WO2006003925A1 - 冷凍装置及び空気調和装置 - Google Patents
冷凍装置及び空気調和装置 Download PDFInfo
- Publication number
- WO2006003925A1 WO2006003925A1 PCT/JP2005/011930 JP2005011930W WO2006003925A1 WO 2006003925 A1 WO2006003925 A1 WO 2006003925A1 JP 2005011930 W JP2005011930 W JP 2005011930W WO 2006003925 A1 WO2006003925 A1 WO 2006003925A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- refrigerant
- heat source
- source side
- heat exchanger
- circuit
- Prior art date
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B39/00—Evaporators; Condensers
- F25B39/02—Evaporators
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F3/00—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems
- F24F3/06—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems characterised by the arrangements for the supply of heat-exchange fluid for the subsequent treatment of primary air in the room units
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B31/00—Compressor arrangements
- F25B31/002—Lubrication
- F25B31/004—Lubrication oil recirculating arrangements
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
- F28D9/00—Heat-exchange apparatus having stationary plate-like or laminated conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B2341/00—Details of ejectors not being used as compression device; Details of flow restrictors or expansion valves
- F25B2341/001—Ejectors not being used as compression device
- F25B2341/0016—Ejectors for creating an oil recirculation
Definitions
- the present invention relates to a refrigeration apparatus and an air conditioner, and more particularly to a refrigeration apparatus and an air conditioner including a refrigerant circuit having an evaporator configured to allow refrigerant to flow in from below and flow out from above. .
- a refrigerant evaporator there is a refrigeration apparatus provided with a vapor compression refrigerant circuit having a heat exchange configured such that a refrigerant flows in a lower force and an upper force flows out (for example, a patent) (Refer to Reference 1.)
- the specific gravity is lower than that of the refrigerant in order to prevent the refrigeration oil from accumulating in the evaporator, so it is separated into two layers and floats above the liquid level of the refrigerant.
- Refrigerating machine oil accumulated in a hot state is extracted near the refrigerant level and returned to the suction side of the compressor.
- a refrigeration apparatus including a vapor compression refrigerant circuit
- vapor compression having a heat source side refrigerant circuit having a plurality of heat source side heat exchanges and a plurality of utilization side refrigerant circuits connected to the heat source side refrigerant circuit.
- the flow rate of the refrigerant flowing into each heat source side heat exchanger can be adjusted. Is provided with a heat source side expansion valve.
- the air conditioning load of the plurality of use side refrigerant circuits as a whole decreases.
- the heat source side expansion valve is controlled to reduce the evaporation capacity by reducing the opening of the heat source side expansion valve.
- Heat source side heat exchange functioning as an evaporator by closing a part of the valve to reduce the evaporation capacity, or by making some of the heat source side heat exchangers function as condensers Control is performed to reduce the evaporation capacity by offsetting the evaporation capacity of the heat exchange on the heat source side that functions as an evaporator.
- the opening degree of the heat source side expansion valve connected to the heat source side heat exchanger is reduced as the air conditioning load of the entire plurality of usage side refrigerant circuits decreases. By doing so, the amount of liquid refrigerant that accumulates in the heat source side heat exchanger is increased to reduce the effective heat transfer area, thereby reducing the condensation capacity.
- Patent Document 1 Japanese Patent Application Laid-Open No. 63-204074
- Patent Document 2 JP-A-3-260561
- Patent Document 3 Japanese Patent Laid-Open No. 3-129259
- the heat exchanger such as a plate heat exchanger configured so that the refrigerant flows in from the lower side and flows out from the upper side when it functions as the refrigerant evaporator
- the heat source side heat exchanger In this case, in order to prevent refrigeration oil from accumulating in the heat source side heat exchanger, it is necessary to maintain the liquid level of the refrigerant in the heat source side heat exchanger at a certain level or higher.
- the opening degree of the heat source side expansion valve Even if an attempt is made to reduce the amount of refrigerant flowing through the heat source side heat exchanger by reducing the size of the heat source side heat exchanger, the opening degree of the heat source side expansion valve is made too small due to the restriction of the coolant level in the heat source side heat exchanger. As a result, it is not possible to sufficiently control the evaporation capacity only by adjusting the opening of the heat source side expansion valve. As a result, some of the heat source side expansion valves are closed to function as an evaporator.
- Heat source side heat exchange that functions as an evaporator by reducing evaporation capacity by reducing the number of heat exchangers, or by making some of the heat source side heat exchanges ⁇ function as condensers Offsets the evaporation capacity of Therefore, it is necessary to control to reduce the evaporation capacity.
- the heat source side heat exchanger when the heat source side heat exchanger is caused to function as a refrigerant condenser by providing a pressure circuit in the refrigerant circuit, the use side refrigerant is decompressed over the heat source side expansion valve.
- the refrigerant sent from the heat source side expansion valve to the user side refrigerant circuit becomes a gas-liquid two-phase flow, and the force is also on the heat source side.
- the opening of the expansion valve decreases, the gas fraction of the refrigerant after the high-pressure gas refrigerant is merged from the pressurization circuit increases, and drift occurs between the multiple use-side refrigerant circuits.
- the opening degree of the heat source side expansion valve cannot be made sufficiently small.
- An object of the present invention is to provide a refrigeration apparatus and an air conditioning apparatus having a refrigerant circuit having an evaporator configured such that a refrigerant flows into a lower force and flows out into an upper force. The purpose of this is to expand the control range when controlling the pressure with the expansion valve.
- a refrigeration apparatus according to a first invention includes a refrigerant circuit and an oil return circuit.
- the refrigerant circuit is configured by connecting a compression mechanism, a condenser, an expansion valve, and an evaporator configured to allow the refrigerant to flow into the lower force and to flow out into the upper force, and 30 ° C or less.
- the combined refrigeration oil and refrigerant are used in the temperature range of V and not separated into two layers.
- the oil return circuit is connected to the lower part of the evaporator, and returns the refrigeration oil accumulated in the evaporator to the compression mechanism together with the refrigerant.
- This refrigeration apparatus is provided with a refrigerant circuit having an evaporator configured such that the refrigerant flows in from the lower side and flows out from the upper side, and the refrigerating machine oil and refrigerant used in the refrigerant circuit are 30 ° C.
- Combined refrigeration oil and refrigerant are used in the following temperature range without separating into two layers.
- the evaporating temperature of the refrigerant in the evaporator is a temperature of 30 ° C. or lower when water, air, or brine is used as the heat source.
- the refrigerating machine oil is accumulated in the evaporator in a state where it is mixed with the refrigerant that does not accumulate in a state where it floats on the liquid level of the refrigerant in the evaporator.
- the refrigerating machine oil accumulated in the evaporator is returned to the compression mechanism together with the refrigerant by an oil return circuit connected to the lower part of the evaporator.
- an oil return circuit connected to the lower part of the evaporator.
- control is performed to reduce the evaporation capacity of the evaporator by reducing the opening of the expansion valve in accordance with the refrigeration load.
