JP2019034690A - Air conditioner - Google Patents

Abstract

To provide an air conditioner equipped with cooling and heating functions that can improve cooling and heating performance.SOLUTION: An air conditioner 1 includes a refrigerant circuit 12 for cooling having a first heat exchanger 38, a refrigerant circuit 13 for heating that shares the first heat exchanger 38 with the refrigerant circuit 12 for cooling, a plurality of flow channel switching parts for switching the flow channel of the refrigerant, and a control part 15 for controlling the flow channel switching parts. The refrigerant circuit 13 for heating includes a compressor 30, a second heat exchanger 31, a receiver 34, a cooling part 35 to which the refrigerant from the receiver 34 is supplied, a first expansion valve 36 for decompressing the refrigerant from the cooling part 35, and the first heat exchanger 38 to which the refrigerant from the first expansion valve 36 is supplied. By controlling the flow channel switching parts, the control part 15 supplies the refrigerant from the first heat exchanger 38 to the receiver 34 without causing it to pass through the cooling part 35 at the time of cooling, and supplies the refrigerant from the receiver 34 to the first heat exchanger 38 through the cooling part 35 at the time of heating.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an air conditioner.

  In an air conditioning system for vehicles such as EV (Electric Vehicle), HEV (Plug-in Hybrid Vehicle), and PHEV (Plug-in Hybrid Electric Vehicle), heating operation using combustion exhaust heat such as engine cooling water can be performed. Can not. For this reason, a heat pump type air conditioning harmony system using an electric compressor is considered.

  For example, Patent Document 1 proposes a heat pump air conditioning system shown in FIG. Specifically, the outdoor heat exchanger 100 is shared during heating and cooling, and the switching valve provided in the refrigerant circuit is controlled, and during the cooling, the outdoor heat exchanger 100 is used as a condenser, and during the heating The use of the outdoor heat exchanger 100 as an evaporator is described.

Japanese Patent Laying-Open No. 2015-620

  As disclosed in Patent Document 1, when the refrigerant circuit is configured so that the outdoor heat exchanger 100 has both functions of an evaporator and a condenser, both functions of air conditioning are realized with a simple circuit configuration. can do. However, since the proper refrigerant amount range required for the outdoor heat exchanger 100 to exhibit sufficient heat exchange capability differs between cooling and heating, there arises a problem that sufficient capability cannot be exhibited.

Specifically, as shown in FIGS. 13 and 14, when the outdoor heat exchanger 100 is used as a condenser, the proper refrigerant amount range of the outdoor heat exchanger 100 is that the outdoor heat exchanger 100 is used as an evaporator. In addition to being less than the appropriate refrigerant amount range of the outdoor heat exchanger 100 in this case, both ranges usually do not overlap. For this reason, conventionally, the amount of refrigerant sealed in the system is determined based on the heating standard. As a result, the amount of refrigerant became insufficient during cooling, and sufficient heat exchange capability could not be exhibited.

  This invention is made | formed in view of such a situation, Comprising: It aims at providing the air conditioning apparatus which can improve a cooling / heating capability in an air conditioning apparatus provided with an air conditioning function.

  According to a first aspect of the present invention, there is provided a cooling refrigerant circuit having a first heat exchanger and a receiver, a heating refrigerant circuit sharing the first heat exchanger and the receiver with the cooling refrigerant circuit, and a refrigerant flow A plurality of flow path switching means provided in the cooling refrigerant circuit and the heating refrigerant circuit for switching the path, and a control means for controlling the flow path switching means, the heating refrigerant circuit, A compressor that compresses the refrigerant supplied from the first heat exchanger, a second heat exchange means that is supplied with the refrigerant compressed by the compressor, and a refrigerant that is condensed by the second heat exchange means is supplied. The receiver to which the refrigerant is supplied, the cooling means for cooling the refrigerant, the first expansion valve for decompressing the refrigerant from the cooling means, and the refrigerant from the first expansion valve are supplied. Said first heat exchanger being The control means controls the flow path switching means to supply the refrigerant from the first heat exchanger to the receiver without passing through the cooling means during cooling, and from the receiver during heating. It is an air conditioning apparatus which supplies the said refrigerant | coolant to the said 1st heat exchanger via the said cooling means.

  According to such a configuration, the cooling refrigerant circuit and the heating refrigerant circuit share the first heat exchanger, and supply the refrigerant cooled by the cooling means to the first heat exchanger only during heating. Therefore, it is possible to increase the optimum amount of refrigerant when the first heat exchanger is used as an evaporator during heating. That is, by excessively cooling the refrigerant supplied to the first heat exchanger operating as an evaporator, it is possible to increase the range of the optimum refrigerant amount when the first heat exchanger is used as an evaporator during heating. . For this reason, when the first heat exchanger is used as a condenser, the appropriate refrigerant amount range of the first heat exchanger, and when the first heat exchanger is used as an evaporator, the appropriate refrigerant amount of the first heat exchanger It is possible to obtain a refrigerant amount range that overlaps with the range, and by designing the refrigerant amount to be charged in the air conditioner within the overlapped refrigerant amount range, the first heat exchanger can be either a condenser or an evaporator. Even when it is used as, the heat exchange ability can be sufficiently exhibited. Further, by supplying the refrigerant that has been excessively cooled by the cooling means to the first heat exchanger that functions as an evaporator, the degree of thirst can be reduced and the flow rate of the refrigerant can be reduced. For this reason, it is possible to keep a large amount of the liquid-phase refrigerant flowing through the first heat exchanger, and as a result, pressure loss and temperature gradient at the inlet and outlet of the first heat exchanger are reduced. Therefore, partial frost formation in the first heat exchanger can be suppressed.

