Refrigerant circuit device

Abstract

To achieve reduction in power consumption.SOLUTION: A refrigerant circuit device includes a refrigerant circuit 10 having a circulation path 20 constituted by sequentially connecting an inside heat exchanger 24, a compressor 21, an outside heat exchanger 22, and an expansion mechanism 23 by a refrigerant conduit 25; an introduction path 30 for supplying a refrigerant discharged from the compressor 21 with respect to the inside heat exchanger 24 of a heating chamber; and a return path 40 for supplying the refrigerant to the upstream side of the outside heat exchanger 22. The refrigerant circuit device also includes a control part 60 which drives the compressor 21 in the case where a temperature in the heating chamber becomes equal to or lower than a heating ON temperature, and which stops the drive of the compressor 21 in the case where the temperature in the heating chamber becomes equal to or higher than the heating OFF temperature. The control part performs compressor on-off control for maintaining the drive stop of the compressor 21 until the temperature in the heating chamber becomes equal to or lower than the heating ON temperature in the case where the temperature in a cooling chamber is equal to or higher than a cooling ON temperature but it is in a cooling ON delay temperature range, and for maintaining the drive of the compressor 21 until the temperature in the heating chamber becomes equal to or higher than the heating OFF temperature, in the case where the temperature in the cooling chamber is equal to or lower than a cooling OFF temperature but it is within a cooling OFF delay temperature range.SELECTED DRAWING: Figure 3

Description

TECHNICAL FIELD

[0001] The present invention relates to a refrigerant circuit device, and more particularly to a refrigerant circuit device applied to, for example, a vending machine, for cooling and / or heating the internal atmosphere of a product storage compartment with a heat insulating structure defined in a vending machine body. BACKGROUND ART

[0002] Conventionally, as a refrigerant circuit device applied to, for example, a vending machine, one provided with a refrigerant circuit having a function as a heat pump is known. Such a refrigerant circuit includes a first path, a second path and a third path.

[0003] The first path is formed in an annular shape by sequentially connecting an internal heat exchanger, a compressor, an external heat exchanger and an expansion mechanism via refrigerant pipes. The internal heat exchanger is disposed inside the product storage compartment of the vending machine. The internal heat exchanger performs heat exchange between the supplied refrigerant and the internal air (internal atmosphere) of the product storage compartment when the supplied refrigerant passes through a predetermined flow path.

[0004] The compressor is disposed in a machine room inside the vending machine body and outside the product storage compartment, sucks the refrigerant from the internal heat exchanger, compresses the sucked refrigerant into a high-temperature and high-pressure state, and discharges the same. Like the compressor, the external heat exchanger is disposed in the machine room, and performs heat exchange between the supplied refrigerant and ambient air when the supplied refrigerant passes through a predetermined flow path, so as to radiate heat from the refrigerant. The expansion mechanism adiabatically expands the refrigerant that has radiated heat in the external heat exchanger by increasing or decreasing the flow rate of the refrigerant.

[0005] In such a first path, the refrigerant compressed by the compressor radiates heat in the external heat exchanger, the radiated refrigerant is adiabatically expanded by the expansion mechanism, and evaporates by exchanging heat with the internal air of the product storage compartment in the internal heat exchanger. The refrigerant evaporated in the internal heat exchanger is sucked by the compressor, compressed again and circulated. Accordingly, the internal air in the product storage compartment where the internal heat exchanger is disposed is cooled.

[0006] The second path introduces a refrigerant compressed by a compressor and supplies it to the internal heat exchanger (heated internal heat exchanger) located in the product storage compartment to be heated, which is one of the internal heat exchangers that make up the first path. This causes the refrigerant to release heat in the heated internal heat exchanger. As a result, the internal air in the product storage compartment where the heated internal heat exchanger is located is heated.

[0007] The third path introduces the refrigerant that has released heat in the internal heat exchanger of the heating chamber and returns it to the upstream side of the external heat exchanger in the first path. As a result, the refrigerant that has passed through the third path reaches the first path, where it releases heat in the external heat exchanger, and then undergoes adiabatic expansion by the expansion mechanism before being sent to the internal heat exchanger.

[0008] In a refrigerant circuit device with such a configuration, when only cooling the internal air of a particular product storage container is required (cooling-only operation), the refrigerant only needs to be circulated through the first path. On the other hand, when heating the internal air of one product storage container to cool the internal air of another product storage container (cooling and heating operation), high-pressure refrigerant should be supplied through the second path to the heat exchanger inside the heating chamber of the product storage container to be heated to dissipate heat, and then circulated back to the first path via the third path and sent to the heat exchanger inside the product storage container to be cooled.

[0009] In the above-described refrigerant circuit device, the compressor is driven as follows when performing cooling and heating operations. Specifically, the compressor is driven when the internal temperature of the product storage area to be cooled (cooling area) exceeds a predetermined cooling-on temperature, or when the internal temperature of the product storage area to be heated (heating area) falls below a predetermined heating-on temperature. Conversely, the compressor is stopped when the internal temperature of the cooling area falls below a predetermined cooling-off temperature, or when the internal temperature of the heating area rises above the heating-off temperature (see, for example, Patent Document 1). [Prior art documents] [Patent Documents]

[0010] [Patent Document 1] Japanese Patent Publication No. 2003-173467 [Overview of the Initiative] [Problems that the invention aims to solve]

[0011] Incidentally, in the above-mentioned refrigerant circuit device, if there are multiple coolers, it is thought that in order to reduce power consumption, the compressor is driven to cool the internal air of each cooler when the internal temperature of all coolers exceeds the cooling-on temperature. Furthermore, because it is difficult to control the temperature of the products stored in the heating chamber, it is thought that the compressor is driven even when the internal temperature of the heating chamber falls below the heating-on temperature, regardless of the internal temperature of the coolers.

[0012] Therefore, in the refrigerant circuit system described above, the compressor was driven not only when the internal temperature of all cooling chambers was above the cooling-on temperature, but also when the internal temperature of any heating chamber fell below the heating-on temperature. As a result, the compressor was operating at a high rate, which ultimately led to increased power consumption.