- the liquid level of the cooling medium in the evaporator decreases. Even so, since the refrigerating machine oil does not accumulate in the evaporator, it is possible to expand the control range when the evaporation capacity of the evaporator is controlled by the expansion valve.
- the refrigeration apparatus according to the second invention is the refrigeration apparatus according to the first invention, wherein the refrigerating machine oil and the refrigerant used in the refrigerant circuit are in a temperature range of 5 ° C or lower! This is a combination of refrigerating machine oil and refrigerant without separation.
- the refrigeration apparatus according to the third invention is similar to the refrigeration apparatus according to the second invention, and the combination of the refrigerating machine oil and the refrigerant used in the refrigerant circuit is ether oil and R410A.
- ether oil is used as the refrigerating machine oil
- R410A is used as the refrigerant. This combination of refrigerating machine oil and refrigerant does not separate into two layers in a temperature range of 5 ° C or lower, but even in such a case, refrigerating machine oil can be prevented from accumulating in the evaporator.
- a refrigeration apparatus is the refrigeration apparatus according to any one of the first to third inventions, wherein the refrigeration apparatus is returned to the compression mechanism from the lower part of the heat source side heat exchanger through the oil return circuit.
- a differential pressure increasing mechanism that increases the differential pressure until the machine oil and the refrigerant are merged is further provided.
- the flow rates of the refrigerating machine oil and the refrigerant returned from the lower part of the evaporator to the compression mechanism through the oil return circuit are such that the lower part of the evaporator and the compression mechanism are
- the pressure loss in the oil return circuit where the pressure loss in the pipe between the evaporator and the refrigerant outlet side force compression mechanism to the suction side of the evaporator is small.
- the differential pressure increasing mechanism since the differential pressure increasing mechanism is provided, the flow rate of the refrigeration oil and refrigerant returned to the lower force compression mechanism of the evaporator through the oil return circuit can be increased.
- the refrigerating machine oil and the refrigerant having a flow rate sufficient to prevent the refrigerating machine oil from being accumulated in the evaporator can be reliably returned to the compression mechanism from the lower part of the evaporator through the oil return circuit.
- a refrigeration apparatus includes a refrigerant circuit and an oil return circuit.
- the refrigerant circuit has a compression mechanism, a condenser, an expansion valve, and the refrigerant flows into the lower force and flows out into the upper force.
- the combination of the refrigerating machine oil and the refrigerant that is not separated into two layers is used in the evaporator.
- the oil return circuit is connected to the lower part of the evaporator and returns the refrigeration oil accumulated in the evaporator to the compression mechanism together with the refrigerant.
- This refrigeration apparatus includes a refrigerant circuit having an evaporator configured so that the refrigerant flows in from the lower side and flows out from the upper side, and as the refrigerating machine oil and refrigerant used in the refrigerant circuit, However, it uses a combination of refrigerating machine oil and refrigerant that cannot be separated into two layers. For this reason, in this refrigeration system, the refrigerating machine oil is stored in the evaporator in a state where it is mixed with the refrigerant that does not accumulate on the liquid level of the refrigerant in the evaporator under the condition of the evaporation temperature of the refrigerant in the evaporator. It will be accumulated in.
- the refrigerating machine oil accumulated in the evaporator is returned to the compression mechanism together with the refrigerant by an oil return circuit connected to the lower part of the evaporator. Therefore, unlike the conventional refrigeration system, it is not necessary to maintain the liquid level of the refrigerant in the heat source side heat exchanger at a certain level or higher in order to prevent the refrigerating machine oil from being accumulated in the evaporator. .
- the air conditioner according to the sixth invention comprises a refrigerant circuit and an oil return circuit.
- the refrigerant circuit has a compression mechanism, a heat source side heat exchanger configured so that the refrigerant flows into the lower force and flows out from the upper side when functioning as an evaporator, and the heat source side expansion valve.
- a heat source side refrigerant circuit configured to be connected is configured by connecting a plurality of usage side refrigerant circuits configured by connecting a usage side heat exchanger and a usage side expansion valve to a 30 ° C
- a combination of refrigerating machine oil and refrigerant is used in the following temperature range without separating into two layers.
- the oil return circuit is connected to the lower part of the heat source side heat exchanger and returns the refrigeration oil accumulated in the heat source side heat exchanger to the compression mechanism together with the refrigerant.
- the heat source side refrigerant circuit when functioning as an evaporator, the heat source side refrigerant circuit having a heat source side heat exchanger configured to allow the refrigerant to flow into the lower force and flow out from the upper side, and a plurality of use side refrigerants And a refrigerant circuit configured to be connected to the circuit.
- a combination of refrigeration oil and refrigerant that does not separate into two layers in the temperature range of 30 ° C or less is used.
- the evaporation temperature of the refrigerant in the heat source side heat exchanger is 30 ° C. or less when water, air, or brine is used as the heat source.
- the refrigerating machine oil accumulates in the heat source side heat exchanger in a mixed state with the refrigerant that does not accumulate in the state of floating on the liquid level of the refrigerant in the heat source side heat exchanger. .
- the refrigerating machine oil accumulated in the heat source side heat exchanger is returned to the compression mechanism together with the refrigerant by an oil return circuit connected to the lower part of the heat source side heat exchanger.
- the refrigerant level in the heat source side heat exchanger is maintained at a certain level or higher in order to prevent the refrigeration oil from accumulating in the heat source side heat exchanger. There is no need to do it.
- control is performed to reduce the evaporation capability of the heat source side heat exchanger by reducing the opening of the heat source side expansion valve in accordance with the air conditioning load of the plurality of use side refrigerant circuits.
- refrigeration oil does not accumulate in the heat source side heat exchange even if the refrigerant level in the heat source side heat exchange decreases, so the evaporation capacity of the heat source side heat exchange is expanded on the heat source side. It is possible to expand the control range when controlling by a valve.
- a plurality of heat source side heat exchangers are provided to evaporate the heat source side heat exchange.
- the evaporation capacity can be reduced, or multiple heat source side Make a part of heat exchange ⁇ function as a condenser Since there is no need to control to reduce the evaporation capacity by offsetting the evaporation capacity of the heat source side heat exchanger that functions as an evaporator, a wide range of evaporation capacity can be controlled by a single heat source side heat exchanger. You will be able to get
- a refrigeration apparatus is the air conditioner according to the sixth aspect of the invention, wherein the refrigerating machine oil and the refrigerant used in the refrigerant circuit are in a temperature range of 5 ° C or lower! Do not separate into layers! Combined refrigeration oil and refrigerant.
- An air conditioner according to an eighth invention is the air conditioner according to the seventh invention, wherein the combination of refrigerating machine oil and refrigerant used in the refrigerant circuit is ether oil and R41 OA.
- ether oil is used as refrigerating machine oil and R410A is used as refrigerant.
- R410A is used as refrigerant.
