JP2006242480A - Vapor compression cycle system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vapor compression cycle system capable of improving energy efficiency, by increasing a coefficient of performance of a refrigerating cycle and a heat pump cycle. <P>SOLUTION: A third heat exchanger 4 is arranged between a first expansion valve 6 and a second expansion valve 7. Thus, a refrigerant reduced in pressure by the first expansion valve 6 can be further cooled by the third heat exchanger 4, and the coefficient of performance COP can be improved when used for cooling operation of an air-conditioning facility and the refrigerating cycle of a refrigerator by increasing cooling capacity of a second heat exchanger 3. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a vapor compression cycle system used for hot water supply equipment, air conditioning equipment, and refrigeration equipment.

  Conventionally, as this type of vapor compression cycle system, a system in which carbon dioxide, which is a natural refrigerant, is used as a refrigerant instead of chlorofluorocarbon or alternative chlorofluorocarbon that causes ozone layer destruction and global warming has been proposed.

As a vapor compression cycle system using carbon dioxide, a refrigerant circuit in which refrigerant circulates sequentially through the compressor, the first heat exchanger, and the second heat exchanger, and the refrigerant flowing into the second heat exchanger are decompressed. There is known an expansion means that expands, and an internal heat exchanger that exchanges heat between the refrigerant flowing out of the first heat exchanger and the refrigerant sucked into the compressor. (For example, refer to Patent Document 1).
JP 2001-108308 A

  However, the conventional vapor compression cycle system has a problem that the coefficient of performance of the refrigeration cycle and the heat pump cycle is small as compared with refrigerants such as Freon, and the energy efficiency is poor.

  The present invention has been made in view of the above-mentioned problems, and its object is to increase the coefficient of performance of the refrigeration cycle and the heat pump cycle and to improve the energy efficiency of the vapor compression cycle system. Is to provide.

  In order to achieve the above object, the present invention depressurizes the refrigerant flowing in the second heat exchanger and the refrigerant circuit in which the refrigerant sequentially circulates through the compressor, the first heat exchanger, and the second heat exchanger. In a vapor compression cycle system comprising expansion means, and an internal heat exchanger for exchanging heat between the refrigerant flowing out of the first heat exchanger and the refrigerant sucked into the compressor, the expansion means includes the internal heat exchanger. The first expansion means for reducing the pressure of the refrigerant flowing out of the first expansion means, and the second expansion means for reducing the pressure of the refrigerant flowing through the first expansion means, and between the first expansion means and the second expansion means The 3rd heat exchanger which radiates the refrigerant | coolant which distribute | circulates is provided.

  Thereby, the refrigerant discharged from the compressor and flowing through the first heat exchanger is depressurized by the first expansion means and the second expansion means, and the refrigerant with the first expansion means and the second expansion means. Since the refrigerant circulating between them is cooled by the third heat exchanger, the degree of supercooling of the refrigerant decompressed by the first expansion means can be increased in the third heat exchanger.

  According to the present invention, since the degree of supercooling of the refrigerant decompressed by the first expansion means can be increased by the third heat exchanger, air conditioning can be achieved by increasing the cooling capacity of the second heat exchanger. The coefficient of performance COP can be improved when used in the cooling operation of equipment or in the refrigeration cycle of refrigeration equipment.

  1 and 2 show a first embodiment of the present invention. FIG. 1 is a circuit configuration diagram of a vapor compression cycle system, and FIG. 2 is a ph diagram showing the operation of the vapor compression cycle system.

  This vapor compression cycle system includes a compressor 1, a first heat exchanger 2, a second heat exchanger 3, a third heat exchanger 4, an internal heat exchanger 5, and a first expansion means. Expansion valve 6 and a second expansion valve 7 as second expansion means, which are connected by a refrigerant distribution pipe. That is, the refrigerant outlet of the compressor 1 is connected to the refrigerant inlet of the first heat exchanger 2, and the refrigerant outlet of the first heat exchanger 2 is connected to the high-pressure refrigerant inlet of the internal heat exchanger 5. It is connected. The refrigerant inlet of the third heat exchanger 4 is connected to the high-pressure refrigerant outlet of the internal heat exchanger 5, and the refrigerant flow of the second heat exchanger 3 is connected to the refrigerant outlet of the third heat exchanger 4. The entrance is connected. At this time, the first expansion valve 6 is connected between the high-pressure refrigerant outlet of the internal heat exchanger 5 and the refrigerant inlet of the third heat exchanger 4, and the refrigerant flow of the third heat exchanger 4 A second expansion valve 7 is connected between the outlet and the refrigerant inlet of the second heat exchanger 3. The refrigerant outlet of the second heat exchanger 3 is connected to the low-pressure refrigerant inlet of the internal heat exchanger 5, and the refrigerant inlet of the compressor 1 is connected to the low-pressure refrigerant outlet of the internal heat exchanger 5. Yes. Further, here, carbon dioxide whose high pressure side is in a supercritical state is used as the refrigerant.

  The compressor 1 is capable of compressing and discharging carbon dioxide as a refrigerant to a pressure equal to or higher than a critical point, and obtains a driving force from a driving source such as an engine or a motor.

  The first heat exchanger 2 is configured to exchange heat between the refrigerant discharged from the compressor 1 and the medium to be heated, so that the refrigerant dissipates heat and the medium to be heated absorbs heat. It has become.

  The second heat exchanger 3 is configured to exchange heat between the refrigerant that has flowed out of the third heat exchanger 4 and then depressurized by the second expansion valve 7 and the heat-absorbing medium. The refrigerant evaporates and absorbs heat by the exchanger 3, and the heat absorbing medium dissipates heat.

  The third heat exchanger 4 is configured to exchange heat between the refrigerant that has flowed out of the internal heat exchanger 5 and then decompressed by the first expansion valve 6 and the medium to be heated. Thus, the refrigerant dissipates heat and the heated medium absorbs heat.

  The internal heat exchanger 5 has a high-pressure refrigerant flow path and a low-pressure refrigerant flow path, and heat-exchanges the refrigerant that has flowed out of the first heat exchanger 2 and the refrigerant that has flowed out of the second heat exchanger 3. It has become.

  The 1st expansion valve 6 and the 2nd expansion valve 7 consist of a well-known manual on-off valve, and reduce | circulate and distribute | circulate a refrigerant | coolant according to the opening degree of a valve, respectively. The first expansion valve 6 and the second expansion valve 7 may be automatic open / close valves in addition to the manual open / close valves.

  In the vapor compression cycle system configured as described above, the refrigerant discharged from the compressor 1 flows through the high-pressure refrigerant flow passages of the first heat exchanger 2 and the internal heat exchanger 5 in order, It flows through the first expansion valve 6 to the heat exchanger 4. The refrigerant flowing out of the third heat exchanger 4 flows through the second heat exchanger 3 via the second expansion valve 7 and then flows through the low-pressure refrigerant flow path of the internal heat exchanger 5. It is sucked into the compressor 1.

  The operation of the refrigeration cycle at this time will be described with reference to the ph diagram of FIG.