[0013] In view of the above circumstances, the present invention aims to provide a refrigerant circuit device that can reduce power consumption. [Means for solving the problem]

[0014] To achieve the above objective, the refrigerant circuit device according to the present invention has a refrigerant circuit comprising: a first path configured by sequentially connecting an internal heat exchanger disposed inside the chamber, a compressor that sucks in and compresses the refrigerant that has passed through the internal heat exchanger, an external heat exchanger disposed outside the chamber, and an expansion mechanism that increases or decreases the flow rate of the refrigerant that has passed through the external heat exchanger to cause adiabatic expansion via a refrigerant pipeline; a second path that supplies the refrigerant compressed by the compressor to a heating chamber heat exchanger disposed in the heating chamber to be heated, when refrigerant is introduced by a switching valve provided in the refrigerant pipeline on the discharge side of the compressor; and a third path that supplies the refrigerant that has passed through the heating chamber heat exchanger to the upstream side of the external heat exchanger in the first path, and by circulating the refrigerant in the refrigerant circuit, the internal atmosphere of the heating chamber is heated while the heating chamber heat exchanger A refrigerant circuit device for cooling the internal atmosphere of any cooling chamber in which a heat exchanger other than a refrigerant is installed, comprising a control unit that drives the compressor when the internal temperature of the heating chamber falls below a predetermined heating on temperature, and stops the compressor when the internal temperature of the heating chamber rises above a predetermined heating off temperature, wherein the control unit maintains the compressor's deactivation until the internal temperature of the heating chamber falls below the heating on temperature if the internal temperature of the cooling chamber is above a predetermined cooling on temperature but within a cooling on grace temperature range, and maintains the compressor's operation until the internal temperature of the heating chamber rises above the heating off temperature if the internal temperature of the cooling chamber is below a predetermined cooling off temperature but within a cooling off grace temperature range, thereby performing compressor on / off control.

[0015] Furthermore, the present invention is characterized in that, in the above-mentioned refrigerant circuit device, the control unit reduces the flow rate of the refrigerant in the expansion mechanism when the intermediate temperature of the temperature difference between the temperature of the cooling chamber when the compressor is driven and the temperature of the cooling chamber when the compressor is stopped is higher than a preset target temperature, while increasing the flow rate of the refrigerant in the expansion mechanism when the intermediate temperature is lower than the target temperature, thereby performing evaporation temperature control.

[0016] Furthermore, the present invention provides the above-mentioned refrigerant circuit device, wherein the third path includes an expansion valve that increases or decreases the flow rate of the refrigerant passing through it to adiabatically expand the refrigerant, and the control unit performs intermediate pressure control such that when the intermediate temperature of the temperature difference between the temperature of the cooling chamber when the compressor is driven and the temperature of the cooling chamber when the compressor is stopped is higher than a preset target temperature, the flow rate of the refrigerant in the expansion valve is increased, while when the intermediate temperature is lower than the target temperature, the flow rate of the refrigerant in the expansion valve is reduced.

[0017] Furthermore, the present invention is characterized in that, in the above-mentioned refrigerant circuit device, the second path is provided in such a manner that it branches off from the refrigerant pipeline connecting the compressor and the external heat exchanger and merges with the refrigerant pipeline connecting the expansion mechanism and the internal heat exchanger of the heating chamber, and the third path is provided in such a manner that it branches off from the refrigerant pipeline connecting the internal heat exchanger of the heating chamber and the compressor and merges with the refrigerant pipeline connecting the compressor and the external heat exchanger. [Effects of the Invention]

[0018] According to the present invention, the control unit drives the compressor when the internal temperature of the heating chamber falls below a predetermined heating on temperature, and stops the compressor when the internal temperature of the heating chamber rises above a predetermined heating off temperature. However, if the internal temperature of the cooling chamber is above a predetermined cooling on temperature but within the cooling on grace temperature range, the control unit maintains the compressor off until the internal temperature of the heating chamber falls below the heating on temperature. Conversely, if the internal temperature of the cooling chamber is below a predetermined cooling off temperature but within the cooling off grace temperature range, the control unit maintains the compressor drive until the internal temperature of the heating chamber rises above the heating off temperature. This compressor on / off control prioritizes the internal temperature of the heating chamber, where temperature control of stored goods is difficult, while reducing the number of times the compressor is driven, thereby reducing power consumption. [Brief explanation of the drawing]

[0019] [Figure 1]Figure 1 is a cross-sectional view showing the internal structure of a vending machine to which the refrigerant circuit device according to the first embodiment of the present invention is applied, as viewed from the front. [Figure 2] Figure 2 shows the internal structure of the vending machine shown in Figure 1, and is a cross-sectional side view of the product storage compartment on the right side. [Figure 3] Figure 3 is a conceptual diagram conceptually showing the refrigerant circuit device according to the first embodiment of the present invention. [Figure 4] Figure 4 is a conceptual diagram showing the flow of refrigerant when performing CCC operation in the refrigerant circuit shown in Figure 3. [Figure 5] Figure 5 is a conceptual diagram showing the flow of refrigerant when performing HCC operation in the refrigerant circuit shown in Figure 3. [Figure 6] Figure 6 is a time chart for explaining the compressor on-off control implemented by the control unit shown in Figure 2. [Figure 7] Figure 7 is a flowchart showing the processing content of evaporation temperature control performed separately from the compressor on-off control in cooling and heating operation (HCC operation) by the control unit shown in Figure 2. [Figure 8] Figure 8 is a conceptual diagram conceptually showing the refrigerant circuit device according to the second embodiment of the present invention. [Figure 9] Figure 9 is a conceptual diagram showing the flow of refrigerant when performing CCC operation in the refrigerant circuit shown in Figure 8. [Figure 10] Figure 10 is a conceptual diagram showing the flow of refrigerant when performing HCC operation in the refrigerant circuit shown in Figure 8. [Figure 11] Figure 11 is a flowchart showing the processing content of intermediate pressure control performed separately from the compressor on-off control in cooling and heating operation (HCC operation) by the control unit shown in Figure 8. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, with reference to the accompanying drawings, preferred embodiments of the refrigerant circuit device according to the present invention will be described in detail.

[0021] <Embodiment 1> Figure 1 is a cross-sectional view of the internal structure of a vending machine to which a refrigerant circuit device according to Embodiment 1 of the present invention is applied, viewed from the front. The vending machine illustrated here comprises a main cabinet 1.

[0022] The main cabinet 1 has a rectangular shape with an opening at the front. Inside this main cabinet 1, there are three independent product storage compartments 3 arranged on the left and right sides, each partitioned by, for example, two insulating partition plates 2. These product storage compartments 3 are rooms for storing products such as beverages in containers such as cans or plastic bottles while maintaining them at a desired temperature, and have an insulating structure.

[0023] Figure 2 shows the internal structure of the vending machine shown in Figure 1, and is a cross-sectional side view of the right-side product storage compartment 3. While this description focuses on the internal structure of the right-side product storage compartment 3 (hereinafter also referred to as right compartment 3a), the internal structures of the central product storage compartment 3 (hereinafter also referred to as middle compartment 3b) and the left-side product storage compartment 3 (hereinafter also referred to as left compartment 3c) are substantially similar to those of right compartment 3a. In this specification, "right side" refers to the right when the vending machine is viewed from the front, and "left side" refers to the left when the vending machine is viewed from the front.

[0024] As shown in Figure 2, the main cabinet 1 is provided with an outer door 4 and an inner door 5 on its front. The outer door 4 is for opening and closing the front opening of the main cabinet 1, and the inner door 5 is for opening and closing the front of the product storage compartment 3. This inner door 5 is divided into upper and lower sections, and the upper door 5a is opened and closed when replenishing products.