- An air conditioner according to a ninth invention is the air conditioner according to any of the sixth to eighth inventions, wherein the refrigeration is returned to the lower force compression mechanism of the heat source side heat exchanger through the oil return circuit. It is further equipped with a differential pressure increasing mechanism that increases the differential pressure until it merges with machine oil and refrigerant.
- the flow rates of the refrigerating machine oil and the refrigerant returned to the compression mechanism from the lower side of the heat source side heat exchanger functioning as a evaporator through the oil return circuit are reduced. Because it is determined according to the pressure loss between the lower part of the heat source side heat exchanger ⁇ that functions as an evaporator in the oil return circuit and the compression mechanism, for example, it functions as an evaporator. When the pressure loss in the oil return circuit is small, the pressure loss in the piping between the heat source side heat exchange and the refrigerant outlet side of the heat source side heat exchange to the suction side of the compression mechanism is small, etc.
- the refrigerating machine oil and refrigerant at a flow rate sufficient to prevent the refrigerating machine oil from accumulating in the heat source side heat exchange may not be able to return the lower force of the heat source side heat exchange to the compression mechanism through the oil return circuit. Can occur.
- the differential pressure increasing mechanism by providing the differential pressure increasing mechanism, the flow rate of the refrigerating machine oil and refrigerant returned from the lower part of the heat source side heat exchanger to the compression mechanism through the oil return circuit can be increased. Therefore, the refrigeration oil and refrigerant at a flow rate sufficient to prevent the refrigeration oil from accumulating in the heat source side heat exchange are surely supplied to the lower force of the heat source side heat exchange ⁇ through the oil return circuit. It can be returned to the compression mechanism.
- An air conditioner according to a tenth aspect of the present invention is the air conditioner according to any of the sixth to ninth aspects, wherein the oil return circuit has an on-off valve.
- the on-off valve is closed when the heat source side heat exchanger functions as a condenser, and is opened when the heat source side heat exchanger functions as an evaporator.
- an on / off valve is provided in the oil return circuit, and when heat exchange on the heat source side functions as a condenser, operation is performed with the on / off valve closed to condense in the heat source side heat exchanger. It is possible to prevent the amount of refrigerant sent to the usage-side refrigerant circuit from being reduced.
- An air conditioner according to an eleventh aspect of the present invention is the air conditioner according to the tenth aspect of the invention, wherein the on-off valve is opened when the opening of the heat source side expansion valve becomes a predetermined opening or less.
- this air conditioner it is not necessary to use an oil return circuit until the refrigerant level in the heat source side heat exchanger reaches a certain level above which no refrigerating machine oil accumulates.
- An air conditioner according to a twelfth aspect of the present invention is the air conditioner according to any of the sixth to eleventh aspects of the invention, wherein the heat source side heat exchanger is a flow rate of the refrigerant flowing in the heat source side heat exchanger. Regardless of the amount of water, a certain amount of water is used as a heat source.
- this air conditioner In this air conditioner, a constant amount of water is used as the heat source regardless of the flow rate of the refrigerant flowing in the heat source side heat exchanger, and the evaporation capacity in the heat source side heat exchange is controlled by controlling the amount of water. Can not control. However, in this air conditioner, the control range when controlling the evaporation capacity of the heat source side heat exchanger by the heat source side expansion valve is expanded, so that the heat source side heat exchanger can be controlled without controlling the amount of water. It is possible to secure a control range when controlling the evaporation capacity of the gas.
- An air conditioner according to a thirteenth aspect is the air conditioner according to any of the sixth to twelfth aspects, wherein the heat source side heat exchanger is a plate heat exchanger.
- a plate-type heat exchanger is used as the heat source side heat exchanger, and due to its structure, in order to prevent refrigeration oil from collecting in the heat source side heat exchanger, it is above the liquid level of the refrigerant. It is difficult to extract the refrigeration oil accumulated in the floating state near the coolant level.
- the refrigerating machine oil accumulates in the heat source side heat exchanger in a state of being mixed with the refrigerant, and the refrigerating machine oil accumulated in the heat source side heat exchanger is extracted together with the refrigerant from the lower force of the heat source side heat exchange. Therefore, it is easy to install an oil return circuit even when plate-type heat exchange is used.
- An air conditioner according to a fourteenth aspect of the present invention includes a refrigerant circuit and an oil return circuit.
- the refrigerant circuit includes a compression mechanism, a heat source side heat exchanger that is configured such that when the refrigerant functions as an evaporator, the refrigerant flows into the lower force and flows out from the upper side, and the heat source side expansion valve.
- the heat source side refrigerant circuit is composed of a plurality of user side refrigerant circuits connected to the user side heat exchanger and the user side expansion valve, and the heat source side heat exchanger is evaporated.
- the oil return circuit is connected to the lower part of the heat source side heat exchanger, and returns the refrigeration oil accumulated in the heat source side heat exchanger to the compression mechanism together with the refrigerant.
- the heat source side refrigerant circuit when functioning as an evaporator, the heat source side refrigerant circuit having a heat source side heat exchanger configured to allow the refrigerant to flow into the lower force and flow out from the upper side, and a plurality of use side refrigerants
- the heat source side heat exchanger functions as an evaporator as refrigeration oil and refrigerant used in the refrigerant circuit
- the refrigerant circuit is configured to be connected to the circuit.
- a combination of refrigerating machine oil and refrigerant is used in the heat exchanger on the heat source side and not separated into two layers.
- the refrigerating machine oil floats on the refrigerant level in the heat source side heat exchanger under the condition of the refrigerant evaporation temperature in the heat source side heat exchanger functioning as an evaporator. It does not accumulate in the heated state, but accumulates in the heat source side heat exchanger in a mixed state with the refrigerant.
- the refrigerating machine oil accumulated in the heat source side heat exchange is returned to the compression mechanism together with the refrigerant by an oil return circuit connected to the lower part of the heat source side heat exchange. For this reason, as in conventional air conditioners, the refrigerant level in the heat source side heat exchanger is maintained at a certain level or more in order to prevent refrigeration oil from accumulating in the heat source side heat exchanger. There is no need to do it.
- control is performed to reduce the evaporation capability of the heat source side heat exchanger by reducing the opening of the heat source side expansion valve in accordance with the air conditioning load of the plurality of use side refrigerant circuits.
- refrigeration oil does not accumulate in the heat source side heat exchange even if the refrigerant level in the heat source side heat exchange decreases, so the evaporation capacity of the heat source side heat exchange is expanded on the heat source side. It is possible to expand the control range when controlling by a valve.
- this air conditioner like the conventional air conditioner, a plurality of heat source side heat exchangers are provided to evaporate the heat source side heat exchange.
- the evaporation capacity can be reduced, or multiple heat source side Make a part of heat exchange ⁇ function as a condenser Since there is no need to control to reduce the evaporation capacity by offsetting the evaporation capacity of the heat source side heat exchanger that functions as an evaporator, a wide range of evaporation capacity can be controlled by a single heat source side heat exchanger. You will be able to get
- FIG. 1 is a schematic refrigerant circuit diagram of an air conditioner according to an embodiment of the present invention.