  In the air conditioning apparatus, the heating refrigerant circuit includes a first pipe that supplies the refrigerant from the receiver to the first expansion valve via the cooling unit, and the flow path provided in the first pipe. A first open / close valve serving as a switching unit, wherein the cooling refrigerant circuit includes a second expansion valve to which the refrigerant from the receiver is supplied through a second pipe, and the flow path provided in the second pipe. And a second opening / closing valve as a switching means, wherein the control means closes the first opening / closing valve during cooling and closes the second opening / closing valve during heating.

  According to such a configuration, since the first on-off valve and the second on-off valve are provided in each of the first pipe and the second pipe, the first expansion valve and the second expansion valve are switched when the flow path is switched. It becomes possible to interrupt the refrigerant upstream of the refrigerant flow.

  In the air conditioning apparatus, the heating refrigerant circuit includes a first pipe that supplies the refrigerant from the receiver to the first expansion valve via the cooling unit, and the flow path provided in the first pipe. An on-off valve as a switching means, wherein the cooling refrigerant circuit includes a second expansion valve to which the refrigerant from the receiver is supplied through a second pipe, and the second expansion valve serves as the flow path switching means. The control means may close the open / close valve during cooling and close the second expansion valve during heating.

  According to such a configuration, since the on-off valve is provided in the first pipe, it is possible to shut off the refrigerant on the upstream side of the refrigerant flow of the first expansion valve when the flow path is switched. In addition, since the second expansion valve has a configuration including the flow path switching function, it is possible to reduce the number of parts and the maintenance load as compared with the case where the flow path switching means is arranged in the second pipe. .

  In the above air conditioner, the heating refrigerant circuit includes a first pipe that supplies the refrigerant from the receiver to the first expansion valve via the cooling means, and the cooling refrigerant circuit is supplied from the receiver. The refrigerant is supplied through a second pipe with a second expansion valve and an opening / closing valve as the flow path switching means provided in the second pipe, and the first expansion valve serves as the flow path switching means. The control means may close the first expansion valve during cooling and close the open / close valve during heating.

  According to such a configuration, since the on-off valve is provided in the second pipe, the refrigerant can be blocked on the upstream side of the refrigerant flow of the second expansion valve when the flow path is switched. In addition, since the first expansion valve has a configuration in which the flow path switching function is provided, it is possible to reduce the number of parts and the maintenance load as compared with the case where the flow path switching means is arranged in the first pipe. .

  In the air conditioning apparatus, the cooling refrigerant circuit includes a second expansion valve to which the refrigerant from the receiver is supplied, and each of the first expansion valve and the second expansion valve serves as the flow path switching unit. The control means may close the first expansion valve during cooling and close the second expansion valve during heating.

  According to such a configuration, since the first expansion valve and the second expansion valve have a flow channel switching function, it is not necessary to provide a new flow channel switching means for switching the refrigerant flow channel. For this reason, it is possible to reduce the number of parts and the maintenance load.

  In the above air conditioner, the appropriate refrigerant amount range of the first heat exchanger when the first heat exchanger is used as a condenser, and the first when the first heat exchanger is used as an evaporator. It is good also as having filled the refrigerant | coolant amount in the refrigerant | coolant amount range with which the appropriate refrigerant | coolant amount range of the heat exchanger overlapped.

  According to such a configuration, in both cases where the first heat exchanger is used as a condenser and when the first heat exchanger is used as an evaporator, the first heat exchanger has an appropriate amount of refrigerant. The first heat exchanger can exhibit sufficient heat exchange capability.

  The said air conditioning apparatus WHEREIN: The said cooling means is good also as arrange | positioning in the upstream of the air flow of a said 1st heat exchanger.

  According to such a configuration, a part of the air flowing into the first heat exchanger is heated by the cooling means, and the average temperature of the inflowing air of the first heat exchanger becomes high, so the first heat exchange When the vessel is used as an evaporator, the ability to evaporate the refrigerant can be improved. Moreover, instead of improving the evaporation capability of the first heat exchanger, the refrigerant amount can be reduced while maintaining the capability, and the first heat exchanger can be downsized. In particular, it is possible to cope with a case where there are restrictions on the location and volume of the air conditioner, such as when the air conditioner is mounted on a car.

  In the above air conditioner, the cooling means is located upstream of the air flow of the first heat exchanger, and is disposed at a position where the saturation temperature of the refrigerant circulating in the first heat exchanger is the lowest. Also good.

  According to such a configuration, in the first heat exchanger, the position where the saturation temperature of the circulating refrigerant is the lowest is most likely to form frost. Therefore, by supplying the air heated by the cooling means to the position, Generation | occurrence | production of frost can be suppressed.

  In the above air conditioner, the cooling means may be arranged on the upstream side of the air flow of the first heat exchanger and at a position where the liquid phase refrigerant circulating in the first heat exchanger is the largest. .

  According to such a configuration, in the first heat exchanger, since the position where the circulating liquid phase refrigerant is the most easily frosts, the air heated by the cooling means is supplied to the position, thereby Occurrence can be suppressed.

According to the present invention, there is an effect that the first heat exchanger can exhibit sufficient heat exchange capability both during cooling and during heating.