[0025] The above-mentioned product storage unit 3 is equipped with a storage rack 6, a loading mechanism 7, and a loading chute 8. The storage rack 6 is for storing products in an arrangement that runs vertically. The loading mechanism 7 is located at the bottom of the storage rack 6 and is for loading out the products at the bottom of the product group stored in the storage rack 6 one by one. The loading chute 8 is for guiding the products loaded out from the loading mechanism 7 to the product retrieval opening 4a provided in the outer door 4.

[0026] Figure 3 is a conceptual diagram showing a refrigerant circuit device according to Embodiment 1 of the present invention. The refrigerant circuit device illustrated here comprises a refrigerant circuit 10 having a circulation path (first path) 20, an introduction path (second path) 30, and a return path (third path) 40, and a control unit 60 that appropriately controls each part provided in the refrigerant circuit 10.

[0027] The circulation path 20 is configured in a ring shape by appropriately connecting the compressor 21, the external heat exchanger 22, the expansion mechanism 23, and the internal heat exchanger 24 with refrigerant lines 25, and refrigerant is sealed inside.

[0028] The compressor 21 is located in the machine room 9, as shown in Figure 2. The machine room 9 is inside the main cabinet 1, separated from the product storage area 3, and is located below the product storage area 3. The compressor 21 is driven in response to commands from the control unit 60, and draws in refrigerant through the suction port, compresses the drawn-in refrigerant to a high-temperature, high-pressure state (high-temperature, high-pressure refrigerant), and discharges it from the discharge port. A three-way valve 26 is provided in the refrigerant pipeline 25 connected to the discharge port of the compressor 21.

[0029] The three-way valve 26 has one inlet and two outlets (a first outlet and a second outlet), and is a switching valve that can be switched between a first discharge state, in which the inlet and the first outlet are connected, and a second discharge state, in which the inlet and the second outlet are connected, according to a command given by the control unit 60. The inlet of this three-way valve 26 is connected to a refrigerant line 25 that is connected to the discharge port of the compressor 21.

[0030] As shown in Figure 2, the external heat exchanger 22 is located in the machine room 9, similar to the compressor 21. This external heat exchanger 22 exchanges heat between the refrigerant passing through it and the surrounding air. An external blower fan is provided near the rear of the external heat exchanger 22. The refrigerant line 25 connected to the inlet side of the external heat exchanger 22 is connected to the first outlet of the three-way valve 26.

[0031] As shown in Figure 2, the expansion mechanism 23 is located in the machine room 9, similar to the compressor 21 and the external heat exchanger 22. This expansion mechanism 23 reduces the pressure of the refrigerant passing through it and causes adiabatic expansion, and is comprised of a first electronic expansion valve 23a, a second electronic expansion valve 23b, and a third electronic expansion valve 23c.

[0032] These first electronic expansion valve 23a, second electronic expansion valve 23b, and third electronic expansion valve 23c are installed in each of the three branches of the refrigerant pipeline 25 connected to the outlet side of the external heat exchanger 22.

[0033] Here, the first electronic expansion valve 23a, the second electronic expansion valve 23b, and the third electronic expansion valve 23c, which constitute the expansion mechanism 23, have their respective opening degrees adjusted according to commands given by the control unit 60.

[0034] Multiple internal heat exchangers 24 (three in the illustrated example) are provided and are located in the lower part of the interior of each product storage compartment 3, on the front side of the rear duct D (see Figure 2). The internal heat exchanger 24 located in the right compartment 3a (hereinafter also referred to as the right internal heat exchanger 24a) is connected to the refrigerant pipeline 25 downstream of the first electronic expansion valve 23a, the internal heat exchanger 24 located in the middle compartment 3b (hereinafter also referred to as the middle internal heat exchanger 24b) is connected to the refrigerant pipeline 25 downstream of the second electronic expansion valve 23b, and the internal heat exchanger 24 located inside the left compartment 3c (hereinafter also referred to as the left internal heat exchanger 24c) is connected to the refrigerant pipeline 25 downstream of the third electronic expansion valve 23c. In addition, a first check valve 27 is provided between the third electronic expansion valve 23c and the left internal heat exchanger 24c. This first check valve 27 allows the refrigerant that has passed through the third electronic expansion valve 23c to pass toward the left internal heat exchanger 24c, while restricting the passage of refrigerant from the left internal heat exchanger 24c toward the third electronic expansion valve 23c.

[0035] The refrigerant lines 25 connected to the outlet sides of the central heat exchanger 24b and the left heat exchanger 24c merge with each other, then merge with the refrigerant line 25 connected to the outlet side of the right heat exchanger 24a, and are then connected to the suction port of the compressor 21.

[0036] An outlet solenoid valve 28 is installed upstream of the point where the refrigerant pipeline 25 connected to the outlet side of the left internal heat exchanger 24c merges with the refrigerant pipeline 25 connected to the outlet side of the central internal heat exchanger 24b. The outlet solenoid valve 28 is an openable and closable valve body that opens to allow the passage of refrigerant when an open command is given from the control unit 60, and closes to restrict the passage of refrigerant when a close command is given.

[0037] The introduction route 30 has an introduction pipe 31, one end of which is connected to the second outlet of the three-way valve 26, and the other end which joins the refrigerant pipe 25 on the inlet side of the left internal heat exchanger 24c downstream of the first check valve 27. This introduction route 30 supplies the high-pressure refrigerant compressed by the compressor 21 to the left internal heat exchanger 24c when the introduction of refrigerant is permitted by the three-way valve 26. In other words, the left internal chamber 3c may be a chamber to be heated, and if it is a chamber to be heated, the left internal heat exchanger 24c is a heat exchanger inside a heated chamber.

[0038] The return path 40 has a return pipe 41 that branches off from the upstream side of the outlet solenoid valve 28 in the refrigerant pipe 25 connected to the outlet side of the left internal heat exchanger 24c, and joins the refrigerant pipe 25 that connects the three-way valve 26 and the external heat exchanger 22. A capillary tube 42 and a second check valve 43 are provided in this return pipe 41.

[0039] The capillary tube 42 causes the refrigerant passing through it to undergo adiabatic expansion. The second check valve 43 allows the refrigerant that has passed through the capillary tube 42 to pass towards the external heat exchanger 22, while restricting the passage of refrigerant from the external heat exchanger 22 towards the capillary tube 42.

[0040] Each of the product storage compartments 3 described above is equipped with an internal temperature detection unit 50 for detecting the internal temperature. The right internal temperature detection unit 50a detects the internal temperature of the right compartment 3a and sends the detection result to the control unit 60. The middle internal temperature detection unit 50b detects the internal temperature of the middle compartment 3b and sends the detection result to the control unit 60. The left internal temperature detection unit 50c detects the internal temperature of the left compartment 3c and sends the detection result to the control unit 60. Note that reference numeral 51 in Figure 3 indicates a heater. When the heater 51 is energized, it heats the internal air (internal atmosphere) of the left compartment 3c.