- FIG. 2 is a diagram showing the overall schematic structure of a heat source side heat exchanger.
- FIG. 3 is an enlarged view of a portion C in FIG. 2, and shows a schematic structure of the lower part of the heat source side heat exchanger.
- FIG. 4 is a schematic refrigerant circuit diagram for explaining the operation of the air-conditioning apparatus in a heating operation mode.
- FIG. 5 is a schematic refrigerant circuit diagram for explaining the operation of the air-conditioning apparatus in a cooling operation mode.
- FIG. 6 is a schematic refrigerant circuit diagram for explaining the operation of the air-conditioning apparatus in the simultaneous heating and cooling operation mode (evaporation load).
- FIG. 7 is a schematic refrigerant circuit diagram for explaining the operation of the air-conditioning apparatus in the simultaneous heating and cooling operation mode (condensing load).
- FIG. 8 is a schematic refrigerant circuit diagram of an air-conditioning apparatus according to Modification 1.
- FIG. 9 is a schematic refrigerant circuit diagram for explaining the operation of the air-conditioning apparatus of Modification 1 in the heating operation mode.
- FIG. 10 is a schematic refrigerant circuit diagram for explaining the operation of the air-conditioning apparatus of Modification 1 in the cooling operation mode.
- FIG. 11 is a schematic refrigerant circuit diagram of an air-conditioning apparatus according to Modification 2.
- FIG. 12 is a schematic refrigerant circuit diagram of an air-conditioning apparatus according to Modification 3.
- FIG. 13 is a schematic refrigerant circuit diagram of an air-conditioning apparatus according to Modification 4.
- FIG. 14 is a schematic refrigerant circuit diagram of an air-conditioning apparatus according to Modification 4.
- FIG. 15 is a schematic refrigerant circuit diagram of an air-conditioning apparatus according to Modification 4.
- FIG. 16 is a schematic refrigerant circuit diagram of an air-conditioning apparatus according to Modification 4.
- FIG. 1 is a schematic refrigerant circuit diagram of an air-conditioning apparatus 1 according to an embodiment of the present invention.
- the air conditioner 1 is an apparatus used for indoor air conditioning such as a building by performing a vapor compression refrigeration cycle operation.
- the air conditioner 1 mainly includes one heat source unit 2, a plurality (three in this embodiment) of usage units 3, 4, 5, and connection units connected to the usage units 3, 4, 5. 6, 7, 8, and refrigerant connection pipes 9, 10, 11 connecting the heat source unit 2 and the utilization units 3, 4, 5 via the connection units 6, 7, 8, for example, an air conditioner Use units 3, 4, and 5 can be used, such as performing cooling operations for spaces and heating operations for other air-conditioned spaces. It is configured to enable simultaneous cooling and heating according to the requirements of the indoor air-conditioning space installed. That is, the vapor compression refrigerant circuit 12 of the air conditioner 1 of the present embodiment includes a heat source unit 2, utilization units 3, 4, 5, connection units 6, 7, 8, and refrigerant communication pipes 9, 10, 11 is connected.
- the refrigerant circuit 12 of the air conditioner 1 uses a combination of refrigerating machine oil and refrigerant that is not separated into two layers within a temperature range of 20 ° C or lower.
- a combination of such a refrigerant and refrigerating machine oil for example, there is a combination of R410A and an ether oil such as polyvinyl ether (PVE).
- PVE polyvinyl ether
- the combination of the refrigerating machine oil and the refrigerant that is not separated into two layers within the temperature range of ⁇ 20 ° C. or lower is as follows.
- the maximum value of the evaporation temperature of the refrigerant when operating the heat source side heat exchange 23 (described later) of the heat source unit 2 as an evaporator is 30 ° C
- at least the maximum value of this evaporation temperature in the temperature range of 30 ° C or lower, the refrigerant oil and the refrigerant accumulated in the heat source side heat exchanger 23 are not separated into two layers, so that the refrigerant is supplied from the lower part of the heat source side heat exchange.
- the refrigeration oil can be extracted and returned to the compression mechanism 21 (described later) of the heat source unit 2.
- the heat source side heat exchange 23 (described later) of the heat source unit 2 functions as an evaporator, in a temperature range below the minimum value of the evaporation temperature
- the lower force of the heat source side heat exchange also draws out the refrigerating machine oil together with the refrigerant, and the compression mechanism of the heat source unit 2 21 This is because it is desirable to be able to return to (described later).
- the minimum evaporating temperature is 5 ° C when water is used as the heat source of the heat source side heat exchanger 23, and when air is used as the heat source of the heat source side heat exchanger 23—
- the temperature is 15 ° C., and 20 ° C. when brine (for example, containing 40 to 50 wt% ethylene glycol) is used as the heat source of the heat source side heat exchanger 23.
- Usage units 3, 4, and 5 are installed in the ceiling of a building or the like by suspending or hanging, or hanging on the wall of the building. Usage units 3, 4, and 5 are connected to refrigerant communication pipe 9 , 10, 11 and connection units 6, 7, 8 are connected to the heat source unit 2 and constitute a part of the refrigerant circuit 12.
- the usage unit 3 mainly constitutes a part of the refrigerant circuit 12, and includes a usage-side refrigerant circuit 12a (in the usage units 4 and 5, usage-side refrigerant circuits 12b and 12c, respectively).
- the use side refrigerant circuit 12a mainly includes a use side expansion valve 31 and a use side heat exchange 32.
- the use side expansion valve 31 is an electric expansion valve connected to the liquid side of the use side heat exchanger 32 in order to adjust the flow rate of the refrigerant flowing in the use side refrigerant circuit 12a. is there.
- the use side heat exchanger 32 is a cross-fin type fin 'and' tube type heat exchanger composed of heat transfer tubes and a large number of fins, and exchanges heat between the refrigerant and indoor air. It is a device for performing.
- the utilization unit 3 includes a blower fan (not shown) for supplying indoor air as supply air after sucking indoor air into the unit and exchanging heat. It is possible to exchange heat with the refrigerant flowing through the use side heat exchanger 32.
- the utilization unit 3 is provided with various sensors.
- a liquid side temperature sensor 33 for detecting the temperature of the liquid refrigerant is provided on the liquid side of the use side heat exchanger 32, and a gas side temperature for detecting the temperature of the gas refrigerant is provided on the gas side of the use side heat exchanger 32.
- Sensor 34 is provided.
- the utilization unit 3 is provided with an RA intake temperature sensor 35 for detecting the temperature of indoor air sucked into the unit.
- the usage unit 3 includes a usage-side control unit 36 that controls the operation of each unit constituting the usage unit 3.
- the use-side control unit 36 includes a microcomputer and a memory provided for controlling the use unit 3, and exchanges control signals and the like with a remote controller (not shown). Control signals etc. can be exchanged with the heat source unit 2.