  The refrigerant flowing out from the internal heat exchanger 5 is compressed to a supercritical state in the compressor 1 (AB). The refrigerant discharged from the compressor 1 is radiated and cooled by exchanging heat with the heated medium in the first heat exchanger 2 (B-C). The refrigerant flowing out of the first heat exchanger 2 is cooled by exchanging heat with the refrigerant flowing out of the second heat exchanger 3 in the internal heat exchanger 5 (CD). The refrigerant cooled in the internal heat exchanger 5 is depressurized by the first expansion valve 6 (DE). The refrigerant decompressed by the first expansion valve 6 is cooled by exchanging heat with the medium to be heated in the third heat exchanger 4 (EF). The refrigerant cooled in the third heat exchanger 4 is depressurized by the second expansion valve 7 (FG). The refrigerant decompressed by the second expansion valve 7 is made to absorb heat and evaporate by exchanging heat with the heat absorbing medium in the second heat exchanger 3 (GH). The degree of superheat is increased by exchanging heat of the refrigerant evaporated in the second heat exchanger 3 with the refrigerant flowing out of the first heat exchanger 2 in the internal heat exchanger 5 (HA).

  Thus, according to the vapor compression cycle system of the present embodiment, since the third heat exchanger 4 is provided between the first expansion valve 6 and the second expansion valve 7, the first expansion valve The refrigerant depressurized by 6 can be further cooled by the third heat exchanger 4, and by increasing the cooling capacity of the second heat exchanger 3, the cooling operation of the air conditioning equipment or the refrigeration cycle of the refrigeration equipment, etc. When used, the coefficient of performance COP can be improved.

  FIG. 3 shows a second embodiment of the present invention and is a circuit configuration diagram of a vapor compression cycle system. In addition, the same code | symbol is attached | subjected and shown to the component equivalent to the said 1st Embodiment.

  In the vapor compression cycle system according to the present embodiment, the second heat exchanger 3 and the third heat exchanger 4 are each constituted by a fin tube heat exchanger, and the second heat exchanger 3 and the third heat exchanger. The refrigerant flowing through 4 exchanges heat with air by the blower 8. Further, the third heat exchanger 4 is arranged on the downstream side of the second heat exchanger 3 with respect to the blowing direction of the blower 8.

  In the vapor compression cycle system configured as described above, the refrigerant discharged from the compressor 1 circulates in the same manner as in the first embodiment. At this time, the refrigerant flowing through the third heat exchanger 4 exchanges heat with air cooled by evaporation of the refrigerant flowing through the second heat exchanger 3.

  Thus, according to the evaporative compression cycle system of the present embodiment, the third heat exchanger 4 is arranged on the downstream side of the second heat exchanger 3 with respect to the blowing direction of the blower 8, so that the second heat Heat exchanged between the air cooled in the exchanger 3 and the refrigerant flowing through the third heat exchanger 4 can be performed, and the heat exchange capability of the third heat exchanger 4 can be improved.

  In the above embodiment, the third heat exchanger 4 is arranged on the downstream side of the second heat exchanger 3 with respect to the blowing direction of the blower 8, but as shown in FIG. A third heat exchanger 4 is arranged below the second heat exchanger 3, and the refrigerant flowing through the third heat exchanger 4 is exchanged with air for heat, and the outside of the second heat exchanger 3. The heat exchange capability of the third heat exchanger 4 can be improved by exchanging heat with the water condensed on the water.

  Moreover, in the said embodiment, although what showed the 3rd heat exchanger 4 arrange | positioned in the downstream of the 2nd heat exchanger 3 with respect to the ventilation direction of the air blower 8 was shown, when utilizing as a heat pump cycle. As shown in FIG. 5, the third heat exchanger 4 may be arranged on the upstream side of the second heat exchanger 3 with respect to the blowing direction of the blower 8. In this case, the refrigerant flowing through the second heat exchanger 3 can exchange heat with the air heated in the third heat exchanger 4. For example, the second refrigerant installed in an environment where the temperature in winter is low. Even when heat is absorbed by the heat exchanger 3, the heat exchange efficiency of the second heat exchanger 3 can be improved to obtain a high heating capacity, and frost formation of the second heat exchanger 3 can be prevented. Can do. When frost formation occurs in the second heat exchanger 3, the flow of the heated medium that exchanges heat with the refrigerant in the first heat exchanger 2 is stopped, and the blower 8 is stopped and the second heat exchanger 3 is stopped. The valve opening of the expansion valve 7 is fully opened. Thereby, the high-temperature refrigerant discharged from the compressor 1 circulates in the second heat exchanger 3 without being cooled in the first heat exchanger 2, and the frost adhered to the second heat exchanger 3. Is melted by the hot refrigerant.

  FIG. 6 shows a third embodiment of the present invention and is a circuit configuration diagram of a vapor compression cycle system. In addition, the same code | symbol is attached | subjected and shown to the component similar to the said 1st and 2nd embodiment.

  The vapor compression cycle system of the present embodiment detects the temperature of the refrigerant 9 flowing out from the second heat exchanger 3 and the heater 9 as a heating means for heating the refrigerant flowing out from the second heat exchanger 3. A temperature detector 10 and a controller 11 that controls the output of the heater 9 based on the temperature detected by the temperature detector 10 are provided.

  In the vapor compression cycle system configured as described above, the refrigerant discharged from the compressor 1 circulates in the same manner as in the first embodiment. In addition, when the temperature of the heat absorbing medium that exchanges heat with the refrigerant flowing through the second heat exchanger 3 is low, it is difficult for the refrigerant to absorb the necessary amount of heat in the second heat exchanger 3. . Therefore, when the temperature detected by the temperature detector 10 is lower than the predetermined set temperature, the refrigerant is heated by the heater 9, and when the detected temperature is higher than the set temperature, the energization of the heater 9 is stopped or the output is reduced. Let

  Thus, according to the vapor compression cycle system of the present embodiment, since the heater 9 for heating the refrigerant flowing out from the second heat exchanger 3 is provided, the refrigerant flowing out from the second heat exchanger 3 The refrigerant can be surely absorbed by the refrigerant, and for example, when used as a heat pump cycle in an environment where the outside air temperature is low in winter, it is possible to prevent a decrease in heating capacity.

  In addition, since the output of the heater 9 is controlled based on the temperature detected by the temperature detector 10 that detects the temperature of the refrigerant flowing out of the second heat exchanger 3, the necessary amount of heat can be reduced by the heater 9 without excess or deficiency. The refrigerant can absorb heat and energy consumption can be reduced.

  In addition, in the said embodiment, although what provided the heater 9 and the temperature detector 10 in the refrigerant | coolant outflow side of the 2nd heat exchanger 3 was shown, as shown in FIG. Even if the heater 9 and the temperature detector 10 are provided on the refrigerant inflow side, the same effect as in the above embodiment can be obtained. Further, as shown in FIG. 8, when air is used as the heat absorbing medium that exchanges heat with the refrigerant flowing through the second heat exchanger 3, the heater 9 is provided on the upstream side of the second heat exchanger 3. In addition, even if the temperature detector 10 is provided on the downstream side of the second heat exchanger 3, the same effect as in the above embodiment can be obtained.