It is the figure which showed the refrigerant circuit of the air conditioning apparatus which concerns on one Embodiment of this invention. It is the schematic of the air flow in the cooling unit of the air conditioning apparatus which concerns on one Embodiment of this invention. It is the schematic of the position which is easy to form frost in the 1st heat exchanger of the air conditioning apparatus which concerns on one Embodiment of this invention. It is the figure which showed the example of arrangement | positioning of the flow-path switching part of the air conditioning apparatus which concerns on one Embodiment of this invention. It is the figure which showed the example of arrangement | positioning of the flow-path switching part of the air conditioning apparatus which concerns on one Embodiment of this invention. It is the figure which showed the example of arrangement | positioning of the flow-path switching part of the air conditioning apparatus which concerns on one Embodiment of this invention. It is the figure which showed the flow of the refrigerant | coolant at the time of the heating in the air conditioning apparatus which concerns on one Embodiment of this invention. It is the figure which showed the flow of the refrigerant | coolant at the time of cooling in the air conditioning apparatus which concerns on one Embodiment of this invention. It is the figure which showed the refrigerant | coolant amount at the time of air_conditioning | cooling of the 1st heat exchanger in the air conditioning apparatus which concerns on one Embodiment of this invention, and the time of heating. It is the figure which showed the appropriate refrigerant | coolant amount range at the time of air_conditioning | cooling in the air conditioning apparatus which concerns on one Embodiment of this invention, and heating. It is the figure explaining the state of the refrigerant at the time of using the cooling part of the air harmony device concerning one embodiment of the present invention using the Mollier diagram. It is the figure which showed the refrigerant circuit of the heat pump type air conditioning harmony system concerning the invention of patent documents 1. It is the figure which showed the refrigerant | coolant amount at the time of the air_conditioning | cooling and heating of the 1st heat exchanger which concerns on the invention of patent document 1. FIG. It is the figure which showed the appropriate refrigerant | coolant amount range at the time of air_conditioning | cooling of the 1st heat exchanger which concerns on invention of patent document 1, and heating.

  An embodiment of the present invention will be described below with reference to FIG. FIG. 1 shows a refrigerant circuit of an air conditioner 1 according to an embodiment of the present invention. In FIG. 1, the solid line indicates the refrigerant flow during heating, and the dotted line indicates the refrigerant flow during cooling. Moreover, although the case where the air conditioning apparatus 1 which concerns on this embodiment is mounted in EV is demonstrated, it is not restricted to the case where it mounts in EV, Various air conditioning apparatuses, such as a gasoline vehicle, a household air conditioner, and a commercial air conditioner 1 is applicable.

The air conditioner 1 according to the present embodiment includes an HVAC unit (Heating
Ventilation and Air Conditioning Unit) 11, cooling refrigerant circuit 12 having first heat exchanger 38 (outdoor heat exchanger) and receiver 34, and sharing of first heat exchanger 38 and receiver 34 with cooling refrigerant circuit 12 A refrigerant circuit for heating 13, a plurality of flow path switching units provided in the cooling refrigerant circuit 12 and the heating refrigerant circuit 13 for switching the refrigerant flow path, and a control unit 15 for controlling the flow path switching unit. I have.

  The HVAC unit 11 includes a blower 21 that pumps air and an air mix damper 22 that adjusts the temperature of the conditioned air blown into the passenger compartment. Further, in the HVAC unit 11, a water / air heat exchanger 23 of the second heat exchange unit 31 provided in the cooling refrigerant circuit 12 and a third heat exchanger 24 provided in the heating refrigerant circuit 13 are arranged. . The HVAC unit 11 is provided, for example, in an instrument panel on the passenger compartment side, and is configured to selectively blow conditioned air into a passenger compartment from a plurality of outlets opened toward the passenger compartment. In the HVAC unit 11, the conditioned air supplied into the vehicle is heated by the water / air heat exchanger 23 during heating, and the conditioned air supplied into the vehicle is cooled by the third heat exchanger 24 during cooling.

  The blower 21 takes either outside air or inside air into the HVAC unit 11 and pumps it to the downstream side of the blower 21.

  The third heat exchanger 24 is provided on the downstream side of the air flow of the blower 21 and operates as an evaporator during cooling, thereby absorbing heat to the supplied air and lowering the temperature of the air. During heating, the third heat exchanger 24 is not supplied with a refrigerant, and therefore does not perform a heat absorbing action, and the supplied air is allowed to flow downstream.

  The air mix damper 22 is provided on the downstream side of the air flow of the third heat exchanger 24, and the amount of air flowing through the water / air heat exchanger 23 and the water / air heat exchanger are controlled by controlling the opening degree. 23 is adjusted to adjust the temperature of the conditioned air blown into the passenger compartment.

  The water / air heat exchanger 23 is provided on the downstream side of the air flow of the air mix damper 22 and heats the air by performing heat radiation to the supplied air during heating. During cooling, the water / air heat exchanger 23 is not supplied with a refrigerant, or even if the refrigerant is supplied, air is not supplied to the water / air heat exchanger 23 by the air mix damper 22, so that a heat dissipation action is performed. Absent. For this reason, the air supplied to the vehicle through the HVAC unit 11 is cooled by the third heat exchanger 24 during cooling in the HVAC unit 11 and heated by the water / air heat exchanger 23 during heating. The

  The heating refrigerant circuit 13 includes a compressor 30 that compresses the refrigerant, a second heat exchange unit 31, a three-way solenoid valve 33, a receiver 34, a cooling unit 35 that cools the refrigerant, and a first expansion that expands the refrigerant. A valve 36, a check valve 37, a first heat exchanger 38, and an on-off valve 39 are provided. The heating refrigerant circuit 13 realizes a heating function by circulating a cycle of compression, condensation, expansion, and evaporation with respect to the refrigerant filled in the circuit. As the on-off valve 39, various types of on-off valves such as a two-way solenoid valve can be applied.