- the heat source unit 2 is installed on the roof of a building, etc.
- the usage units 3, 4, and 5 are connected to each other, and a refrigerant circuit 12 is configured between the usage units 3, 4, and 5.
- the heat source unit 2 mainly constitutes a part of the refrigerant circuit 12, and includes a heat source side refrigerant circuit 12d.
- the heat source side refrigerant circuit 10d mainly includes a compression mechanism 21, a first switching mechanism 22, a heat source side heat exchanger 23, a heat source side expansion valve 24, a receiver 25, a second switching mechanism 26, Side closing valve 27, high pressure gas side closing valve 28, low pressure gas side closing valve 29, first oil return circuit 101, pressurizing circuit 111, cooler 121, and cooling circuit 122.
- the compression mechanism 21 mainly includes a compressor 21a, an oil separator 21b connected to the discharge side of the compressor 21a, and a second oil return circuit 2 that connects the oil separator 21b and the suction pipe 21c of the compressor 21a 2 Id.
- the compressor 21a is a positive displacement compressor capable of varying the operating capacity by inverter control.
- the oil separator 21b is a container for separating the refrigerating machine oil accompanying the high-pressure gas refrigerant compressed and discharged in the compressor 21a.
- the second oil return circuit 21d is a circuit for returning the refrigeration oil separated in the oil separator 21b to the compressor 21a.
- the second oil return circuit 21d mainly includes an oil return pipe 21e that connects the oil separator 21b and the suction pipe 21c of the compressor 21a, and a high pressure separated in the oil separator 21b that is connected to the oil return pipe 21e. And a capillary tube 21f for reducing the pressure of the refrigerating machine oil.
- the capillary tube 21f is a thin tube that depressurizes the high-pressure refrigeration oil separated in the oil separator 21b to the refrigerant pressure on the suction side of the compressor 21a.
- the compression mechanism 21 has only one compressor 21a as a compressor, but is not limited to this, and two or more compressors are connected in parallel according to the number of connected units. It may have been done.
- the first shelf structure 22 connects the discharge side of the compression mechanism 21 and the gas side of the heat source side heat exchanger 23 when the heat source side heat exchanger 23 functions as a condenser (hereinafter referred to as a condensation operation state).
- a condensation operation state When the heat source side heat exchanger 23 functions as an evaporator (hereinafter referred to as the evaporation operation state), the heat source side heat exchanger 23 is connected to the suction side of the compression mechanism 21 and the gas side of the heat source side heat exchanger 23.
- the first switching mechanism 22 connects the first port 22a and the second port 22b, and connects the third port 22c and the fourth port 22d (corresponding to the condensed operation state, (Refer to the solid line of the first structure 22 in Fig. 1), or connect the second port 22b and the third port 22c, and connect the first port 22c and the fourth port 22d (corresponding to the evaporation operation state) (See the broken line in the first structure 22 in FIG. 1).
- the heat source side heat exchanger 23 is a heat exchanger that can function as a refrigerant evaporator and a refrigerant condenser. In the present embodiment, plate heat exchange is performed in which heat is exchanged with the refrigerant using water as a heat source. It is a vessel.
- the gas side of the heat source side heat exchanger 23 is connected to the second port 22b of the first switching mechanism 22, and the liquid side is connected to the heat source side expansion valve 24.
- the heat source side heat exchanger 23 is formed by stacking a plurality of plate members 23a formed by a press cage or the like via a packing (not shown).
- a plurality of channels 23b and 23c extending in the vertical direction are formed in the plurality of channels, and refrigerant and water flow alternately in the channels 23b and 23c (specifically, the refrigerant flows in the channel 23b). Heat is exchanged by water flowing in the flow path 23c (see arrows A and B in FIG. 2).
- the plurality of flow paths 23b are in communication with each other at the upper end portion and the lower end portion thereof, and are connected to the gas side nozzle 23d and the liquid side nozzle 23e provided at the upper and lower portions of the heat source side heat exchange. ing.
- the gas side nozzle 23d is connected to the first structure 22, and the liquid side nozzle 23e is connected to the heat source side expansion valve 24.
- the heat source side heat exchanger 23 functions as an evaporator
- the refrigerant flows in from the liquid side nozzle 23e (ie, the lower side) and out of the gas side nozzle 23d (ie, the upper side).
- the heat source side heat exchanger 23 functions as a condenser
- the plurality of flow paths 23c are connected to each other at the upper end and the lower end, and are connected to the water inlet nozzle 23f and the water outlet nozzle 23g provided at the upper and lower portions of the heat source side heat exchanger 23. Has been.
- the feed water CWS flows from the water inlet nozzle 23f of the heat source side heat exchanger 23 through the water pipe (not shown) of the cold water tower equipment and boiler equipment power installed outside the air conditioner 1. After exchanging heat with the refrigerant, it flows out from the water outlet nozzle 23g and returns to the chilled water tower equipment and boiler equipment as discharged CWR.
- a certain amount of water supplied from the cold water tower equipment or boiler equipment is supplied regardless of the flow rate of the refrigerant flowing in the heat source side heat exchanger 23.
- the heat source side expansion valve 24 adjusts the flow rate of the refrigerant flowing between the heat source side heat exchanger 23 and the use side refrigerant circuits 12a, 12b, 12c via the liquid refrigerant communication pipe 9 according to the present embodiment.
- This is an electric expansion valve that can be connected to the liquid side of the heat source side heat exchange.
- the receiver 25 is a container for temporarily storing the refrigerant flowing between the heat source side heat exchanger 23 and the use side refrigerant circuits 12a, 12b, and 12c. In the present embodiment, the receiver 25 is connected between the heat source side expansion valve 24 and the cooler 121.
- the second Kiriura structure 26 is used when the heat source unit 2 is used as a heat source unit for a cooling and heating simultaneous machine (see FIGS. 4 to 7), and a high-pressure gas refrigerant is sent to the use-side refrigerant circuits 12a, 12b, and 12c. (Hereinafter referred to as the heating load required operation state)
- the heat source unit 2 is used as a heat source unit for a cooling / heating switching machine (deformation) (Refer to Example 1, Figs.
- cooling operation state when switching between cooling and heating connects the high pressure gas side shut-off valve 28 and the suction side of the compression mechanism 21 to each other.
- it is a four-way switching valve capable of switching the refrigerant flow path in the heat source side refrigerant circuit 12d, and its first port 26a is connected to the discharge side of the compression mechanism 21, and its second port 26b is It is connected to the suction side of the compression mechanism 21 via a capillary tube 92.
- Its third port 26c is connected to the intake side of the compression mechanism 21, the fourth port 2 6d is connected to the high-pressure gas closing valve 28.