  FIG. 9 shows a fourth embodiment of the present invention and is a circuit configuration diagram of a vapor compression cycle system. In addition, the same code | symbol is attached | subjected and shown to the component similar to the said 1st thru | or 3rd embodiment.

  In the vapor compression cycle system of the present embodiment, the second expansion valve 7 is an electronic expansion valve that can be opened and closed by a stepping motor, receives refrigerant flowing out from the second heat exchanger 3, and flows out only gas refrigerant. An accumulator 12 that can be used, a temperature detector 13-1 that detects the temperature of the refrigerant on the refrigerant inlet side of the first heat exchanger 2, and a second temperature based on the detected temperature of the temperature detector 13-1. The control part 11 for controlling the valve opening degree of the expansion valve 7 is provided. The control unit 11 is constituted by a microcomputer, and a program for controlling the valve opening degree of the second expansion valve 7 is stored in the memory.

  In the vapor compression cycle system configured as described above, the refrigerant discharged from the compressor 1 circulates in the same manner as in the first embodiment.

  Here, in order to set the temperature of the refrigerant flowing into the first heat exchanger 2 to a predetermined set temperature, the control unit 11 performs the following operation. When the detected temperature of the temperature detector 13-1 is lower than the set temperature, the valve opening degree of the second expansion valve 7 is increased. As a result, the amount of refrigerant flowing through the refrigerant inlet side of the compressor 1 increases, the discharge pressure of the compressor 1 increases, and the temperature of the refrigerant flowing into the first heat exchanger 2 increases. Further, when the temperature detected by the temperature detector 13-1 is higher than the set temperature, the opening degree of the second expansion valve 7 is decreased. As a result, the amount of refrigerant flowing through the refrigerant inlet side of the compressor 1 decreases, the discharge pressure of the compressor 1 decreases, and the temperature of the refrigerant flowing into the first heat exchanger 2 decreases.

  Thus, according to the vapor compression cycle system of the present embodiment, the temperature of the refrigerant flowing into the first heat exchanger 2 is detected by the temperature detector 13-1, and the detected temperature of the temperature detector 13-1 is obtained. Since the valve opening degree of the second expansion valve 7 is controlled based on the above, the temperature of the refrigerant flowing into the first heat exchanger 2 can always be kept at a predetermined set temperature, which is used as a heat pump cycle. In this case, the heating capacity can be improved and the energy efficiency can be improved.

  FIG. 10 shows a fifth embodiment of the present invention and is a circuit configuration diagram of a vapor compression cycle system. In addition, the same code | symbol is attached | subjected and shown to the component similar to the said 1st thru | or 4th embodiment.

  The vapor compression cycle system of the present embodiment includes a pressure detector 14 that detects the pressure on the refrigerant outflow side of the internal heat exchanger 5 using the second expansion valve 7 as an electronic expansion valve, and the control unit 11 includes a pressure detector. The valve opening degree of the second expansion valve 7 is controlled based on the detected pressure 14.

  In the vapor compression cycle system configured as described above, the refrigerant discharged from the compressor 1 circulates in the same manner as in the first embodiment.

  Here, in order to set the pressure on the refrigerant outflow side of the internal heat exchanger 5 to a predetermined set pressure, the control unit 11 performs the following operation. When the detected pressure of the pressure detector 14 is lower than the set pressure, the valve opening degree of the second expansion valve 7 is decreased. Thereby, the flow resistance between the refrigerant | coolant discharge side of the compressor 1 and the 1st expansion valve 7 increases, and a pressure becomes high. Further, when the detected pressure of the pressure detector 14 is higher than the set pressure, the opening degree of the second expansion valve 7 is increased. Thereby, the flow resistance between the refrigerant | coolant discharge side of the compressor 1 and the 1st expansion valve 7 reduces, and a pressure becomes low.

  Thus, according to the vapor compression cycle system of the present embodiment, the pressure on the refrigerant outflow side of the internal heat exchanger 5 is detected by the pressure detector 14, and the second expansion is performed based on the detected pressure of the pressure detector 14. Since the opening degree of the valve 7 is controlled, the pressure in the first heat exchanger 2 can be maintained at a predetermined set pressure, and when used as a heat pump cycle, the heating capacity is improved and the energy efficiency is improved. Improvements can be made.

  In the above-described embodiment, the pressure detector 14 detects the pressure on the refrigerant outflow side of the internal heat exchanger 5. However, for example, the discharge side of the compressor 1 or the first heat exchanger 2 is used. Even if the pressure detector 14 is provided on the refrigerant outflow side, the pressure on the high pressure side of the vapor compression cycle system can be detected.

  FIG. 11 shows a sixth embodiment of the present invention and is a circuit configuration diagram of a vapor compression cycle system. In addition, the same code | symbol is attached | subjected and shown to the component similar to the said 1st thru | or 5th embodiment.

  In the vapor compression cycle system of the present embodiment, the second expansion valve 7 is an electronic expansion valve, the first temperature detector 15 that detects the temperature of the refrigerant flowing into the second heat exchanger 3, and the second A second temperature detector 16 that detects the temperature of the refrigerant flowing out of the heat exchanger 3, and the controller 11 detects the detected temperature of the first temperature detector 15 and the detected temperature of the second temperature detector 16. Is calculated, and the valve opening degree of the second expansion valve 7 is controlled based on the temperature difference.

  In the vapor compression cycle system configured as described above, the refrigerant discharged from the compressor 1 circulates in the same manner as in the first embodiment.

  Here, in order to control the temperature difference between the refrigerant flowing into the second heat exchanger 3 and the refrigerant flowing out of the second heat exchanger 3 to a predetermined set temperature difference, the control unit 11 operates as follows. I do. When the temperature difference between the temperature detected by the first temperature detector 15 and the temperature detected by the second temperature detector 16 is calculated and the temperature difference is smaller than the set temperature difference, the valve of the second expansion valve 7 is calculated. Reduce the opening. As a result, the amount of refrigerant flowing into the second heat exchanger 3 is reduced, and the pressure in the second heat exchanger 3 is reduced, and the degree of superheat of the refrigerant flowing out of the second heat exchanger 3 is increased. Thus, the temperature difference between the detected temperature of the first temperature detector 15 and the detected temperature of the second temperature detector 16 increases. Further, when the temperature difference between the detected temperature of the first temperature detector 15 and the detected temperature of the second temperature detector 16 is larger than the set temperature difference, the opening degree of the second expansion valve 7 is increased. . As a result, the amount of refrigerant flowing into the second heat exchanger 3 increases, and the pressure in the second heat exchanger 3 increases to reduce the degree of superheat of the refrigerant flowing out of the second heat exchanger 3. Thus, the temperature difference between the detected temperature of the first temperature detector 15 and the detected temperature of the second temperature detector 16 becomes small.

  Thus, according to the vapor compression cycle system of the present embodiment, based on the temperature difference between the temperature of the refrigerant flowing into the second heat exchanger 3 and the temperature of the refrigerant flowing out of the second heat exchanger 3. Since the valve opening degree of the second expansion valve 7 is controlled, the degree of superheat of the refrigerant flowing through the second heat exchanger 3 can be set to an appropriate state, and the efficiency can be improved. .