[0041] The control unit 60 comprehensively controls the operation of the refrigerant circuit device according to the program and data stored in the memory 61. The control unit 60 may be implemented by having a processing unit such as a CPU (Central Processing Unit) execute a program, i.e., by software; by hardware such as an IC (Integrated Circuit); or by a combination of software and hardware.

[0042] The following describes a case in which a refrigerant circuit device having the above configuration cools or heats the goods stored in the goods storage compartment 3.

[0043] First, as an example of cooling-only operation, we will explain the case of CCC operation (an operation that cools the internal air of all product storage compartments 3).

[0044] In this case, the control unit 60 adjusts the three-way valve 26 to the first discharge state and opens the outlet solenoid valve 28. The control unit 60 also adjusts the openings of the first electronic expansion valve 23a, the second electronic expansion valve 23b, and the third electronic expansion valve 23c, which constitute the expansion mechanism 23, to a predetermined size. As a result, the refrigerant compressed by the compressor 21 circulates as shown in Figure 4.

[0045] The refrigerant compressed by the compressor 21 is discharged from the discharge port, passes through the three-way valve 26 in the first discharge state, and reaches the external heat exchanger 22 via the refrigerant pipeline 25. The refrigerant that reaches the external heat exchanger 22 condenses as it passes through the external heat exchanger 22, releasing heat into the surrounding air (outside air). The refrigerant condensed in the external heat exchanger 22 undergoes adiabatic expansion by the expansion mechanism 23 (first electronic expansion valve 23a, second electronic expansion valve 23b, and third electronic expansion valve 23c) and reaches each internal heat exchanger 24, where it evaporates, absorbing heat from the internal air of the product storage compartment 3 and cooling the internal air. The cooled internal air is circulated inside by the drive of the internal ventilation fan F1 (see Figure 2) located near each internal heat exchanger 24, and the products stored in each product storage compartment 3 are cooled by the circulating internal air.

[0046] The refrigerants evaporated in each internal heat exchanger 24 are merged and then drawn into the compressor 21 through the suction port, where they are compressed and the circulation described above is repeated. At this point, the refrigerant that has passed through the left internal heat exchanger 24c may enter the return path 40, but a capillary tube 42 is provided in this return path 40, and due to the flow resistance of the capillary tube 42, the refrigerant that has passed through the left internal heat exchanger 24c does not reach the return path 40 but passes through the circulation path 20.

[0047] Next, as an example of a cooling and heating operation, we will explain the case of HCC operation (an operation in which the internal air of the left compartment 3c is heated and the internal air of the right compartment 3a and the middle compartment 3b is cooled). In this case, the explanation will assume that the internal atmosphere of the right compartment 3a and the middle compartment 3b is cooled to the same temperature range.

[0048] In this case, the control unit 60 adjusts the three-way valve 26 to the second discharge state and closes the outlet solenoid valve 28. The control unit 60 also adjusts the first electronic expansion valve 23a and the second electronic expansion valve 23b to have roughly the same opening degree, while closing the third electronic expansion valve 23c. As a result, the refrigerant compressed by the compressor 21 circulates as shown in Figure 5.

[0049] The refrigerant compressed by the compressor 21 is discharged from the discharge port and passes through the introduction pipe 31 via the three-way valve 26 in the second discharge state. The refrigerant that has passed through the introduction pipe 31 reaches the left internal heat exchanger 24c. As the refrigerant passes through the left internal heat exchanger 24c, it exchanges heat with the internal air of the left internal storage 3c and condenses, releasing heat into the internal air. This heats the internal air of the left internal storage 3c. The heated internal air is circulated inside the left internal storage 3c by the drive of the internal ventilation fan F1, and as a result, the products stored in the left internal storage 3c are heated by the circulating internal air.

[0050] The refrigerant condensed in the left internal heat exchanger 24c reaches the return pipe 41 and passes through the return pipe 41. The refrigerant passing through the return pipe 41 undergoes adiabatic expansion in the capillary tube 42, and then reaches the external heat exchanger 22, where it exchanges heat with the ambient air. The refrigerant that has passed through the external heat exchanger 22 undergoes adiabatic expansion in the first electronic expansion valve 23a and the second electronic expansion valve 23b.

[0051] The refrigerant, which has undergone adiabatic expansion in the first electronic expansion valve 23a, reaches the right internal heat exchanger 24a, where it evaporates, removing heat from the internal air of the right internal heat exchanger 24a and cooling the internal air. The cooled internal air is circulated inside the right internal heat exchanger 3a by the drive of the internal ventilation fan F1, thereby cooling the goods stored in the right internal heat exchanger 3a.

[0052] The refrigerant, adiabatically expanded by the second electronic expansion valve 23b, reaches the internal heat exchanger 24b, where it evaporates, removing heat from the internal air of the internal storage compartment 3b and cooling it. The cooled internal air is circulated inside the internal storage compartment 3b by the drive of the internal ventilation fan F1, thereby cooling the goods stored in the internal storage compartment 3b.

[0053] The refrigerants evaporated in the right internal heat exchanger 24a and the central internal heat exchanger 24b merge along the way and are drawn into the compressor 21 through the suction port. The refrigerants drawn into the compressor 21 are then compressed and the circulation described above is repeated.

[0054] In a refrigerant circuit device that performs such cooling and heating operations, the control unit 60 performs the following compressor on / off control.

[0055] Figure 6 is a time chart illustrating the compressor on / off control performed by the control unit 60. It should be noted that, in the following steps, the internal temperatures of the right chamber 3a and the left chamber 3c are adjusted to approximately the same level.

[0056] In this time chart, at time t0, the control unit 60 is set to stop the compressor 21. As a result, the temperature inside the left chamber 3c, which is a heating chamber, decreases, while the temperature inside the right chamber 3a and the middle chamber 3b, which are cooling chambers, increases.

[0057] If, at time t1, the internal temperatures of the right compartment 3a and the middle compartment 3b reach or exceed the cooling-on temperature at which cooling should normally begin, but the internal temperature of the left compartment 3c does not fall below the heating-on temperature at which heating should begin, the control unit 60 maintains the compressor 21 in a stopped state.

[0058] Then, at time t2, if the internal temperatures of the right compartment 3a and the middle compartment 3b are above the cooling-on temperature and below the cooling upper limit temperature (higher than the cooling-on temperature), and the internal temperature of the left compartment 3c is below the heating-on temperature, the control unit 60 drives the compressor 21. As a result, the internal temperature of the left compartment 3c increases, while the internal temperatures of the right compartment 3a and the middle compartment 3b decrease.