- the second mechanism 26 connects the first port 26a and the second port 26b, and also connects the third port 26c and the fourth port 26d (corresponding to the cooling operation state during cooling / heating switching). 1) (Refer to the solid line of the second switching mechanism 26 in FIG. 1), connect the second port 26b and the third port 26c, and connect the first port 26a and the fourth port 26d (heating load demand operation) It is possible to perform switching that corresponds to the state (see the broken line of the second switching mechanism 26 in FIG. 1).
- the liquid side shut-off valve 27, the high-pressure gas side shut-off valve 28, and the low-pressure gas side shut-off valve 29 are provided at a connection port with an external device / pipe (specifically, the refrigerant communication pipes 9, 10 and 11). Valve.
- the liquid side closing valve 27 is connected to the cooler 121.
- the high-pressure gas side closing valve 28 is connected to the fourth port 26 d of the second structure 26.
- the low pressure gas side closing valve 29 is connected to the suction side of the compression mechanism 21.
- the first oil return circuit 101 returns the refrigerating machine oil accumulated in the heat source side heat exchanger 23 together with the refrigerant to the compression mechanism 21 when the evaporation operation state is performed, that is, when the heat source side heat exchanger 23 functions as an evaporator. Circuit.
- the first oil return circuit 101 mainly includes an oil return pipe 101a connecting the lower part of the heat source side heat exchanger 23 and the compression mechanism 21, an on-off valve 101b connected to the oil return pipe 101a, and a check valve 101c. And a cylindrical tube lOld.
- the oil return pipe 101a is provided at one end so that the lower force of the heat source side heat exchange can also extract the refrigerating machine oil together with the refrigerant. In this embodiment, as shown in FIG.
- the heat source side heat exchange is performed.
- This is a pipe that extends to the inside of the flow path 23b through which the refrigerant of the heat source side heat exchanger 23 flows through the pipe of the liquid side nozzle 23e provided in the lower part of the vessel 23.
- a communication hole 23h is provided in each plate member 23a (the same applies to the plurality of flow paths 23c).
- the oil return pipe 101a may be provided so as to penetrate the plurality of flow paths 23b (see the oil return pipe 101a indicated by the broken line in FIG. 3).
- the other end of the oil return pipe 101a is connected to the suction side of the compression mechanism 21 in this embodiment.
- the on-off valve 101b is connected so that the first oil return circuit 101 can be used as necessary, and is an electromagnetic valve capable of circulating and blocking refrigerant and refrigerating machine oil.
- the check valve 101c is a valve that allows only the lower force of the heat source side heat exchanger 23 and the lower force of the heat source side heat exchanger 23 to flow in the oil return pipe 101a toward the suction side of the compression mechanism 21.
- the capillary tube 101d is a thin tube that depressurizes the refrigerant and refrigerating machine oil extracted from the lower part of the heat source side heat exchanger 23 to the refrigerant pressure on the suction side of the compression mechanism 21.
- the pressurizing circuit 111 converts the high-pressure gas refrigerant compressed in the compression mechanism 21 into the heat source side heat exchanger 23 in the condensing operation state, that is, when the heat source side heat exchanger 23 functions as a condenser. After being condensed in the heat source and decompressed in the heat source side expansion valve 24, the use side refrigerant circuit This circuit joins the refrigerant sent to 12a, 12b, and 12c.
- the pressurizing circuit 111 mainly includes a pressurizing pipe 111a that connects the discharge side of the compression mechanism 21 and the downstream side of the heat source side expansion valve 24 (that is, between the heat source side expansion valve 24 and the liquid side closing valve 27), It has an open / close valve 11 lb connected to the pressurizing pipe 111a, a check valve 111c, and a capillary tube 11 Id.
- the calo pressure pipe 11 la is connected at one end between the outlet of the oil separator 21b of the compression mechanism 21 and the first ports 22a and 26a of the first and second structures 22 and 26.
- the other end of the pressurizing pipe 111a is connected between the heat source side expansion valve 24 and the receiver 25 in the present embodiment.
- the on-off valve 11 lb is connected so that the pressurizing circuit 111 can be used as necessary, and is an electromagnetic valve capable of circulating and blocking the refrigerant.
- the check valve 111c is a valve that only allows the refrigerant to flow in the pressurizing pipe 11la from the discharge side of the compression mechanism 21 toward the downstream side of the heat source side expansion valve 24.
- the capillary tube 11 Id is a thin tube that depressurizes the refrigerant extracted from the discharge side of the compression mechanism 21 to the refrigerant pressure downstream of the heat source side expansion valve 24.
- the cooler 121 In the condensing operation state, that is, when the heat source side heat exchanger 23 functions as a condenser, the cooler 121 is condensed in the heat source side heat exchange and then depressurized in the heat source side expansion valve 24 to be used side refrigerant circuit
- This is a heat exchanger that cools the refrigerant sent to 12a, 12b, and 12c.
- the cooler 121 is connected between the receiver 25 and the liquid side closing valve 27.
- the pressurization pipe 111a is connected between the heat source side expansion valve 24 and the cooler 121 so that the high-pressure gas refrigerant merges with the refrigerant depressurized in the heat source side expansion valve 24. It is connected to the.
- a double-pipe heat exchanger can be used as the cooler 121.
- the cooling circuit 122 When the cooling circuit 122 is in a condensing operation state, that is, when the heat source side heat exchanger 23 functions as a condenser, a part of the refrigerant sent from the heat source side heat exchange to the use side refrigerant circuits 12a, 12b, 12c is used as the heat source. Branched from the side refrigerant circuit 12d, introduced into the cooler 121, condensed in the heat source side heat exchanger 23, depressurized in the heat source side expansion valve 24, and sent to the usage side refrigerant circuits 12a, 12b, 12c This is a circuit connected to the heat source side refrigerant circuit 12d so as to return to the suction side of the compression mechanism 21 after the refrigerant to be cooled.
- the cooling circuit 122 mainly cools a part of the refrigerant sent from the heat source side heat exchanger 23 to the use side refrigerant circuits 12a, 12b, and 12c. And a cooling circuit side expansion valve 122b connected to the introduction pipe 122a, and a lead-out pipe 122c for returning the refrigerant that has passed through the cooler 121 to the suction side of the compression mechanism 21.
- one end of the introduction pipe 122 a is connected between the receiver 25 and the cooler 121.
- the other end of the introduction pipe 122a is connected to the inlet of the cooler 121 on the cooling circuit 122 side in this embodiment.
- the cooling circuit side expansion valve 122b is connected so that the cooling circuit 122 can be used as necessary, and the electric circuit capable of adjusting the flow rate of the refrigerant flowing through the cooling circuit 122. It is an expansion valve.
- one end of the outlet tube 122c is connected to the outlet of the cooler 121 on the cooling circuit 122 side.
- the other end of the outlet pipe 122c is connected to the suction side of the compression mechanism 21.