  FIG. 12 shows a seventh embodiment of the present invention and is a circuit configuration diagram of a vapor compression cycle system. In addition, the same code | symbol is attached | subjected and shown to the component similar to the said 1st thru | or 6th embodiment.

  In the vapor compression cycle system of the present embodiment, the first expansion valve 6 and the second expansion valve 7 are electronic expansion valves, respectively, and the first temperature for detecting the temperature of the refrigerant flowing into the second heat exchanger 3 is detected. A detector 15, a second temperature detector 16 that detects the temperature of the refrigerant that flows out of the second heat exchanger 3, and a third temperature that detects the temperature of the refrigerant that flows into the first heat exchanger 2. And a detector 13-2. The control unit 11 controls the valve opening degree of the second expansion valve 7 based on the temperature difference between the detected temperature of the first temperature detector 15 and the detected temperature of the second temperature detector 16, and the third The valve opening degree of the first expansion valve 6 is controlled based on the detected temperature of the temperature detector 13-2.

  In the vapor compression cycle system configured as described above, the refrigerant discharged from the compressor 1 circulates in the same manner as in the first embodiment.

  Here, in order to make the temperature difference between the temperature of the refrigerant flowing into the second heat exchanger 3 and the temperature of the refrigerant flowing out of the second heat exchanger 3 a predetermined set temperature difference, the control unit 11 The same operation as in the sixth embodiment is performed. When the temperature difference between the temperature detected by the first temperature detector 15 and the temperature detected by the second temperature detector 16 is calculated and the temperature difference is smaller than the set temperature difference, the valve of the second expansion valve 7 is calculated. Reduce the opening. Thereby, the temperature difference between the detected temperature of the first temperature detector 15 and the detected temperature of the second temperature detector 16 increases. When the temperature difference between the detected temperature of the first temperature detector 15 and the detected temperature of the second temperature detector 16 is larger than the set temperature difference, the valve opening of the second expansion valve 7 is increased. To do. Thereby, the temperature difference between the detected temperature of the first temperature detector 15 and the detected temperature of the second temperature detector 16 is reduced.

  Further, in order to set the temperature of the refrigerant flowing into the first heat exchanger 2 to a predetermined set temperature, the control unit 11 performs the following operation. When the detected temperature of the third temperature detector 13-2 is lower than the set temperature, the opening degree of the first expansion valve 6 is decreased. As a result, the amount of refrigerant flowing into the third heat exchanger 4 via the first expansion valve 6 decreases, and the pressure between the discharge side of the compressor 1 and the first expansion valve 6 increases. The amount of refrigerant increases and the temperature of the refrigerant flowing into the first heat exchanger 2 rises. Further, when the detected temperature of the third temperature detector 13-2 is higher than the set temperature, the valve opening degree of the first expansion valve 6 is increased. As a result, the amount of refrigerant flowing into the third heat exchanger 4 via the first expansion valve 6 increases, and the pressure and refrigerant amount between the discharge side of the compressor 1 and the first expansion valve 6 are increased. The temperature of the refrigerant that decreases and flows into the first heat exchanger 2 decreases.

  Thus, according to the vapor compression cycle system of the present embodiment, based on the temperature difference between the temperature of the refrigerant flowing into the second heat exchanger 3 and the temperature of the refrigerant flowing out of the second heat exchanger 3. Since the opening degree of the second expansion valve 7 is controlled and the opening degree of the first expansion valve 6 is controlled based on the temperature of the refrigerant flowing into the first heat exchanger 2, The temperature of the refrigerant flowing into the first heat exchanger 2 can be maintained at a predetermined set temperature, and the temperature of the refrigerant flowing into the second heat exchanger 3 and the refrigerant flowing out from the second heat exchanger 3 The temperature difference from the above temperature can be maintained at a predetermined set temperature difference of an appropriate degree of superheat, so that the cooling capacity and the heating capacity can be improved and the energy efficiency can be improved.

  FIG. 13 shows an eighth embodiment of the present invention and is a circuit configuration diagram of a vapor compression cycle system. In addition, the same code | symbol is attached | subjected and shown to the component similar to the said 1st thru | or 7th embodiment.

  In the vapor compression cycle system of the present embodiment, the first expansion valve 6 and the second expansion valve 7 are electronic expansion valves, respectively, and the first temperature for detecting the temperature of the refrigerant flowing into the second heat exchanger 3 is detected. A detector 15, a second temperature detector 16 for detecting the temperature of the refrigerant flowing out of the second heat exchanger 3, and a pressure detector 14 for detecting the pressure on the refrigerant outflow side of the internal heat exchanger 5. I have. The control unit 11 controls the valve opening degree of the second expansion valve 7 based on the temperature difference between the detected temperature of the first temperature detector 15 and the detected temperature of the second temperature detector 16 and detects the pressure. The valve opening degree of the first expansion valve 6 is controlled based on the detected pressure of the container 14.

  In the vapor compression cycle system configured as described above, the refrigerant discharged from the compressor 1 circulates in the same manner as in the first embodiment.

  Here, in order to make the temperature difference between the temperature of the refrigerant flowing into the second heat exchanger 3 and the temperature of the refrigerant flowing out of the second heat exchanger 3 a predetermined set temperature difference, the control unit 11 The same operation as in the sixth embodiment is performed. When the temperature difference between the temperature detected by the first temperature detector 15 and the temperature detected by the second temperature detector 16 is calculated and the temperature difference is smaller than the set temperature difference, the valve of the second expansion valve 7 is calculated. Reduce the opening. Thereby, the temperature difference between the detected temperature of the first temperature detector 15 and the detected temperature of the second temperature detector 16 increases. When the temperature difference between the detected temperature of the first temperature detector 15 and the detected temperature of the second temperature detector 16 is larger than the set temperature difference, the valve opening of the second expansion valve 7 is increased. To do. Thereby, the temperature difference between the detected temperature of the first temperature detector 15 and the detected temperature of the second temperature detector 16 is reduced.

  Further, in order to control the pressure on the refrigerant outflow side of the internal heat exchanger 5 to a predetermined set pressure, the control unit 11 performs the following operation. When the detected pressure of the pressure detector 14 is lower than the set pressure, the valve opening degree of the first expansion valve 6 is decreased. Thereby, the flow resistance between the discharge side of the compressor 1 and the 3rd heat exchanger 4 increases, and a pressure becomes high. Further, when the detected pressure of the pressure detector 14 is higher than the set pressure, the opening degree of the first expansion valve 6 is increased. Thereby, the flow resistance between the discharge side of the compressor 1 and the 3rd heat exchanger 4 reduces, and a pressure falls.

  Thus, according to the vapor compression cycle system of the present embodiment, based on the temperature difference between the temperature of the refrigerant flowing into the second heat exchanger 3 and the temperature of the refrigerant flowing out of the second heat exchanger 3. While controlling the valve opening degree of the second expansion valve 7 and controlling the valve opening degree of the first expansion valve 6 based on the pressure on the refrigerant outflow side of the internal heat exchanger 5, The pressure in the heat exchanger 2 can be maintained at a predetermined set pressure, and the temperature between the temperature of the refrigerant flowing into the second heat exchanger 3 and the temperature of the refrigerant flowing out of the second heat exchanger 3 The difference can be maintained at a predetermined set temperature difference with an appropriate degree of superheat, so that the cooling capacity and the heating capacity can be improved and the energy efficiency can be improved.