[0059] At time t3, if the internal temperatures of the right compartment 3a and the middle compartment 3b fall below the cooling-off temperature at which cooling is normally terminated, but the internal temperature of the left compartment 3c does not rise above the heating-off temperature at which heating is terminated, the control unit 60 maintains the operation of the compressor 21.

[0060] Then, at time t4, if the internal temperatures of the right compartment 3a and the middle compartment 3b are below the cooling off temperature and above the lower limit cooling temperature (which is lower than the cooling off temperature), and the internal temperature of the left compartment 3c is above the heating off temperature, the control unit 60 stops the compressor 21 from running. As a result, the internal temperature of the left compartment 3c decreases, while the internal temperatures of the right compartment 3a and the middle compartment 3b increase.

[0061] At time t5, if the internal temperature of the right compartment 3a and the middle compartment 3b rises above the cooling-on temperature, but the internal temperature of the left compartment 3c does not fall below the heating-on temperature, the control unit 60 maintains the compressor 21 in a stopped state.

[0062] Then, at time t6, if the internal temperatures of the right compartment 3a and the middle compartment 3b are within the cooling-on grace period temperature range, and the internal temperature of the left compartment 3c is below the heating-on temperature, the control unit 60 drives the compressor 21. This process is then repeated.

[0063] In other words, during cooling and heating operation, the control unit 60 performs compressor on / off control, where if the internal temperature of the cooling chambers (right chamber 3a and middle chamber 3b) is above a predetermined cooling on temperature but within the cooling on grace temperature range, it maintains the compressor 21's drive stopped until the internal temperature of the heating chamber (left chamber 3c) falls below the heating on temperature. On the other hand, if the internal temperature of the cooling chambers is below a predetermined cooling off temperature but within the cooling off grace temperature range, it maintains the compressor 21's drive until the internal temperature of the heating chamber rises above the heating off temperature.

[0064] Furthermore, in the above-described cooling and heating operation, if the internal temperature of the cooling chamber deviates from the cooling-on grace temperature range before the internal temperature of the heating chamber falls below the heating-on temperature, that is, if the internal temperature of the cooling chamber exceeds the upper cooling limit temperature, it is preferable for the control unit 60 to drive the compressor 21 by keeping the three-way valve 26 in the first discharge state, maintaining the third electronic expansion valve 23c in the closed state, and closing the outlet solenoid valve 28. This allows the internal air of the cooling chambers, the right chamber 3a and the middle chamber 3b, to be cooled.

[0065] On the other hand, if the internal temperature of the heating chamber falls below the heating-on temperature before the internal temperature of the cooling chamber rises above the cooling-on temperature, it is preferable for the control unit 60 to energize the heater 51. This allows the internal air of the left chamber 3c, which is the heating chamber, to be heated.

[0066] By the way, if the temperature inside the cooling chamber deviates from the cooling off grace temperature range before the temperature inside the heating chamber rises above the heating off temperature, that is, if the temperature inside the cooling chamber falls below the lower cooling limit temperature, it is preferable for the control unit 60 to stop the compressor 21 and energize the heater 51. This prevents the internal air of the cooling chamber from being excessively cooled and allows the internal air of the heating chamber to be heated.

[0067] Figure 7 is a flowchart showing the process of evaporation temperature control performed by the control unit 60 shown in Figure 2, separately from compressor on / off control, during cooling-heating operation (HCC operation). Note that in this evaporation temperature control, the internal temperatures of the right chamber 3a and the middle chamber 3b, which are cooling chambers, are assumed to be approximately the same.

[0068] In the evaporation temperature control, the control unit 60 determines whether or not the compressor 21 has started to drive (step S101). If the compressor 21 does not start to drive (step S101: No), the control unit 60 continues the process of step S101.

[0069] On the other hand, when the compressor 21 starts to drive (step S101: Yes), the control unit 60 inputs the temperature of the cooling chambers (right chamber 3a and middle chamber 3b), i.e., the cooling start temperature, through the internal temperature detection unit 50 (right internal temperature detection unit 50a and middle internal temperature detection unit 50b) (step S102).

[0070] Having received the cooling start temperature in this manner, the control unit 60 determines whether or not the compressor 21 has stopped running (step S103). If the compressor 21 does not stop running (step S103: No), the control unit 60 continues the process in step S103.

[0071] On the other hand, if the compressor 21 stops driving (step S103: Yes), the control unit 60 inputs the temperature of the cooling chambers (right chamber 3a and middle chamber 3b), i.e., the cooling completion temperature, through the internal temperature detection unit 50 (right internal temperature detection unit 50a and middle internal temperature detection unit 50b) (step S104).

[0072] Having received the cooling completion temperature in this manner, the control unit 60 calculates an intermediate temperature based on the temperature difference between the cooling start temperature and the cooling completion temperature (step S105), and compares the calculated intermediate temperature with the target temperature read from the memory 61 (steps S106, S107).

[0073] If the intermediate temperature is higher than the target temperature (Step S106: Yes), the control unit 60 reduces the opening of the expansion mechanism 23, which consists of the first electronic expansion valve 23a and the second electronic expansion valve 23b, by a predetermined amount, thereby reducing the flow rate in these expansion mechanisms 23 (first electronic expansion valve 23a and second electronic expansion valve 23b) by a predetermined amount (Step S108), and then returns to the previous step to terminate the current process.

[0074] According to this, the evaporation temperature of the refrigerant in the right internal heat exchanger 24a and the left internal heat exchanger 24c can be lowered, and the intermediate temperature can be brought closer to the target temperature.

[0075] If the intermediate temperature is lower than the target temperature (Step S106: No, Step S107: Yes), the control unit 60 increases the opening of the first electronic expansion valve 23a and the second electronic expansion valve 23b, which are the expansion mechanisms 23, by a predetermined amount, thereby increasing the flow rate in these expansion mechanisms 23 (first electronic expansion valve 23a and second electronic expansion valve 23b) by a predetermined amount (Step S109), and then returns to the previous step to end the current process.

[0076] According to this, the evaporation temperature of the refrigerant in the right internal heat exchanger 24a and the left internal heat exchanger 24c can be increased, bringing the intermediate temperature closer to the target temperature.

[0077] By the way, if the intermediate temperature matches the target temperature (step S106: No, step S107: No), the control unit 60 maintains the opening of the expansion mechanism 23 without performing the above-described process, and then returns to the previous step to terminate the current process.

[0078] As described above, according to the refrigerant circuit device of Embodiment 1 of the present invention, the control unit 60 maintains the deactivation of the compressor 21 until the internal temperature of the heating chamber falls below the heating on temperature if the internal temperature of the cooling chamber is above a predetermined cooling on temperature but within the cooling on grace temperature range, while maintaining the operation of the compressor 21 until the internal temperature of the heating chamber rises above the heating off temperature if the internal temperature of the cooling chamber is below a predetermined cooling off temperature but within the cooling off grace temperature range. This compressor on / off control allows for prioritizing the internal temperature of the heating chamber, where temperature control of stored goods is difficult, while reducing the number of times the compressor 21 is driven, thereby reducing power consumption.

