, generation | occurrence | production of goods freezing etc. can be suppressed, and also the frost formation to the said internal heat exchanger can be suppressed.

  In the above-described embodiment, the capillary tube 52 is provided in the second return pipe 51 and adiabatic expansion is performed by the capillary tube 52. However, in the present invention, the capillary tube of the return pipe is not an essential component. Adiabatic expansion may be performed by an expansion mechanism provided on the upstream side of each internal heat exchanger.

  In the embodiment described above, the internal heat exchanger 28 is provided. However, in the present invention, the internal heat exchanger may not be provided.

  As described above, the refrigerant circuit device according to the present invention is useful for vending machines that sell products such as canned beverages and plastic bottled beverages.

DESCRIPTION OF SYMBOLS 1 Main body cabinet 10 Refrigerant circuit 20 Main path 21 Compressor 22 External heat exchanger 231 Expansion mechanism 232 Expansion mechanism 233 Expansion mechanism 24 Internal heat exchanger 24a Right internal heat exchanger 24b Central internal heat exchanger 24c Left warehouse Internal heat exchanger 25 Refrigerant pipe 261 Three-way valve 262b Outlet side low pressure solenoid valve 262c Outlet side low pressure solenoid valve 30 High pressure refrigerant introduction path 31 High pressure refrigerant introduction pipe 321 High pressure refrigerant introduction valve 322 High pressure introduction valve 40 First return path 41 First return pipe 42 Heating Side Heat Exchanger 44 Return Valve 45 Branch Path 46 Branch Pipe 47 Expansion Mechanism 50 Second Return Path 51 Second Return Pipe 52 Capillary Tube 60 First Bypass Path 61 First Bypass Pipe 62 First Bypass Valve 70 Second Bypass Route 71 Second bypass pipe 72 Second bypass valve 80 Control -Fla F1 Internal fan F2 External fan S1 Condensation temperature sensor

Claims (4)

An internal heat exchanger disposed inside the target chamber, a compressor that sucks and compresses the refrigerant that has passed through the internal heat exchanger, and external heat exchange that condenses the refrigerant compressed by the compressor A main path configured by sequentially connecting the vessel with refrigerant piping,
By introducing the refrigerant compressed by the compressor by opening an introduction valve provided in itself, and supplying the refrigerant disposed in the chamber to be heated among the internal heat exchangers, A high-pressure refrigerant introduction path for condensing the refrigerant in the internal heat exchanger;
A return path for returning the refrigerant condensed in the internal heat exchanger to the upstream side of the internal heat exchanger in the main path through the heating side heat exchanger;
A refrigerant provided in at least one of the main path and the return path, and an expansion mechanism that adiabatically expands either the refrigerant condensed in the external heat exchanger or the refrigerant that has passed through the heating side heat exchanger In the circuit device,
It is arranged in the middle of the pipe from the internal heat exchanger to the heating side heat exchanger, and allows the refrigerant to flow from the internal heat exchanger to the heating side heat exchanger when it opens. On the other hand, a return valve that restricts the flow of refrigerant from the internal heat exchanger to the heating-side heat exchanger when it is closed,
When the return valve is closed, a branch path that introduces the refrigerant condensed in the internal heat exchanger and adiabatically expands and supplies it to the heating side heat exchanger;
Control means for closing the return valve and causing the refrigerant that has passed through the heating side heat exchanger to flow into an in-compartment heat exchanger disposed outside the chamber to be heated in the case of performing heating single operation A refrigerant circuit device comprising:   The control means, when performing a single heating operation, stops driving the internal blower fan disposed in the vicinity of the internal heat exchanger through which the refrigerant that has passed through the heating side heat exchanger flows. The refrigerant circuit device according to claim 1.   In the case of performing the heating single operation, the control means causes the internal blower fan disposed in the vicinity of the internal heat exchanger that allows the refrigerant that has passed through the heating side heat exchanger to flow in a direction opposite to the normal time. The refrigerant circuit device according to claim 1, wherein the refrigerant circuit device is driven to rotate. The bypass valve provided in itself opens and introduces the refrigerant that has passed through the heating-side heat exchanger, and includes a bypass path that supplies the compressor,
The control means closes the bypass valve when performing a single heating operation and the condensation temperature of the internal heat exchanger to which the refrigerant is supplied through the high-pressure refrigerant introduction path exceeds a predetermined reference temperature. The refrigerant that has passed through the heating-side heat exchanger is caused to flow into an in-compartment heat exchanger that is disposed outside the chamber to be heated. The refrigerant circuit device according to claim 1, wherein the refrigerant circuit device is used.

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