  The compressor 30 compresses the refrigerant supplied from the first heat exchanger 38. Specifically, the intake port of the compressor 30 is connected to the first heat exchanger 38 via the pipe P8, the on-off valve 39 and the pipe P7, and the outlet of the compressor 30 is connected to the second heat via the pipe P1. It is connected to the exchange unit 31. In the compressor 30, the gas-phase refrigerant is supplied from the first heat exchanger 38 via the on-off valve 39, and the refrigerant is brought into a high-temperature and high-pressure state by compressing the gas-phase refrigerant and supplied to the second heat exchange unit 31. To do. The electric compressor 30 can be applied to various types such as a centrifugal type and an axial flow type.

The second heat exchange unit 31 is supplied with the refrigerant compressed by the compressor 30. Specifically, the inlet of the second heat exchange unit 31 is connected to the outlet of the compressor 30 via the pipe P1, and the outlet of the second heat exchange unit 31 is connected to the three-way solenoid valve 33 via the pipe P2. Connected to the first end.
The second heat exchange unit 31 includes a water / refrigerant heat exchanger 32, a water circulation path 51, a pump 52, and a water / air heat exchanger 23. The water / refrigerant heat exchanger 32 is provided in the HVAC unit 11.

  In the second heat exchange unit 31, in the water / refrigerant heat exchanger 32, heat exchange is performed between the high-temperature and high-pressure gas-phase refrigerant supplied from the compressor 30 and the circulating water circulating in the water circulation path 51, and the water circulation path The circulating water of 51 is heated. Then, the circulating water heated by the water / refrigerant heat exchanger 32 is supplied to the water / air heat exchanger 23 using the pump 52. In the water / air heat exchanger 23, the water / air heat exchanger 23 in the HVAC unit 11 is exchanged by performing heat exchange between the heated circulating water and the air supplied in the HVAC unit 11. Heat the flowing air. By performing heat exchange in the water / refrigerant heat exchanger 32, the refrigerant is dissipated and condensed. The condensed liquid phase refrigerant is supplied to the receiver 34 via the three-way solenoid valve 33.

In the present embodiment, the second heat exchange unit 31 includes the water / refrigerant heat exchanger 32, the water circulation path 51, the pump 52, and the water / air heat exchanger 23. However, the water / refrigerant heat exchanger The heat medium circulating between 32 and the water / air heat exchanger is not limited to water, and various heat media can be applied. Moreover, the 2nd heat exchange part 31 is good also as only a condenser instead of the said structure. In this case, the condenser is provided in the HAVC unit, and the high-temperature and high-pressure gas-phase refrigerant supplied from the compressor 30 is directly supplied to the condenser, and the liquid-phase refrigerant condensed by the condenser is three-way electromagnetically. The valve 33 is supplied to the receiver 34 through the first end and the second end.

  The receiver 34 is supplied with the refrigerant condensed in the second heat exchange unit 31. Specifically, the inlet of the receiver 34 is connected to the second end of the three-way solenoid valve 33 via the pipe P3, and the outlet of the receiver 34 is connected to the cooling unit 35 via the first pipe P4. In the receiver 34, the liquid phase refrigerant condensed by the second heat exchange unit 31 is supplied and temporarily stored in the receiver 34. Then, the liquid phase refrigerant is supplied to the cooling unit 35 from the outlet of the receiver 34.

  The cooling unit 35 is supplied with the refrigerant from the sieve and cools the refrigerant. Specifically, the inlet of the cooling unit 35 is connected to the receiver 34 via the first pipe P4, and the outlet of the cooling unit 35 is connected to the first expansion valve 36 via the second pipe P5. The cooling unit 35 cools the liquid-phase refrigerant supplied from the receiver 34 and supplies the cooled refrigerant to the first expansion valve 36. In addition, by using a supercooler as the cooling unit 35, the refrigerant supplied from the receiver 34 may be supercooled, and the supercooled refrigerant may be supplied to the first expansion valve 36.

  When the cooling unit 35 performs heat exchange between the refrigerant flowing inside the cooling unit 35 and the air flowing outside the cooling unit 35, as shown in FIG. The first heat exchanger 38 may be disposed upstream of the air flow. That is, when the refrigerant is cooled by the cooling unit 35, the air flowing outside the cooling unit 35 is heated, and the heated air is supplied to the first heat exchanger 38.

  By doing in this way, a part of inflow air of the 1st heat exchanger 38 will be heated by the cooling part 35, and since the average temperature of the air which passes the exterior of the 1st heat exchanger 38 becomes high, When the first heat exchanger 38 is used as an evaporator, the ability to evaporate the refrigerant can be improved. Further, instead of improving the evaporation capability of the first heat exchanger 38, the amount of refrigerant can be reduced while maintaining the capability, and the first heat exchanger 38 can be downsized. In particular, it is possible to deal with a case where there is a restriction on the location and volume of the air conditioner 1 such as when the air conditioner 1 is mounted on a car.

  Further, the cooling unit 35 may be disposed on the upstream side of the air flow of the first heat exchanger 38 and at a position where the saturation temperature of the refrigerant circulating in the first heat exchanger 38 is the lowest. Or it may be arrange | positioned in the upstream of the air flow of the 1st heat exchanger 38, and the position with the most liquid phase refrigerant | coolants which distribute | circulate in the 1st heat exchanger 38. FIG.