[0079] Furthermore, according to the above-described refrigerant circuit device, the control unit 60 reduces the flow rate of refrigerant in the expansion mechanism 23 when the intermediate temperature of the temperature difference between the cooling start temperature and the cooling end temperature is higher than a preset target temperature, and increases the flow rate of refrigerant in the expansion mechanism 23 when the intermediate temperature is lower than the target temperature, thereby performing evaporation temperature control. This makes it possible to bring the intermediate temperature closer to the target temperature, thereby improving the cooling efficiency in the cooling and heating operation.

[0080] <Embodiment 2> Figure 8 is a conceptual diagram showing a refrigerant circuit device according to Embodiment 2 of the present invention. Note that the same components as those in the refrigerant circuit device of Embodiment 1 described above, as well as the parts of the vending machine to which this refrigerant circuit device is applied, are denoted by the same reference numerals, and their descriptions are omitted as appropriate.

[0081] The refrigerant circuit device illustrated here comprises a refrigerant circuit 10a having a circulation path (first path) 20, an introduction path (second path) 30, and a return path (third path) 40a, and a control unit 60a that appropriately controls each part provided in the refrigerant circuit 10a.

[0082] The return path 40a has a return pipe 41 that branches off from the upstream side of the outlet solenoid valve 28 in the refrigerant pipe 25 connected to the outlet side of the left internal heat exchanger 24c, and joins the refrigerant pipe 25 that connects the three-way valve 26 and the external heat exchanger 22. This return pipe 41 is equipped with a fourth electronic expansion valve (expansion valve) 42a and a second check valve 43. The fourth electronic expansion valve 42a adiabatically expands the refrigerant passing through it, and its opening degree is adjusted according to a command given by the control unit 60a.

[0083] The control unit 60a comprehensively controls the operation of the refrigerant circuit device according to the program and data stored in the memory 61a. The control unit 60a may be implemented by having a processing unit such as a CPU (Central Processing Unit) execute a program, i.e., by software; by hardware such as an IC (Integrated Circuit); or by a combination of software and hardware.

[0084] The following describes a case in which a refrigerant circuit device having the above configuration cools or heats the goods stored in the goods storage compartment 3.

[0085] First, as an example of cooling-only operation, we will explain the case of CCC operation (an operation that cools the internal air of all product storage compartments 3).

[0086] In this case, the control unit 60a adjusts the three-way valve 26 to the first discharge state and opens the outlet solenoid valve 28. The control unit 60a also adjusts the openings of the first electronic expansion valve 23a, the second electronic expansion valve 23b, and the third electronic expansion valve 23c, which constitute the expansion mechanism 23, to a predetermined size, and closes the fourth electronic expansion valve 42a. As a result, the refrigerant compressed by the compressor 21 circulates as shown in Figure 9.

[0087] The refrigerant compressed by the compressor 21 is discharged from the discharge port, passes through the three-way valve 26 in the first discharge state, and reaches the external heat exchanger 22 via the refrigerant pipeline 25. The refrigerant that reaches the external heat exchanger 22 condenses as it passes through the external heat exchanger 22, releasing heat into the surrounding air (outside air). The refrigerant condensed in the external heat exchanger 22 undergoes adiabatic expansion by the expansion mechanism 23 (first electronic expansion valve 23a, second electronic expansion valve 23b, and third electronic expansion valve 23c) and reaches each internal heat exchanger 24, where it evaporates, absorbing heat from the internal air of the product storage compartment 3 and cooling the internal air. The cooled internal air is circulated inside by the drive of the internal air blower fan F1 located near each internal heat exchanger 24, and the products stored in each product storage compartment 3 are cooled by the circulating internal air.

[0088] The refrigerants evaporated in each internal heat exchanger 24 are then combined and drawn into the compressor 21 through the suction port, where they are compressed and the circulation described above is repeated. At this point, there is a risk that the refrigerant that has passed through the left internal heat exchanger 24c may enter the return path 40a, but the fourth electronic expansion valve 42a of this return path 40a is closed, so the refrigerant that has passed through the left internal heat exchanger 24c does not reach the return path 40a and instead passes through the circulation path 20.

[0089] Next, as an example of a cooling and heating operation, we will explain the case of HCC operation (an operation in which the internal air of the left compartment 3c is heated and the internal air of the right compartment 3a and the middle compartment 3b is cooled). In this case, the explanation will assume that the internal atmosphere of the right compartment 3a and the middle compartment 3b is cooled to the same temperature range.

[0090] In this case, the control unit 60a adjusts the three-way valve 26 to the second discharge state and closes the outlet solenoid valve 28. The control unit 60a also adjusts the first electronic expansion valve 23a and the second electronic expansion valve 23b to have roughly the same opening degree, while closing the third electronic expansion valve 23c. Furthermore, the control unit 60a adjusts the opening degree of the fourth electronic expansion valve 42a to a predetermined size. As a result, the refrigerant compressed by the compressor 21 circulates as shown in Figure 10.

[0091] The refrigerant compressed by the compressor 21 is discharged from the discharge port and passes through the introduction pipe 31 via the three-way valve 26 in the second discharge state. The refrigerant that has passed through the introduction pipe 31 reaches the left internal heat exchanger 24c. As the refrigerant passes through the left internal heat exchanger 24c, it exchanges heat with the internal air of the left internal storage 3c and condenses, releasing heat into the internal air. This heats the internal air of the left internal storage 3c. The heated internal air is circulated inside the left internal storage 3c by the drive of the internal ventilation fan F1, and as a result, the products stored in the left internal storage 3c are heated by the circulating internal air.

[0092] The refrigerant condensed in the left internal heat exchanger 24c reaches the return pipe 41 and passes through it. The refrigerant passing through the return pipe 41 undergoes adiabatic expansion in the fourth electronic expansion valve 42a, and then reaches the external heat exchanger 22, where it exchanges heat with the ambient air. The refrigerant that has passed through the external heat exchanger 22 undergoes adiabatic expansion in the first electronic expansion valve 23a and the second electronic expansion valve 23b.

[0093] The refrigerant, which has undergone adiabatic expansion in the first electronic expansion valve 23a, reaches the right internal heat exchanger 24a, where it evaporates, removing heat from the internal air of the right internal heat exchanger 24a and cooling the internal air. The cooled internal air is circulated inside the right internal heat exchanger 3a by the drive of the internal ventilation fan F1, thereby cooling the goods stored in the right internal heat exchanger 3a.

[0094] The refrigerant, adiabatically expanded by the second electronic expansion valve 23b, reaches the internal heat exchanger 24b, where it evaporates, removing heat from the internal air of the internal storage compartment 3b and cooling it. The cooled internal air is circulated inside the internal storage compartment 3b by the drive of the internal ventilation fan F1, thereby cooling the goods stored in the internal storage compartment 3b.