  FIG. 14 shows a ninth embodiment of the present invention and is a circuit configuration diagram of a vapor compression cycle system. The same components as those in the first to eighth embodiments are denoted by the same reference numerals.

  In the vapor compression cycle system of the present embodiment, the second expansion valve 7 is an electronic expansion valve, the first temperature detector 15 that detects the temperature of the refrigerant flowing into the second heat exchanger 3, and the second A second temperature detector 16 for detecting the temperature of the refrigerant flowing out from the heat exchanger 3 and a pressure detector 14 for detecting the pressure on the refrigerant outflow side of the internal heat exchanger 5 are provided. Further, the compressor 1 used here is driven by a DC motor or the like whose rotation speed can be changed by inverter control, and can increase or decrease the circulation amount of the refrigerant. The control unit 11 controls the valve opening degree of the second expansion valve 7 based on the detected temperature of the first temperature detector 15 and the detected temperature of the second temperature detector 16 and detects the pressure detector 14. The rotation speed of the compressor 1 is controlled based on the pressure.

  In the vapor compression cycle system configured as described above, the refrigerant discharged from the compressor 1 circulates in the same manner as in the first embodiment.

  Here, in order to make the temperature difference between the temperature of the refrigerant flowing into the second heat exchanger 3 and the temperature of the refrigerant flowing out of the second heat exchanger 3 a predetermined set temperature difference, the control unit 11 The same operation as in the sixth embodiment is performed. When the temperature difference between the temperature detected by the first temperature detector 15 and the temperature detected by the second temperature detector 16 is calculated and the temperature difference is smaller than the set temperature difference, the valve of the second expansion valve 7 is calculated. Reduce the opening. Thereby, the temperature difference between the detected temperature of the first temperature detector 15 and the detected temperature of the second temperature detector 16 increases. When the temperature difference between the detected temperature of the first temperature detector 15 and the detected temperature of the second temperature detector 16 is larger than the set temperature difference, the valve opening of the second expansion valve 7 is increased. To do. Thereby, the temperature difference between the detected temperature of the first temperature detector 15 and the detected temperature of the second temperature detector 16 is reduced.

  Further, in order to control the pressure on the refrigerant outflow side of the internal heat exchanger 5 to a predetermined set pressure, the control unit 11 performs the following operation. When the detected pressure of the pressure detector 14 is lower than the set pressure, the rotational speed of the compressor 1 is increased. As a result, the amount of refrigerant discharged from the compressor 1 increases, the amount of refrigerant between the discharge side of the compressor 1 and the first expansion valve 6 increases, and the pressure increases. Further, when the detected pressure of the pressure detector 14 is higher than the set pressure, the rotational speed of the compressor 1 is decreased. Thereby, the amount of refrigerant discharged from the compressor 1 decreases, the amount of refrigerant between the discharge side of the compressor 1 and the first expansion valve 6 decreases, and the pressure decreases.

  Thus, according to the vapor compression cycle system of the present embodiment, based on the temperature difference between the temperature of the refrigerant flowing into the second heat exchanger 3 and the temperature of the refrigerant flowing out of the second heat exchanger 3. While controlling the valve opening degree of the second expansion valve 7 and controlling the valve opening degree of the first expansion valve 6 based on the pressure on the refrigerant outflow side of the internal heat exchanger 5, The pressure in the heat exchanger 2 can be maintained at a predetermined set pressure, and the temperature difference between the temperature of the refrigerant flowing into the second heat exchanger 3 and the temperature of the refrigerant flowing out of the second heat exchanger 3 Can be maintained at a predetermined set temperature with an appropriate degree of superheat, so that the cooling capacity and the heating capacity can be improved and the energy efficiency can be improved.

  15 and 16 show a tenth embodiment of the present invention. FIG. 15 is a circuit configuration diagram of a vapor compression cycle system during cooling operation, and FIG. 16 is a circuit configuration diagram of the vapor compression cycle system during heating operation. It is. In addition, the same code | symbol is attached | subjected and shown to the component similar to the said 1st thru | or 9th embodiment.

  The vapor compression cycle system of this embodiment is applied to an air conditioner capable of switching between cooling and heating. The first heat exchanger 2 is an outdoor unit, and the second heat exchanger 3 is an indoor unit. It is what. This vapor compression cycle system uses electronic expansion valves as the first expansion valve 6 and the second expansion valve 7, respectively, and the refrigerant flowing through the third heat exchanger 4 side of the second heat exchanger 3. A first temperature detector 15 for detecting the temperature, a second temperature detector 16 for detecting the temperature of the refrigerant flowing through the internal heat exchanger 5 side of the second heat exchanger 3, and a cooling refrigerant flow path As a switching means capable of switching between the cooling refrigerant flow path and the heating refrigerant flow path as the heating refrigerant flow path, and the internal heat exchanger 5 side of the third heat exchanger 4. A third temperature detector 18 for detecting the temperature of the refrigerant, a fourth temperature detector 19 for detecting the temperature of the refrigerant flowing through the second heat exchanger 3 side of the third heat exchanger 4, and A fifth temperature detector 13-3 for detecting the temperature of the refrigerant flowing through the compressor 1 side of the first heat exchanger 2; A sixth temperature detector 20 for detecting the temperature of the refrigerant flowing through the internal heat exchanger 5 side of the heat exchanger 2 and a seventh temperature detector 21 for detecting the temperature of indoor air as a heat exchange medium. I have.

  In the vapor compression cycle system configured as described above, when the four-way valve 17 switches to the cooling refrigerant flow path, the refrigerant discharged from the compressor 1 is, as shown in FIG. 15, the first heat exchanger 2. Then, after sequentially flowing through the internal heat exchanger 5, it flows through the third heat exchanger 4 through the first expansion valve 6. The refrigerant flowing out of the third heat exchanger 4 flows through the second heat exchanger 3 through the second expansion valve 7, then flows through the internal heat exchanger 5 and is sucked into the compressor 1. Is done.

  At this time, the control unit 11 controls the valve opening degree of the first expansion valve 6 based on the temperature detected by the fifth temperature detector 13-3, and the detected temperature of the first temperature detector 15 and the first temperature. The valve opening degree of the second expansion valve 7 is controlled based on the temperature difference from the temperature detected by the second temperature detector 16. As a result, by setting the temperature of the refrigerant flowing into the first heat exchanger 2 to an optimum predetermined set temperature, it is possible to efficiently dissipate the refrigerant in the first heat exchanger 2. Further, by setting the temperature difference between the temperature of the refrigerant flowing into the second heat exchanger 3 and the temperature of the refrigerant flowing out of the second heat exchanger 3 as a predetermined set temperature difference of the optimum superheat degree, The cooling capacity of the second heat exchanger 3 can be improved.