  When the first heat exchanger 38 is used as an evaporator, frost formation may occur in the first heat exchanger 38. As shown in FIG. 3, the position 38 b where frost formation is likely to occur in the first heat exchanger 38 depends on the state 38 a of the refrigerant flowing inside the first heat exchanger 38. Specifically, there is a high possibility that frost formation will occur at a position where the saturation temperature of the refrigerant flowing through the first heat exchanger 38 is the lowest or at a position where there is the largest amount of liquid-phase refrigerant flowing. For this reason, frost formation can be suppressed by arrange | positioning the cooling unit 35 so that the air heated with the cooling unit 35 may be supplied with respect to the position 38b where frost formation is easy to occur.

  The first expansion valve 36 depressurizes the refrigerant from the cooling unit 35. Specifically, the inlet of the first expansion valve 36 is connected to the cooling unit 35 via the second pipe P5, and the outlet of the first expansion valve 36 is connected to the first pipe via the third pipe P6 and the check valve 37. 1 It is connected to the heat exchanger 38. In the first expansion valve 36, the low-temperature liquid-phase refrigerant supplied from the cooling unit 35 is decompressed to bring the refrigerant into a low-temperature and low-pressure state. The low-temperature and low-pressure liquid-phase refrigerant is converted into the first heat exchanger 38. Supplied to.

A check valve 37 is provided on the third pipe P6. This is to prevent refrigerant from the first heat exchanger 38 from flowing into the first expansion valve 36 and the cooling unit 35 in the pipe P11 provided in the cooling refrigerant circuit 12 described later. Therefore, the refrigerant flow from the first expansion valve 36 to the first heat exchanger 38 becomes positive in the third pipe P6 during heating, and the refrigerant flow from the first heat exchanger 38 to the first expansion valve 36 during cooling. Since it becomes negative, backflow can be prevented.

  The first heat exchanger 38 is supplied with the refrigerant from the first expansion valve 36. Specifically, one end of the first heat exchanger 38 is connected to the first expansion valve 36 via the third pipe P6, and the other end of the first heat exchanger 38 is connected to the on-off valve 39 via the pipe P7. Connected to. In the first heat exchanger 38, heat is generated between the low-temperature and low-pressure liquid-phase refrigerant supplied from the first expansion valve 36 that flows inside the first heat exchanger 38 and the air that flows outside the first heat exchanger 38. Exchange is performed to heat the low-temperature and low-pressure liquid-phase refrigerant into a gas-phase refrigerant. Then, the gas phase refrigerant is supplied to the compressor 30 via the on-off valve 39. That is, the first heat exchanger 38 functions as an evaporator during heating.

The cooling refrigerant circuit 12 includes a compressor 30 that compresses refrigerant, a second heat exchange unit 31, a three-way electromagnetic valve 33, a first heat exchanger 38, a receiver 34, an on-off valve 40, and a second expansion. A valve 41 and a third heat exchanger 24 are provided. The cooling refrigerant circuit 12 realizes a cooling function by circulating a cycle of compression, condensation, expansion, and evaporation with respect to the refrigerant filled in the circuit. During cooling, the first heat exchanger 38 functions as a condenser. The third heat exchanger 24 functions as an evaporator.
The compressor 30, the second heat exchange unit 31, the first heat exchanger 38, and the receiver 34 are configured to be shared with the heating refrigerant circuit 13. For this reason, in the configuration of the cooling refrigerant circuit 12, the configuration common to the heating refrigerant circuit 13 will be described in a simplified manner.
The cooling refrigerant circuit 12 only needs to share at least the first heat exchanger 38 with the heating refrigerant circuit 13, and is not limited to the above configuration. As the on-off valve 40, various types of on-off valves such as a two-way solenoid valve can be applied.

  The three-way solenoid valve 33 has a first end connected to the second heat exchange unit 31 via a pipe P2 and a third end connected to the other end of the first heat exchanger 38 via a pipe P10. And the one end side of the 1st heat exchanger 38 is connected to the inlet_port | entrance of the receiver 34 via piping P11, and the outlet of the receiver 34 is connected to the on-off valve 40 via piping P12. Also. The on-off valve 40 is connected to the inlet of the second expansion valve 41 via the pipe P13. The outlet of the second expansion valve 41 is connected to one end of the third heat exchanger 24, and the other end of the third heat exchanger 24 is connected to the suction port of the compressor 30 via the pipe P14.

  A plurality of flow path switching units are provided in the cooling refrigerant circuit 12 and the heating refrigerant circuit 13 in order to switch the refrigerant flow path. In the present embodiment, in order to switch between the cooling refrigerant circuit 12 and the heating refrigerant circuit 13, a three-way electromagnetic valve 33 is provided as a flow path switching unit for the pipe P2, the pipe P3, and the pipe P10, and the on-off valve 39 Are provided for the pipe P7 and the pipe P8, the open / close valve 40 is provided for the pipe P12 and the pipe P13, and the first expansion valve 36 has a flow path opening / closing function as a flow path switching unit. It is said. In addition, about arrangement | positioning etc. of a flow-path switching part, it is not limited to the said example, What is necessary is just the arrangement | positioning which can switch between the refrigerant circuit 12 for cooling, and the refrigerant circuit 13 for heating. Further, the valve employed in the flow path switching unit is not limited to the type of the valve, and can be appropriately selected.

  The control unit 15 controls the flow path switching unit. In particular, the control unit 15 controls the flow path switching unit to supply the refrigerant from the first heat exchanger 38 to the receiver 34 without passing through the cooling unit 35 at the time of cooling, and from the receiver 34 at the time of heating. Is supplied to the first heat exchanger 38 via the cooling unit 35. That is, the refrigerant is supplied to the cooling unit 35 only during cooling.