- the heat source unit 2 is provided with various sensors. Specifically, the heat source unit 2 includes a suction pressure sensor 93 that detects a suction pressure of the compression mechanism 21, a discharge pressure sensor 94 that detects a discharge pressure of the compression mechanism 21, and a discharge side of the compression mechanism 21. A discharge temperature sensor 95 for detecting the discharge temperature of the refrigerant and a cooling circuit outlet temperature sensor 96 for detecting the temperature of the refrigerant flowing through the outlet pipe 122c of the cooling circuit 122 are provided. Further, the heat source unit 2 includes a heat source side control unit 97 that controls the operation of each part constituting the heat source unit 2. The heat source side control unit 97 has a microcomputer memory provided for controlling the heat source unit 2, and uses side control units 36, 46, 46 of the usage units 3, 4, 5. Control signal etc. can be exchanged with 56! /.
- Connection units 6, 7, and 8 are installed indoors, such as in buildings, along with usage units 3, 4, and 5.
- the connection units 6, 7, 8 are interposed between the use units 3, 4, 5 and the heat source unit 2 together with the refrigerant communication pipes 9, 10, 11, and constitute a part of the refrigerant circuit 12,
- the connection units 6, 7, 8 are interposed between the use units 3, 4, 5 and the heat source unit 2 together with the refrigerant communication pipes 9, 10, 11, and constitute a part of the refrigerant circuit 12, The
- connection unit 6 and the connection units 7 and 8 have the same configuration, only the configuration of the connection unit 6 will be described here, and the configuration of the connection units 7 and 8 will be described respectively.
- Symbols in the 70's or 80's are attached instead of the symbols in the 60's indicating each part of 6 and the explanation of each part is omitted.
- the connection unit 6 mainly constitutes a part of the refrigerant circuit 12 mainly on the connection side.
- the refrigerant circuit 12e (in the connection units 7 and 8, connection side refrigerant circuits 12f and 12g, respectively) is provided.
- the connection-side refrigerant circuit 12e mainly includes a liquid connection pipe 61, a gas connection pipe 62, a high pressure gas on / off valve 66, and a low pressure gas on / off valve 67.
- the liquid connection pipe 61 connects the liquid refrigerant communication pipe 9 and the use side expansion valve 31 of the use side refrigerant circuit 12a.
- the gas connection pipe 62 includes a high pressure gas connection pipe 63 connected to the high pressure gas refrigerant communication pipe 10, a low pressure gas connection pipe 64 connected to the low pressure gas refrigerant communication pipe 11, and a high pressure gas connection pipe 63. It has a confluence gas connection pipe 65 that joins the pipe 64 and has one stroke.
- the combined gas connection pipe 65 is connected to the gas side of the use side heat exchange of the use side refrigerant circuit 12a.
- the high-pressure gas on-off valve 66 is connected to the high-pressure gas connection pipe 63 and is an electromagnetic valve capable of circulating and blocking the refrigerant.
- the low-pressure gas on-off valve 67 is connected to the low-pressure gas connection pipe 64 and is an electromagnetic valve capable of circulating and blocking the refrigerant.
- the connection unit 6 closes the high-pressure gas on-off valve 66 and opens the low-pressure gas on-off valve 67, and then connects the liquid through the liquid refrigerant communication pipe 9.
- connection pipe 61 The refrigerant flowing into the connection pipe 61 is sent to the use-side expansion valve 31 of the use-side refrigerant circuit 12a, decompressed by the use-side expansion valve 31, and evaporated in the use-side heat exchange, and then the combined gas connection pipe 65 and the low-pressure gas It can function to return to the low-pressure gas refrigerant communication pipe 11 through the connection pipe 64.
- the connection unit 6 closes the low pressure gas on / off valve 67 and opens the high pressure gas on / off valve 66, and opens the high pressure gas through the high pressure gas refrigerant communication pipe 10.
- connection unit 6 includes a connection-side control unit 68 that controls the operation of each unit constituting the connection unit 6.
- the connection side control unit 68 includes a microcomputer and a memory provided for controlling the connection unit 6, and exchanges control signals and the like with the use side control unit 36 of the use unit 3. Now that you can do that!
- the use side refrigerant circuits 12a, 12b, and 12c, the heat source side refrigerant circuit 12d, the refrigerant communication pipes 9, 10, and 11 and the connection side refrigerant circuits 12e, 12f, and 12g are connected, and the air Harmony The refrigerant circuit 12 of the apparatus 1 is configured.
- the air conditioner 1 of the present embodiment for example, it is possible to perform a so-called cooling / heating simultaneous operation such that the usage units 3 and 4 perform a cooling operation while the usage unit 5 performs a heating operation. Yes.
- the heat source side heat exchanger 23 when the heat source side heat exchanger 23 is caused to function as an evaporator, the first oil return circuit 101 is used, whereby the heat source side heat exchanger 23
- the pressurization circuit 111 and the cooler 121 are used so that the heat source side heat exchanger 23
- the control range when the condensing capacity is controlled by the heat source side expansion valve 24 has been expanded, and a wide control range of the condensing capacity can be obtained by the single heat source side heat exchanger 23.
- the operation mode of the air conditioner 1 of the present embodiment includes a heating operation mode in which all the usage units 3, 4, and 5 are heated according to the air conditioning load of each usage unit 3, 4, and 5, and a usage unit 3 , 4 and 5 can be divided into a cooling operation mode in which the cooling operation is performed and a cooling and heating simultaneous operation mode in which some of the usage units 3, 4, and 5 perform the cooling operation while the other usage units perform the heating operation. it can.
- the operation mode can be divided into the operation mode (condensation operation state) when the heat source side heat exchanger 23 of the heat source unit 2 is operated as a condenser.
- the refrigerant circuit 12 of the air conditioner 1 It is configured as shown in FIG. 4 (refer to the arrow attached to the refrigerant circuit 12 in FIG. 4 for the refrigerant flow).
- the first switching mechanism 22 is switched to the evaporation operation state (the state indicated by the broken line of the first switching mechanism 22 in FIG. 4), and the second switching mechanism By switching 26 to the heating load required operation state (the state indicated by the broken line of the second switching mechanism 26 in Fig.
- the heat source side heat exchange 23 functions as an evaporator and the high pressure gas refrigerant communication
- the high-pressure gas refrigerant compressed and discharged by the compression mechanism 21 can be supplied to the utilization units 3, 4, and 5 through the pipe 10! /.
- the opening degree of the heat source side expansion valve 24 is adjusted so as to depressurize the refrigerant.
- the on-off valve 111b of the pressurizing circuit 111 and the cooling circuit side expansion valve 122b of the cooling circuit 122 are closed, and a high-pressure gas refrigerant is combined with the refrigerant flowing between the heat source side expansion valve 24 and the receiver 25.
- connection units 6, 7, and 8 use side heat of usage units 3, 4, and 5 by closing low pressure gas on / off valves 67, 77, and 87 and opening high pressure gas on / off valves 66, 76, and 86
- the exchangers 32, 42 and 52 are in a state of functioning as a condenser.