[0095] The refrigerants evaporated in the right internal heat exchanger 24a and the central internal heat exchanger 24b merge along the way and are drawn into the compressor 21 through the suction port. The refrigerants drawn into the compressor 21 are then compressed and the circulation described above is repeated.

[0096] In a refrigerant circuit device that performs such cooling and heating operations, the control unit 60a performs compressor on / off control, similar to the refrigerant circuit device of Embodiment 1 described above.

[0097] In other words, during cooling and heating operation, the control unit 60a performs compressor on / off control, which maintains the operation of the compressor 21 until the temperature inside the heating chamber (left chamber 3c) falls below the heating on temperature if the internal temperature of the cooling chambers (right chamber 3a and middle chamber 3b) is above a predetermined cooling on temperature but within the cooling on grace temperature range. On the other hand, if the internal temperature of the cooling chambers is below a predetermined cooling off temperature but within the cooling off grace temperature range, the control unit 60a maintains the operation of the compressor 21 until the internal temperature of the heating chamber rises above the heating off temperature.

[0098] Furthermore, in the above-described cooling and heating operation, if the internal temperature of the cooling chamber deviates from the cooling-on grace temperature range before the internal temperature of the heating chamber falls below the heating-on temperature, that is, if the internal temperature of the cooling chamber exceeds the upper cooling limit temperature, it is preferable for the control unit 60a to drive the compressor 21 by keeping the three-way valve 26 in the first discharge state, maintaining the third electronic expansion valve 23c in the closed state, and closing the outlet solenoid valve 28. This allows the internal air of the cooling chambers, the right chamber 3a and the middle chamber 3b, to be cooled.

[0099] On the other hand, if the internal temperature of the heating chamber falls below the heating-on temperature before the internal temperature of the cooling chamber rises above the cooling-on temperature, it is preferable for the control unit 60a to energize the heater 51. This allows the internal air of the left chamber 3c, which is the heating chamber, to be heated.

[0100] By the way, if the temperature inside the cooling chamber deviates from the cooling off grace temperature range before the temperature inside the heating chamber rises above the heating off temperature, that is, if the temperature inside the cooling chamber falls below the lower cooling limit temperature, it is preferable for the control unit 60a to stop the compressor 21 and energize the heater 51. This prevents the internal air of the cooling chamber from being excessively cooled and allows the internal air of the heating chamber to be heated.

[0101] Figure 11 is a flowchart showing the processing details of the intermediate pressure control performed by the control unit 60a shown in Figure 8, separately from the compressor on / off control, during the cooling and heating operation (HCC operation). Note that in this intermediate pressure control, the internal temperatures of the right chamber 3a and the middle chamber 3b, which are cooling chambers, are assumed to be approximately the same.

[0102] In intermediate pressure control, the control unit 60a determines whether or not the compressor 21 has started to drive (step S201). If the compressor 21 does not start to drive (step S201: No), the control unit 60a continues the process of step S201.

[0103] On the other hand, when the compressor 21 starts to drive (step S201: Yes), the control unit 60a receives the temperature of the cooling chambers (right chamber 3a and middle chamber 3b), i.e., the cooling start temperature, through the internal temperature detection unit 50 (right internal temperature detection unit 50a and middle internal temperature detection unit 50b) (step S202).

[0104] Having received the cooling start temperature in this manner, the control unit 60a determines whether or not the compressor 21 has stopped running (step S203). If the compressor 21 does not stop running (step S203: No), the control unit 60a continues the process in step S203.

[0105] On the other hand, if the compressor 21 stops driving (step S203: Yes), the control unit 60a inputs the temperature of the cooling chambers (right chamber 3a and middle chamber 3b), i.e., the cooling completion temperature, through the internal temperature detection unit 50 (right internal temperature detection unit 50a and middle internal temperature detection unit 50b) (step S204).

[0106] Having received the cooling completion temperature in this manner, the control unit 60a calculates an intermediate temperature based on the temperature difference between the cooling start temperature and the cooling completion temperature (step S205), and compares the calculated intermediate temperature with the target temperature read from the memory 61a (steps S206, S207).

[0107] If the intermediate temperature is higher than the target temperature (step S206: Yes), the control unit 60a increases the opening degree of the fourth electronic expansion valve 42a by a predetermined amount, thereby increasing the flow rate in the fourth electronic expansion valve 42a by a predetermined amount (step S208), and then returns to the previous step to terminate the current process.

[0108] According to this, the amount of heat dissipated by the refrigerant in the external heat exchanger 22 can be increased, the cooling capacity of the right internal heat exchanger 24a and the left internal heat exchanger 24c can be increased, and the intermediate temperature can be brought closer to the target temperature.

[0109] If the intermediate temperature is lower than the target temperature (step S206: No, step S207: Yes), the control unit 60a reduces the flow rate in the fourth electronic expansion valve 42a by a predetermined amount by lowering the opening degree of the fourth electronic expansion valve 42a (step S209), and then returns to the previous step to terminate the current process.

[0110] According to this, the amount of heat dissipated by the refrigerant in the external heat exchanger 22 can be reduced, the cooling capacity of the right internal heat exchanger 24a and the left internal heat exchanger 24c can be reduced, and the intermediate temperature can be brought closer to the target temperature.

[0111] Incidentally, if the intermediate temperature matches the target temperature (step S206: No, step S207: No), the control unit 60a maintains the opening of the fourth electronic expansion valve 42a without performing the above-described process, and then returns to the previous step to terminate the current process.

[0112] As described above, according to the refrigerant circuit device of Embodiment 2 of the present invention, the control unit 60a performs compressor on / off control such as maintaining the operation of the compressor 21 until the temperature inside the heating chamber falls below the heating on temperature if the temperature inside the cooling chamber is above a predetermined cooling on temperature but within the cooling on grace temperature range, while maintaining the operation of the compressor 21 until the temperature inside the heating chamber rises above the heating off temperature if the temperature inside the cooling chamber is below a predetermined cooling off temperature but within the cooling off grace temperature range. This allows for a reduction in the number of times the compressor 21 is driven while prioritizing the temperature inside the heating chamber, where temperature control of stored goods is difficult, thereby reducing power consumption.

[0113] Furthermore, according to the above-described refrigerant circuit device, the control unit 60a increases the flow rate of refrigerant in the fourth electronic expansion valve 42a when the intermediate temperature of the temperature difference between the cooling start temperature and the cooling end temperature is higher than a preset target temperature, while reducing the flow rate of refrigerant in the fourth electronic expansion valve 42a when the intermediate temperature is lower than the target temperature. This intermediate pressure control brings the intermediate temperature closer to the target temperature, thereby improving the cooling efficiency in the cooling and heating operation.