Specifically, during heating, the control unit 15 opens the first end and the second end of the three-way solenoid valve 33, closes the third end, opens the on-off valve 39, closes the on-off valve 40, 1 The expansion valve 36 is opened. Thereby, the refrigerant circuit 13 for heating is comprised and the refrigerant cycle for heating is controlled.
Further, the controller 15 opens the first end and the third end of the three-way solenoid valve 33, closes the second end, closes the on-off valve 39, opens the on-off valve 40, and opens the first expansion valve during cooling. 36 is closed. Thereby, the cooling refrigerant circuit 12 is configured, and the cooling refrigerant cycle is controlled.

  As a flow path switching unit, as shown in FIG. 4, instead of providing the first expansion valve 36 with a flow path opening / closing function, an opening / closing valve 42 may be provided on the first pipe P4 or the second pipe P5. Good. In this case, during heating, the control device opens the first end and the second end of the three-way solenoid valve 33, closes the third end, opens the on-off valve 39, closes the on-off valve 40, and closes the first end. The heating refrigerant circuit 13 may be configured by opening the on-off valve 42 instead of the expansion valve 36. During cooling, the first end and the third end of the three-way solenoid valve 33 are opened, the second end is closed, the on-off valve 39 is closed, the on-off valve 40 is opened, and an opening / closing instead of the first expansion valve 36 is performed. The cooling refrigerant circuit 12 may be configured by closing the valve 42. As the on-off valve 42, various types of on-off valves such as a two-way solenoid valve can be applied.

  Further, as shown in FIG. 5, the second expansion valve 41 may be provided with a flow path opening / closing function instead of the opening / closing valve 40 as a flow path switching unit. In this case, at the time of heating, the control device opens the first end and the second end of the three-way solenoid valve 33, closes the third end, opens the on-off valve 39, opens the first expansion valve 36, The heating refrigerant circuit 13 may be configured by closing the second expansion valve 41 instead of the on-off valve 40. During cooling, the first end and the third end of the three-way solenoid valve 33 are opened, the second end is closed, the on-off valve 39 is closed, the first expansion valve 36 is closed, and the first valve instead of the on-off valve 40 is closed. The cooling refrigerant circuit 12 may be configured by opening the two expansion valve 41.

  In addition, as shown in FIG. 6, as the flow path switching unit, instead of providing the first expansion valve 36 with a flow path opening / closing function, an opening / closing valve 42 is provided on the first pipe P4 or the second pipe P5, Instead of 40, the second expansion valve 41 may have a channel opening / closing function. In this case, during heating, the control device opens the first end and the second end of the three-way solenoid valve 33, closes the third end, opens the on-off valve 39, opens the on-off valve 42, and opens the second The heating refrigerant circuit 13 may be configured by closing the expansion valve 41. During cooling, the first and third ends of the three-way solenoid valve 33 are opened, the second end is closed, the on-off valve 39 is closed, the on-off valve 42 is closed, and the second expansion valve 41 is opened. Accordingly, the cooling refrigerant circuit 12 may be configured.

  Next, the operation | movement at the time of the heating in the air conditioning apparatus 1 which concerns on this embodiment is demonstrated. FIG. 7 is a diagram illustrating a refrigerant flow during heating in the air-conditioning apparatus 1 according to the present embodiment. As described above, the state of the flow path switching unit is determined by the control unit 15 by opening the first end and the second end of the three-way solenoid valve 33, closing the third end, opening the on-off valve 39, and opening the on-off valve 39. It is assumed that 40 is closed and the first expansion valve 36 is opened.

  The refrigerant is compressed in the compressor 30 and becomes a high temperature and high pressure state. And a refrigerant | coolant is supplied to the 2nd heat exchange part 31 via the piping P1, and in the water / refrigerant heat exchanger 32 which the 2nd heat exchange part 31 has, heat exchange between the circulating water in the water circulation path 51 is carried out. It is condensed by doing. The condensed refrigerant is supplied to the receiver 34 via the pipe P2, the first and second ends of the three-way solenoid valve 33, and the pipe P3. The refrigerant is temporarily accumulated in the receiver 34, and then supplied to the cooling unit 35 via the first pipe P4 to be cooled. The refrigerant cooled by the cooling unit 35 is supplied to the first expansion valve 36 and depressurized, so that the refrigerant is in a low temperature and low pressure state. The refrigerant in a low-temperature and low-pressure state is supplied to the first heat exchanger 38, and heat is exchanged with the air passing through the outside of the first heat exchanger 38 to be heated. The heated refrigerant is supplied to the compressor 30 via the pipes P7 and P8 and the on-off valve 39.

  By performing such a refrigerant cycle, the thermal energy of the air passing through the outside of the first heat exchanger 38 moves to the second heat exchange unit 31 via the refrigerant. In the second heat exchanging unit 31, the heat energy moves from the water / refrigerant heat exchanger 32 to the water / air heat exchanger 23 in the HVAC unit 11 through the water circulation path 51. For this reason, in the water / air heat exchanger 23 in the HVAC unit 11, the air supplied into the vehicle can be warmed using thermal energy.

  Next, the operation | movement at the time of the cooling in the air conditioning apparatus 1 which concerns on this embodiment is demonstrated. FIG. 8 is a diagram illustrating a refrigerant flow during cooling in the air-conditioning apparatus 1 according to the present embodiment. As described above, the state of the flow path switching unit is determined by the control unit 15 by opening the first and third ends of the three-way solenoid valve 33, closing the second end, closing the on-off valve 39, and closing the on-off valve. 40 is opened and the first expansion valve 36 is closed.