  Further, when the four-way valve 17 is switched to the heating refrigerant flow path, the refrigerant discharged from the compressor 1 passes through the internal heat exchanger 5 and the second heat exchanger 3 sequentially as shown in FIG. The third heat exchanger 4 is circulated through the second expansion valve 7. The refrigerant flowing out from the third heat exchanger 4 flows through the internal heat exchanger 5 through the first expansion valve 6, then flows through the first heat exchanger 2 and is sucked into the compressor 1. Is done.

  At this time, the control unit 11 controls the valve opening degree of the second control valve 7 based on the temperature detected by the second temperature detector 16, and the detected temperature of the seventh temperature detector 21 is set to a predetermined value. When the temperature is lower than the temperature, the valve opening degree of the first expansion valve 6 is controlled based on the temperature difference between the temperature detected by the fifth temperature detector 13-3 and the temperature detected by the sixth temperature detector 20. When the detected temperature of the seventh temperature detector 21 is equal to or higher than a predetermined set temperature, the temperature difference between the detected temperature of the third temperature detector 18 and the detected temperature of the fourth temperature detector 19 is determined. The valve opening degree of the first expansion valve 6 is controlled. Thereby, the heating capacity of the second heat exchanger 3 can be improved by setting the temperature of the refrigerant flowing into the second heat exchanger 3 to an optimum set temperature. In addition, the temperature difference between the temperature of the refrigerant flowing into the first heat exchanger 2 and the temperature of the refrigerant flowing out of the first heat exchanger 2 is optimized until the temperature of the indoor air reaches a predetermined set temperature. Since the first heat exchanger 2 can surely absorb heat by setting a predetermined set temperature difference of the degree of superheat, it is possible to obtain a stable heating capability in the second heat exchanger 3. . Furthermore, after the indoor air temperature reaches a predetermined set temperature, the temperature difference between the temperature of the refrigerant flowing into the third heat exchanger 4 and the temperature of the refrigerant flowing out of the third heat exchanger is optimized. By setting the predetermined temperature difference, it is possible to obtain the optimum degree of refrigerant subcooling in the third heat exchanger 4, and thus it is possible to perform a heating operation with high energy efficiency.

  As described above, according to the vapor compression cycle system of the present embodiment, the refrigerant discharged from the compressor 1 is sequentially passed through the first heat exchanger 2 and the internal heat exchanger 5 and then the first expansion valve 6. Is supplied to the third heat exchanger 4 through the second expansion valve 7, and is supplied to the second heat exchanger 3 through the second expansion valve 7, and then is supplied to the internal heat exchanger 5 and the compressor 1. The flow path and the refrigerant discharged from the compressor 1 are sequentially circulated through the internal heat exchanger 5 and the second heat exchanger 3, and then are circulated through the second expansion valve 7 to the third heat exchanger 4. The four-way valve 17 is used to switch between the first heat exchanger 2 and the heating refrigerant flow path that sequentially flows to the compressor 1 after the internal heat exchanger 5 has been circulated through the first expansion valve 6. Therefore, it is possible to switch between the refrigeration cycle and heat pump cycle, and the air conditioning with carbon dioxide refrigerant. The heating and cooling apparatus or the like can be used in devices that require.

  Further, during the cooling operation, the opening degree of the first expansion valve 6 is controlled based on the temperature of the refrigerant flowing into the first heat exchanger 2 and the temperature of the refrigerant flowing into the second heat exchanger 3 is controlled. And the temperature of the refrigerant flowing out of the second heat exchanger 3 is controlled based on the temperature difference between the second expansion valve 7 and the refrigerant flowing into the second heat exchanger 3 during the heating operation. The valve opening degree of the second control valve 7 is controlled based on the temperature of the refrigerant, and when the temperature of the indoor air is lower than a predetermined set temperature, the temperature of the refrigerant flowing into the first heat exchanger 2 is When the valve opening degree of the first expansion valve 6 is controlled based on the temperature difference from the temperature of the refrigerant flowing out of the first heat exchanger 2, the temperature of the indoor air is equal to or higher than a predetermined set temperature. 1 based on the temperature difference between the temperature of the refrigerant flowing into the third heat exchanger 4 and the temperature of the refrigerant flowing out of the third heat exchanger 4. Since the valve opening degree of the expansion valve 6 is controlled, the valve opening degree of the first expansion valve 6 and the second expansion valve 7 which are optimum for the cooling operation and the heating operation can be set, respectively, and the cooling capacity In addition, the heating capacity and energy efficiency can be improved.

  17 and 18 show an eleventh embodiment of the present invention. FIG. 17 is a circuit configuration diagram of a vapor compression cycle system during cooling operation, and FIG. 18 is a circuit configuration diagram of the vapor compression cycle system during heating operation. It is. The same components as those in the first to tenth embodiments are denoted by the same reference numerals.

The vapor compression cycle system of the present embodiment is applied to an air conditioner capable of switching between cooling operation and heating operation, as in the tenth embodiment.
This vapor compression cycle system uses electronic expansion valves as the first expansion valve 6 and the second expansion valve 7, respectively, and the refrigerant flowing through the third heat exchanger 4 side of the second heat exchanger 3. A first temperature detector 15 for detecting the temperature, a second temperature detector 16 for detecting the temperature of the refrigerant flowing through the internal heat exchanger 5 side of the second heat exchanger 3, and a cooling refrigerant flow path As a switching means capable of switching between the cooling refrigerant flow path and the heating refrigerant flow path as the heating refrigerant flow path, and the internal heat exchanger 5 side of the third heat exchanger 4. A third temperature detector 18 for detecting the temperature of the refrigerant, a fourth temperature detector 19 for detecting the temperature of the refrigerant flowing through the second heat exchanger 3 side of the third heat exchanger 4, and A fifth temperature detector 13-3 for detecting the temperature of the refrigerant flowing through the compressor 1 side of the first heat exchanger 2; A sixth temperature detector 20 for detecting the temperature of the refrigerant flowing through the internal heat exchanger 5 side of the heat exchanger 2, and a seventh temperature detector 21 for detecting the temperature of indoor air as a heat exchange medium; And a pressure detector 22 for detecting the discharge pressure of the compressor 1.

  In the vapor compression cycle system configured as described above, when the four-way valve 17 switches to the cooling refrigerant flow path, the refrigerant discharged from the compressor 1 is converted into the first heat exchanger 2 as shown in FIG. Then, after sequentially flowing through the internal heat exchanger 5, it flows through the third heat exchanger 4 through the first expansion valve 6. The refrigerant flowing out of the third heat exchanger 4 flows through the second heat exchanger 3 through the second expansion valve 7, then flows through the internal heat exchanger 5 and is sucked into the compressor 1. Is done.

  At this time, the control unit 11 controls the valve opening degree of the first expansion valve 6 based on the detected temperature of the pressure detector 22, and the detected temperature of the first temperature detector 15 and the second temperature detector. The valve opening degree of the second expansion valve 7 is controlled based on the temperature difference with the detected temperature of 16. Thus, the refrigerant can be efficiently radiated in the first heat exchanger 2 by setting the discharge pressure of the compressor 1 to an optimum predetermined set pressure. Further, by setting the temperature difference between the temperature of the refrigerant flowing into the second heat exchanger 3 and the temperature of the refrigerant flowing out of the second heat exchanger 3 as a predetermined set temperature difference of the optimum superheat degree, The cooling capacity of the second heat exchanger 3 can be improved.