[0114] Although preferred embodiments 1 and 2 of the present invention have been described above, the present invention is not limited thereto, and various modifications can be made.

[0115] In embodiments 1 and 2 described above, HCC operation was exemplified as an example of cooling and heating operation. However, in the present invention, HHC operation (an operation in which the internal air of the middle compartment 3b and the left compartment 3c is heated, and the internal air of the right compartment 3a is cooled) may also be used. In this case, it is preferable to heat the internal air of the middle compartment 3b with a heater (not shown).

[0116] In the above-described embodiment 1, not only compressor on / off control but also evaporation temperature control was explained, but in the present invention, only compressor on / off control may be performed.

[0117] In the above-described embodiment 2, not only compressor on / off control but also intermediate pressure control was explained, but in the present invention, only compressor on / off control may be performed.

[0118] In the embodiments 1 and 2 described above, a refrigerant circuit device applied to a vending machine was explained, but in the present invention, the refrigerant circuit device may be applied to equipment other than a vending machine. [Explanation of Symbols]

[0119] 1...Main cabinet, 3...Product storage compartment, 3a...Right compartment, 3b...Middle compartment, 3c...Left compartment, 10, 10a...Refrigerant circuit, 20...Circulation path (first path), 21...Compressor, 22...External heat exchanger, 23...Expansion mechanism, 23a...First electronic expansion valve, 23b...Second electronic expansion valve, 23c...Third electronic expansion valve, 24...Internal heat exchanger, 24a...Right internal heat exchanger, 24b...Middle internal heat exchanger, 24c...Left internal heat exchanger, 25...Refrigerant piping, 2 6... Three-way valve, 27... First check valve, 28... Solenoid valve for outlet, 30... Inlet path (second path), 31... Inlet pipeline, 40, 40a... Return path (third path), 41... Return pipeline, 42... Capillary tube, 42a... Fourth electronic expansion valve, 43... Second check valve, 50... Internal temperature detection unit, 50a... Right internal temperature detection unit, 50b... Middle internal temperature detection unit, 50c... Left internal temperature detection unit, 60, 60a... Control unit, 61, 61a... Memory.

Claims

1. A first path is formed by sequentially connecting an internal heat exchanger located inside the chamber, a compressor that sucks in and compresses the refrigerant that has passed through the internal heat exchanger, an external heat exchanger located outside the chamber, and an expansion mechanism that increases or decreases the flow rate of the refrigerant that has passed through the external heat exchanger to cause adiabatic expansion, via a refrigerant pipeline. When refrigerant is introduced by a switching valve provided in the refrigerant pipeline on the discharge side of the compressor, a second path supplies the refrigerant compressed by the compressor to the heating chamber heat exchanger located in the heating chamber to be heated, among the internal heat exchangers of the chamber. A third path supplies the refrigerant that has passed through the heat exchanger inside the heating chamber to the upstream side of the heat exchanger outside the chamber in the first path. A refrigerant circuit device having a refrigerant circuit, which circulates a refrigerant through the refrigerant circuit to heat the internal atmosphere of the heating chamber while cooling the internal atmosphere of any cooling chamber where an internal heat exchanger other than the internal heat exchanger of the heating chamber is installed, The control unit drives the compressor when the internal temperature of the heating chamber falls below a predetermined heating-on temperature, and stops the compressor when the internal temperature of the heating chamber rises above a predetermined heating-off temperature. The control unit performs compressor on / off control, which maintains the deactivation of the compressor until the heating chamber temperature falls below the heating chamber temperature if the internal temperature of the cooling chamber is above a predetermined cooling on temperature but within the cooling on grace temperature range, and maintains the operation of the compressor until the heating chamber temperature rises above the heating off temperature if the internal temperature of the cooling chamber is below a predetermined cooling off temperature but within the cooling off grace temperature range. Furthermore, the control unit is characterized by performing evaporation temperature control such that, if the intermediate temperature of the temperature difference between the cooling chamber temperature when the compressor is driven and the cooling chamber temperature when the compressor is stopped is higher than a preset target temperature, it reduces the flow rate of the refrigerant in the expansion mechanism, while increasing the flow rate of the refrigerant in the expansion mechanism if the intermediate temperature is lower than the target temperature.

2. A first path is formed by sequentially connecting an internal heat exchanger located inside the chamber, a compressor that sucks in and compresses the refrigerant that has passed through the internal heat exchanger, an external heat exchanger located outside the chamber, and an expansion mechanism that increases or decreases the flow rate of the refrigerant that has passed through the external heat exchanger to cause adiabatic expansion, via a refrigerant pipeline. When refrigerant is introduced by a switching valve provided in the refrigerant pipeline on the discharge side of the compressor, a second path supplies the refrigerant compressed by the compressor to the heating chamber heat exchanger located in the heating chamber to be heated, among the internal heat exchangers of the chamber. A third path supplies the refrigerant that has passed through the heat exchanger inside the heating chamber to the upstream side of the heat exchanger outside the chamber in the first path. A refrigerant circuit device having a refrigerant circuit, which circulates a refrigerant through the refrigerant circuit to heat the internal atmosphere of the heating chamber while cooling the internal atmosphere of any cooling chamber where an internal heat exchanger other than the internal heat exchanger of the heating chamber is installed, The control unit drives the compressor when the internal temperature of the heating chamber falls below a predetermined heating-on temperature, and stops the compressor when the internal temperature of the heating chamber rises above a predetermined heating-off temperature. The control unit performs compressor on / off control, which maintains the deactivation of the compressor until the heating chamber temperature falls below the heating chamber temperature if the internal temperature of the cooling chamber is above a predetermined cooling on temperature but within the cooling on grace temperature range, and maintains the operation of the compressor until the heating chamber temperature rises above the heating off temperature if the internal temperature of the cooling chamber is below a predetermined cooling off temperature but within the cooling off grace temperature range. The third path is equipped with an expansion valve that increases or decreases the flow rate of the refrigerant passing through it to cause the refrigerant to adiabatically expand. Furthermore, the control unit is characterized by performing intermediate pressure control such that, when the intermediate temperature of the temperature difference between the cooling chamber temperature when the compressor is driven and the cooling chamber temperature when the compressor is stopped is higher than a preset target temperature, the flow rate of refrigerant in the expansion valve is increased, while when the intermediate temperature is lower than the target temperature, the flow rate of refrigerant in the expansion valve is reduced.

3. The second path is provided in such a manner that it branches off from the refrigerant pipeline connecting the compressor and the external heat exchanger and merges with the refrigerant pipeline connecting the expansion mechanism and the internal heat exchanger of the heating chamber. The refrigerant circuit device according to claim 1 or 2, characterized in that the third path is provided in such a manner that it branches off from the refrigerant pipeline connecting the internal heat exchanger and the compressor and merges with the refrigerant pipeline connecting the compressor and the external heat exchanger.

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