  The refrigerant is compressed in the compressor 30 and becomes a high-temperature and high-pressure refrigerant. And a refrigerant | coolant is supplied to the 2nd heat exchange part 31 via the piping P1, and in the water / refrigerant heat exchanger 32 which the 2nd heat exchange part 31 has, heat exchange between the circulating water in the water circulation path 51 is carried out. Condenses by being done. The condensed refrigerant is supplied to the first heat exchanger 38 via the pipe P2, the first and third ends of the three-way solenoid valve 33, and the pipe P10, and between the outside air passing through the first heat exchanger 38. Heat exchange occurs and condenses. The condensed refrigerant is supplied to the receiver 34 via the pipe P11, temporarily accumulated in the receiver 34, and then supplied to the second expansion valve 41 via the pipe P12 and the on-off valve 40. The refrigerant is depressurized by the second expansion valve 41 to be in a low pressure and low temperature state. The refrigerant in the low temperature and low pressure state is supplied to the third heat exchanger 24, and heat is exchanged with the air passing through the third heat exchanger 24 to be heated. The heated refrigerant is supplied to the compressor 30 via the pipe P14.

  Even during cooling, the heat energy of the high-temperature and high-pressure refrigerant compressed by the compressor 30 in the second heat exchange unit 31 is exchanged for water / air heat via the water / refrigerant heat exchanger 32 and the water circulation path 51. The air supplied to the vehicle in the HVAC unit 11 may be warmed because it moves to the vessel 23, but the air mix damper 22 is controlled so that the air upstream of the water / air heat exchanger 23 is discharged. By bypassing everything and preventing the water / air heat exchanger 23 from passing through, the air cooled by the third heat exchanger 24 is prevented from being heated. During cooling, the water / refrigerant heat exchanger 32 is not operated, and the second heat exchange unit 31 does not perform heat exchange between the refrigerant supplied from the compressor 30 and the circulating water in the water circulation path 51. It is good.

  By performing such a cycle, the heat energy of the air in the HVAC unit 11 passing through the third heat exchanger 24 is transferred to the first heat exchanger 38 via the refrigerant. Then, the heat energy is moved to the outside air by the first heat exchanger 38. That is, the third heat exchanger 24 cools the air supplied into the vehicle.

  As described above, in the air-conditioning apparatus 1 according to this embodiment, the cooling refrigerant circuit 12 and the heating refrigerant circuit 13 share the first heat exchanger 38 and use the cooling unit 35 only during heating. Since the refrigerant cooled by the above is supplied to the first heat exchanger 38, the optimum refrigerant amount when the first heat exchanger 38 is used as an evaporator during heating can be increased. That is, as shown in FIGS. 9 and 10, by excessively cooling the refrigerant supplied to the first heat exchanger 38 that operates as an evaporator, as shown in FIGS. 9 and 10, the amount of refrigerant when the cooling unit 35 is not provided in the heating refrigerant circuit 13. 13 and 14 showing the above, the range of the optimum refrigerant amount when the first heat exchanger 38 is used as an evaporator during heating can be increased.

  Therefore, an appropriate refrigerant amount range of the first heat exchanger 38 when the first heat exchanger 38 is used as a condenser and a first heat exchanger 38 when the first heat exchanger 38 is used as an evaporator. The refrigerant amount range that overlaps with the appropriate refrigerant amount range can be obtained, and the refrigerant amount to be charged in the air conditioner 1 is designed within the overlapped refrigerant amount range, thereby condensing the first heat exchanger 38. Regardless of whether it is used as an evaporator or an evaporator, the heat exchange capability can be sufficiently exhibited.

  Further, by supplying the excessively cooled refrigerant by the cooling unit 35 to the first heat exchanger 38 functioning as an evaporator, as shown in FIG. 11, the thirst degree in the first heat exchanger 38 is changed from g. It is possible to reduce the flow rate of the refrigerant by changing to f, that is, the degree of thirst. For this reason, it is possible to keep a large amount of the liquid-phase refrigerant flowing through the first heat exchanger 38. As a result, the pressure loss and temperature gradient at the inlet and outlet of the first heat exchanger 38 are reduced. Therefore, partial frost formation in the first heat exchanger 38 can be suppressed.

  Further, when the cooling unit 35 is disposed on the upstream side of the air flow of the first heat exchanger 38, the air flowing outside the cooling unit 35 can be heated when the cooling unit 35 cools the refrigerant. The heated air can be supplied to the first heat exchanger 38. That is, a part of the inflow air of the first heat exchanger 38 is heated by the cooling unit 35, and the average temperature of the air passing outside the first heat exchanger 38 is increased, so that the first heat exchanger When 38 is used as an evaporator, the ability to evaporate the refrigerant can be improved. Further, instead of improving the evaporation capability of the first heat exchanger 38, the amount of refrigerant can be reduced while maintaining the capability, and the first heat exchanger 38 can be downsized. In particular, it is possible to deal with a case where there is a restriction on the location and volume of the air conditioner 1 such as when the air conditioner 1 is mounted on a car.

  The cooling unit 35 is located upstream of the air flow of the first heat exchanger 38 and is disposed at a position where the saturation temperature of the refrigerant circulating in the first heat exchanger 38 is lowest, or the first heat When it arrange | positions in the position with the most liquid phase refrigerant | coolants which distribute | circulate in the exchanger 38, the frost formation in the 1st heat exchanger 38 can be suppressed. That is, when the first heat exchanger 38 is used as an evaporator, frost formation may occur in the first heat exchanger 38, but frost formation is likely to occur in the first heat exchanger 38. The position depends on the state of the refrigerant flowing inside the first heat exchanger 38. Specifically, there is a high possibility that frost formation will occur at a position where the saturation temperature of the refrigerant flowing through the first heat exchanger 38 is the lowest or at a position where there is the largest amount of liquid-phase refrigerant flowing. For this reason, frost formation can be suppressed by arrange | positioning the cooling unit 35 so that the air heated with the cooling unit 35 may be supplied with respect to the position where frost formation is easy to occur.