  When the four-way valve 17 is switched to the heating refrigerant flow path, the refrigerant discharged from the compressor 1 flows through the internal heat exchanger 5 and the second heat exchanger 3 sequentially as shown in FIG. The third heat exchanger 4 is circulated through the second expansion valve 7. The refrigerant flowing out from the third heat exchanger 4 flows through the internal heat exchanger 5 through the first expansion valve 6, then flows through the first heat exchanger 2 and is sucked into the compressor 1. Is done.

  At this time, the control unit 11 controls the valve opening degree of the second expansion valve 7 based on the detected pressure of the pressure detector 22, and the detected temperature of the seventh temperature detector 21 is lower than a predetermined set temperature. When the temperature is low, the valve opening degree of the first control valve 6 is controlled based on the temperature difference between the detected temperature of the fifth temperature detector 13-3 and the detected temperature of the sixth temperature detector 20, 7 is detected based on the temperature difference between the temperature detected by the third temperature detector 18 and the temperature detected by the fourth temperature detector 19. The valve opening degree of the expansion valve 6 is controlled. Thereby, the heating capacity of the second heat exchanger 3 can be improved by setting the discharge pressure of the compressor 1 to an optimal predetermined set pressure. In addition, the temperature difference between the temperature of the refrigerant flowing into the first heat exchanger 2 and the temperature of the refrigerant flowing out of the first heat exchanger 2 is optimized until the temperature of the indoor air reaches a predetermined set temperature. Since the first heat exchanger 2 can surely absorb heat by setting a predetermined set temperature difference of the degree of superheat, it is possible to obtain a stable heating capability in the second heat exchanger 3. . Furthermore, after the indoor air temperature reaches a predetermined set temperature, the temperature difference between the temperature of the refrigerant flowing into the third heat exchanger 4 and the temperature of the refrigerant flowing out of the third heat exchanger is optimized. By setting the predetermined temperature difference, it is possible to obtain the optimum degree of refrigerant subcooling in the third heat exchanger 4, and thus it is possible to perform a heating operation with high energy efficiency.

  Thus, according to the vapor compression cycle system of the present embodiment, during the cooling operation, the valve opening degree of the first expansion valve 6 is controlled based on the discharge pressure of the compressor 1, and the second heat exchanger 3 is controlled based on the temperature difference between the temperature of the refrigerant flowing into the refrigerant 3 and the temperature of the refrigerant flowing out of the second heat exchanger 3, and during the heating operation, While controlling the valve opening degree of the second expansion valve 7 based on the discharge pressure and when the temperature of the indoor air is lower than a predetermined set temperature, the temperature of the refrigerant flowing into the first heat exchanger 2 When the valve opening degree of the first expansion valve 6 is controlled based on the temperature difference from the temperature of the refrigerant flowing out of the first heat exchanger 2, the temperature of the indoor air is equal to or higher than a predetermined set temperature. The temperature of the refrigerant flowing into the third heat exchanger 4 and the temperature of the refrigerant flowing out of the third heat exchanger 4 Since the valve opening degree of the first expansion valve 6 is controlled based on the above, the valve opening degrees of the first expansion valve 6 and the second expansion valve 7 that are optimum for the cooling operation and the heating operation, respectively, are set. The cooling capacity and the heating capacity can be improved and the energy efficiency can be improved.

The circuit block diagram of the vapor | steam compression cycle system which shows the 1st Embodiment of this invention Ph diagram showing operation of vapor compression cycle system The circuit block diagram of the vapor | steam compression cycle system which shows the 2nd Embodiment of this invention Side view of second heat exchanger and third heat exchanger showing other examples Circuit configuration diagram of vapor compression cycle system showing other examples The circuit block diagram of the vapor compression cycle system which shows the 3rd Embodiment of this invention Circuit configuration diagram of vapor compression cycle system showing other examples Circuit configuration diagram of vapor compression cycle system showing other examples The circuit block diagram of the vapor compression cycle system which shows the 4th Embodiment of this invention The circuit block diagram of the vapor | steam compression cycle system which shows the 5th Embodiment of this invention The circuit block diagram of the vapor | steam compression cycle system which shows the 6th Embodiment of this invention Circuit configuration diagram of a vapor compression cycle system showing a seventh embodiment of the present invention The circuit block diagram of the vapor compression cycle system which shows the 8th Embodiment of this invention The circuit block diagram of the vapor | steam compression cycle system which shows the 9th Embodiment of this invention The circuit block diagram of the vapor | steam compression cycle system at the time of the cooling operation which shows the 10th Embodiment of this invention Circuit configuration diagram of vapor compression cycle system during heating operation The circuit block diagram of the vapor | steam compression cycle system at the time of air_conditionaing | cooling operation which shows the 11th Embodiment of this invention Circuit configuration diagram of vapor compression cycle system during heating operation

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Compressor, 2 ... 1st heat exchanger, 3 ... 2nd heat exchanger, 4 ... 3rd heat exchanger, 5 ... Internal heat exchanger, 6 ... 1st expansion valve, 7 ... 1st 2 expansion valve, 8 ... blower, 9 ... heater, 10 ... temperature detector, 11 ... control unit, 13-1 ... temperature detector, 13-2 ... third temperature detector, 13-3 ... fifth Temperature detector, 14 ... Pressure detector, 15 ... First temperature detector, 16 ... Second temperature detector, 17 ... Four-way valve, 18 ... Third temperature detector, 19 ... Fourth temperature detector 20 ... sixth temperature detector, 21 ... seventh temperature detector, 22 ... pressure detector.

Claims (15)