  The air conditioner 1 according to the present embodiment configures the heating refrigerant circuit 13 or the heating refrigerant circuit 13 by switching the flow path by the flow path switching unit, and the heating refrigerant circuit 13 and the cooling refrigerant circuit. Although 12 is supposed to share some of the constituent elements, it is possible to independently configure only the heating refrigerant circuit 13. In this case, an excessively cooled refrigerant is supplied to the first heat exchanger 38 by providing the cooling unit 35 downstream of the refrigerant flow of the receiver 34 and upstream of the refrigerant flow of the expansion valve. can do.

  In addition, since the air conditioning apparatus 1 which concerns on this embodiment demonstrated and demonstrated the vehicle-mounted air conditioning apparatus, the water / air heat which the 2nd heat exchange part 31 which functions as a condenser in the HVAC unit 11 has at the time of heating is included. It is set as the structure provided independently with the exchanger 23 and the 3rd heat exchanger 24 which functions as an evaporator at the time of air_conditioning | cooling. However, in addition to the vehicle-mounted air conditioner, other air conditioners 1 such as home air conditioners and commercial air conditioners may share the condenser and the evaporator.

1: Air conditioner 11: HVAC unit 12: Cooling refrigerant circuit 13: Heating refrigerant circuit 15: Control unit 21: Blower 22: Air mix damper 23: Water / air heat exchanger 24: Third heat exchanger 30: Compressor 31: 2nd heat exchange part 32: Water / refrigerant heat exchanger 33: Three-way solenoid valve 34: Receiver 35: Cooling part 36: First expansion valve 37: Check valve 38: First heat exchangers 39, 40 42: On-off valve 41: Second expansion valve 51: Water circulation path 52: Pump

Claims (9)

A cooling refrigerant circuit having a first heat exchanger and a receiver;
A heating refrigerant circuit sharing the first heat exchanger and the receiver with the cooling refrigerant circuit;
A plurality of flow path switching means provided in the cooling refrigerant circuit and the heating refrigerant circuit to switch the flow path of the refrigerant;
Control means for controlling the flow path switching means,
The heating refrigerant circuit is:
A compressor for compressing the refrigerant supplied from the first heat exchanger;
Second heat exchange means to which the refrigerant compressed by the compressor is supplied;
The receiver to which the refrigerant condensed by the second heat exchange means is supplied;
A cooling means for supplying the refrigerant from the receiver and cooling the refrigerant;
A first expansion valve for depressurizing the refrigerant from the cooling means;
The first heat exchanger to which the refrigerant from the first expansion valve is supplied,
The control means controls the flow path switching means to supply the refrigerant from the first heat exchanger to the receiver without passing through the cooling means during cooling, and to supply the refrigerant from the receiver during heating. An air conditioner that is supplied to the first heat exchanger via the cooling means. The heating refrigerant circuit is:
A first pipe for supplying the refrigerant from the receiver to the first expansion valve via the cooling means;
A first on-off valve as the flow path switching means provided in the first pipe,
The cooling refrigerant circuit includes:
A second expansion valve to which the refrigerant from the receiver is supplied through a second pipe;
A second on-off valve as the flow path switching means provided in the second pipe,
The air conditioner according to claim 1, wherein the control means closes the first on-off valve during cooling and closes the second on-off valve during heating. The heating refrigerant circuit includes a first pipe that supplies the refrigerant from the receiver to the first expansion valve via the cooling means;
An on-off valve as the flow path switching means provided in the first pipe,
The cooling refrigerant circuit includes a second expansion valve to which the refrigerant from the receiver is supplied through a second pipe,
The second expansion valve has a channel opening / closing function as the channel switching means,
The air conditioner according to claim 1, wherein the control means closes the on-off valve during cooling and closes the second expansion valve during heating. The heating refrigerant circuit includes a first pipe that supplies the refrigerant from the receiver to the first expansion valve via the cooling means,
The cooling refrigerant circuit includes a second expansion valve to which the refrigerant from the receiver is supplied through a second pipe;
An on-off valve as the flow path switching means provided in the second pipe,
The first expansion valve has a channel opening / closing function as the channel switching means,
The air conditioner according to claim 1, wherein the control means closes the first expansion valve during cooling and closes the on-off valve during heating. The cooling refrigerant circuit includes a second expansion valve to which the refrigerant from the receiver is supplied,
Each of the first expansion valve and the second expansion valve has a flow path opening / closing function as the flow path switching means,
The air conditioner according to claim 1, wherein the control means closes the first expansion valve during cooling and closes the second expansion valve during heating.   Appropriate refrigerant amount range of the first heat exchanger when the first heat exchanger is used as a condenser, and appropriate refrigerant of the first heat exchanger when the first heat exchanger is used as an evaporator The air conditioner according to any one of claims 1 to 5, wherein a refrigerant amount within a refrigerant amount range that overlaps with the amount range is filled.   The air conditioning apparatus according to any one of claims 1 to 6, wherein the cooling means is disposed on the upstream side of the air flow of the first heat exchanger.   The air conditioning according to claim 7, wherein the cooling means is disposed upstream of the air flow of the first heat exchanger and at a position where the saturation temperature of the refrigerant circulating in the first heat exchanger is lowest. apparatus.   The air conditioner according to claim 7, wherein the cooling unit is disposed upstream of the air flow of the first heat exchanger, and is disposed at a position where the liquid phase refrigerant circulating in the first heat exchanger is the largest.

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