From the compressor, the first heat exchanger, the refrigerant circuit in which the refrigerant sequentially circulates through the second heat exchanger, the expansion means for decompressing the refrigerant flowing into the second heat exchanger, and the first heat exchanger In a vapor compression cycle system comprising an internal heat exchanger for exchanging heat between refrigerant flowing out and refrigerant sucked into the compressor,
The expansion means is composed of first expansion means for reducing the pressure of the refrigerant flowing out from the internal heat exchanger, and second expansion means for reducing the pressure of the refrigerant flowing through the first expansion means,
A vapor compression cycle system comprising a third heat exchanger that dissipates heat of the refrigerant flowing between the first expansion means and the second expansion means. A blower that circulates air that exchanges heat with a refrigerant that circulates through the second heat exchanger and the third heat exchanger;
The vapor compression cycle system according to claim 1, wherein the third heat exchanger is disposed on the leeward side of the second heat exchanger. A blower that circulates air that exchanges heat with a refrigerant that circulates through the second heat exchanger and the third heat exchanger;
The vapor compression cycle system according to claim 1, further comprising heat exchange means for exchanging moisture in the air condensed by the second heat exchanger with a refrigerant flowing through the third heat exchanger. A blower that circulates air that exchanges heat with a refrigerant that circulates through the second heat exchanger and the third heat exchanger;
The vapor compression cycle system according to claim 1, wherein the third heat exchanger is disposed on the windward side of the second heat exchanger. The vapor compression cycle system according to claim 1, further comprising a heating unit that heats the refrigerant flowing through the second heat exchanger side. A temperature detector for detecting the temperature of the refrigerant heated by the heating means;
The vapor compression cycle system according to claim 5, further comprising a heating control unit that controls a heating amount of the heating unit based on a temperature detected by the temperature detector. A temperature detector for detecting the temperature of the refrigerant flowing into the first heat exchanger;
The flow rate control means for controlling the flow rate of the refrigerant flowing into the second heat exchanger by the second expansion means based on the temperature detected by the temperature detector. 4. The vapor compression cycle system according to 4. A pressure detector for detecting the pressure of the refrigerant before being decompressed by the first expansion means or the pressure of the refrigerant after being decompressed by the first expansion valve;
The flow rate control means for controlling the flow rate of the refrigerant flowing into the second heat exchanger by the second expansion means based on the detected pressure of the pressure detector. 4. The vapor compression cycle system according to 4. A first temperature detector for detecting a temperature of the refrigerant flowing into the second heat exchanger;
A second temperature detector for detecting the temperature of the refrigerant flowing out of the second heat exchanger;
And a flow rate control means for controlling the flow rate of the refrigerant flowing into the second heat exchanger by the second expansion means based on the detected temperature of the first temperature detector and the detected temperature of the second temperature detector. The vapor compression cycle system according to claim 1, 2, 3 or 4. A third temperature detector for detecting the temperature of the refrigerant flowing into the first heat exchanger;
The steam according to claim 9, further comprising flow rate control means for controlling the flow rate of the refrigerant flowing into the third heat exchanger by the first expansion means based on the temperature detected by the third temperature detector. Compression cycle system. A pressure detector for detecting the pressure of the refrigerant discharged from the compressor;
The vapor compression cycle system according to claim 9, further comprising a flow rate control means for controlling a flow rate of the refrigerant flowing into the third heat exchanger by the first expansion means based on a detected pressure of the pressure detector. . While using a variable capacity compressor as the compressor,
A pressure detector for detecting the pressure of the refrigerant discharged from the compressor;
The vapor compression cycle system according to claim 9, further comprising a flow rate control unit that controls a capacity of the compressor based on a detected pressure of the pressure detector. The refrigerant discharged from the compressor is sequentially circulated through the first heat exchanger and the internal heat exchanger, and then is circulated through the first expansion means to the third heat exchanger, and the second expansion means is provided. A refrigerant flow path for cooling that is circulated through the internal heat exchanger and the compressor after being circulated through the second heat exchanger via
The refrigerant discharged from the compressor is sequentially circulated to the internal heat exchanger and the second heat exchanger, and then is circulated to the third heat exchanger via the second expansion means, and then via the first expansion means. The first heat exchanger after the internal heat exchanger is circulated, and the heating refrigerant flow path that is sequentially circulated to the compressor,
The vapor compression cycle system according to claim 1, 2, 3 or 4, further comprising switching means capable of switching between the cooling refrigerant flow path and the heating refrigerant flow path. A first temperature detector for detecting a temperature of the refrigerant flowing through the third heat exchanger side of the second heat exchanger;
A second temperature detector for detecting the temperature of the refrigerant flowing through the internal heat exchanger side of the second heat exchanger;
A third temperature detector for detecting the temperature of the refrigerant flowing through the internal heat exchanger side of the third heat exchanger;
A fourth temperature detector for detecting the temperature of the refrigerant flowing through the second heat exchanger side of the third heat exchanger;
A fifth temperature detector for detecting the temperature of the refrigerant flowing through the compressor side of the first heat exchanger;
A sixth temperature detector for detecting the temperature of the refrigerant flowing through the internal heat exchanger side of the first heat exchanger;
A seventh temperature detector for detecting the temperature of the heat exchange medium that exchanges heat with the refrigerant in the second heat exchanger;
In the cooling refrigerant flow path, the flow rate of the refrigerant flowing into the third heat exchanger is controlled by the first expansion means based on the detected temperature of the fifth temperature detector, and the detection of the first temperature detector is performed. The flow rate of the refrigerant flowing into the second heat exchanger is controlled by the second expansion means based on the temperature and the temperature detected by the second temperature detector, and the second temperature detector When the flow rate of the refrigerant flowing into the third heat exchanger is controlled by the second expansion means based on the detected temperature, and the detected temperature of the seventh temperature detector is lower than a predetermined set temperature, The flow rate of the refrigerant flowing into the first heat exchanger is controlled by the first expansion means based on the detected temperature of the temperature detector of 5 and the detected temperature of the sixth temperature detector, and the seventh temperature detector If the detected temperature is equal to or higher than the preset temperature, the third temperature And a flow rate control means for controlling the flow rate of the refrigerant flowing into the first heat exchanger by the first expansion means based on the detected temperature of the heat exchanger and the detected temperature of the fourth temperature detector. The vapor compression cycle system according to claim 13. A first temperature detector for detecting a temperature of the refrigerant flowing through the third heat exchanger side of the second heat exchanger;
A second temperature detector for detecting the temperature of the refrigerant flowing through the internal heat exchanger side of the second heat exchanger;
A third temperature detector for detecting the temperature of the refrigerant flowing through the internal heat exchanger side of the third heat exchanger;
A fourth temperature detector for detecting the temperature of the refrigerant flowing through the second heat exchanger side of the third heat exchanger;
A fifth temperature detector for detecting the temperature of the refrigerant flowing through the compressor side of the first heat exchanger;
A sixth temperature detector for detecting the temperature of the refrigerant flowing through the internal heat exchanger side of the first heat exchanger;
A seventh temperature detector for detecting the temperature of the heat exchange medium that exchanges heat with the refrigerant in the second heat exchanger;
A pressure detector for detecting the pressure of the refrigerant discharged from the compressor;
In the cooling refrigerant flow path, the flow rate of the refrigerant flowing into the third heat exchanger is controlled by the first expansion means based on the detected pressure of the pressure detector, and the detected temperature and the first temperature of the first temperature detector are controlled. The flow rate of the refrigerant flowing into the second heat exchanger is controlled by the second expansion means based on the temperature detected by the temperature detector of the second temperature detector, and the first flow rate is determined based on the detected pressure of the pressure detector in the heating refrigerant flow path. When the flow rate of the refrigerant flowing into the third heat exchanger is controlled by the second expansion means and the detected temperature of the seventh temperature detector is lower than a predetermined set temperature, the fifth temperature detector The flow rate of the refrigerant flowing into the first heat exchanger is controlled by the first expansion means based on the detected temperature and the detected temperature of the sixth temperature detector, and the detected temperature of the seventh temperature detector is set to a predetermined value. If it is higher than the temperature, the temperature detected by the third temperature detector And flow rate control means for controlling the flow rate of the refrigerant flowing into the first heat exchanger by the first expansion means based on the temperature detected by the fourth temperature detector. Vapor compression cycle system.

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