- the usage side expansion valves 31, 41, and 51 are, for example, the degree of supercooling of the usage side heat exchangers 32, 42, and 52 (specifically, the liquid side temperature sensor 33, Opening according to the heating load of each usage unit, such as adjusting the opening based on the temperature difference between the refrigerant temperature detected by 43 and 53 and the refrigerant temperature detected by gas side temperature sensors 34, 44 and 54) The degree is adjusted.
- the high-pressure gas refrigerant compressed and discharged by the compressor 21a of the compression mechanism 21 is mostly contained in the high-pressure gas refrigerant in the oil separator 21b. Separated and sent to Second Unit 26.
- the refrigerating machine oil separated in the oil separator 21b is returned to the suction side of the compressor 21a through the second oil return circuit 21d.
- the high-pressure gas refrigerant sent to the second structure 26 is sent to the high-pressure gas refrigerant communication pipe 10 through the first port 26a and the fourth port 26d of the second structure 26 and the high-pressure gas side closing valve 28.
- the high-pressure gas refrigerant sent to the high-pressure gas refrigerant communication pipe 10 is branched into three and sent to the high-pressure gas connection pipes 63, 73, 83 of the connection units 6, 7, 8.
- Connection unit 6 The high-pressure gas refrigerant sent to the high-pressure gas connection pipes 63, 73, 83 of ⁇ , 7, 8 passes through the high-pressure gas on-off valves 66, 76, 86 and the merged gas connection pipes 65, 75, 85. , 4, 5 sent to IJ side heat exchange ⁇ 32, 42, 52.
- the high-pressure gas refrigerant sent to the use-side heat exchangers 32, 42, 52 is heated with indoor air in the use-side heat exchangers 32, 42, 52 of the use units 3, 4, 5 It is condensed by exchanging. On the other hand, indoor air is heated and supplied indoors.
- the refrigerant condensed in the use side heat exchangers 32, 42, 52 passes through the use side expansion valves 31, 41, 51 and then is sent to the liquid connection pipes 61, 71, 81 of the connection units 6, 7, 8 .
- the refrigerant sent to the liquid connection pipes 61, 71, 81 is sent to the liquid refrigerant communication pipe 9 to join.
- the refrigerant sent to the liquid refrigerant communication pipe 9 and joined together is sent to the receiver 25 through the liquid side closing valve 27 and the cooler 121 of the heat source unit 2.
- the refrigerant sent to the receiver 25 is temporarily stored in the receiver 25 and then decompressed by the heat source side expansion valve 24.
- the refrigerant decompressed by the heat source side expansion valve 24 is evaporated by exchanging heat with water as a heat source in the heat source side heat exchanger 23 to become a low-pressure gas refrigerant. Sent.
- the low-pressure gas refrigerant sent to the first mechanism 22 is returned to the suction side of the compression mechanism 21 through the second port 22b and the third port 22c of the first switching mechanism 22. In this way, the operation in the heating operation mode is performed.
- the heating load of each of the usage units 3, 4, and 5 may be very small.
- the refrigerant evaporation capacity in the heat source side heat exchange 23 of the heat source unit 2 is reduced, and the heating load of the entire usage units 3, 4, 5 (that is, the usage side heat exchangers 32, 42, Must be balanced with a condensing load of 52).
- control is performed to reduce the evaporation amount of the refrigerant in the heat source side heat exchange by controlling the opening degree of the heat source side expansion valve 24 to be small.
- the control for reducing the opening degree of the heat source side expansion valve 24 is performed, the liquid level of the refrigerant in the heat source side heat exchanger is lowered.
- the heat exchange is configured such that the refrigerant flows in both the lower force and the upper force (see FIGS. 2 and 2). (Refer to (3)), it becomes difficult for the refrigeration oil to be discharged together with the evaporated refrigerant. It tends to occur.
- the combined refrigerating machine oil and In addition to using the refrigerant that is, when the heat source side heat exchanger functions as an evaporator, use the combined refrigerating machine oil and refrigerant without being separated into two layers in the heat source side heat exchanger).
- An oil return circuit 101 is provided.
- the on-off valve 101b of the first oil return circuit 101 is opened in the heating operation mode (that is, when the first switching mechanism 22 is in the evaporation operation state), and passes through the oil return pipe 101a.
- Refrigerating machine oil can be extracted from the heat source side heat exchanger 23 together with the refrigerant from the lower part of the heat source side heat exchanger 23 and returned to the compression mechanism 21.
- the on-off valve 101b is returned to the compression mechanism 21 when a part of the refrigerant condensed in the heat source side heat exchanger 23 is opened.
- the amount of refrigerant sent to the use-side refrigerant circuits 12a, 12b, and 12c is reduced, so that the first switching mechanism 22 is closed when the first switching mechanism 22 is in the condensing operation state. It is desirable to open it when it is in the evaporative operation state.
- the liquid level of the refrigerant in the heat source side heat exchanger is reduced by performing control to reduce the opening degree of the heat source side expansion valve 24, It may be opened only when the refrigeration oil is accompanied by the evaporated refrigerant and is not easily discharged.
- the heat source side expansion valve 24 is not more than a predetermined opening.
- This predetermined opening degree is the opening degree of the heat source side expansion valve 24 in which the liquid level of the cooling medium in the heat source side heat exchanger 23 is lowered and the refrigerant oil is not easily discharged together with the evaporated refrigerant. Is determined experimentally and is determined based on the opening found experimentally. [0048] ⁇ Cooling operation mode>
- the refrigerant circuit 12 of the air conditioner 1 is configured as shown in FIG. 5 (the refrigerant flow is attached to the refrigerant circuit 12 of FIG. 5). (See the arrow marked.)
- the first switching mechanism 22 is switched to the condensation operation state (the state indicated by the solid line of the first switching mechanism 22 in FIG. 5), thereby Heat exchange is functioning as a condenser.
- the heat source side expansion valve 24 is in an opened state.
- connection units 6, 7, and 8 use side heat exchange of usage units 3, 4, and 5 by closing high pressure gas on / off valves 66, 76, and 86 and opening low pressure gas on / off valves 6 7, 77, and 87
- Units 32, 42, and 52 function as evaporators, and use side heat exchange 32, 42, and 52 of usage units 3, 4, and 5 and the suction side of compression mechanism 21 of heat source unit 2 communicate with low-pressure gas refrigerant.
- pipe 11 connected via pipe 11.
- the usage side expansion valves 31, 41, and 51 are, for example, the degree of superheat of the usage side heat exchangers 32, 42, and 52 (specifically, the liquid side temperature sensors 33, 43, The opening degree is adjusted according to the cooling load of each usage unit, such as the opening degree is adjusted based on the refrigerant temperature detected by 53 and the refrigerant temperature detected by the gas side temperature sensors 34, 44, 54). Speak.
- the high-pressure gas refrigerant compressed and discharged by the compressor 21a of the compression mechanism 21 is supplied to the high-pressure gas refrigerant in the oil separator 21b. Most of them are separated and sent to the first switching mechanism 22.
- the refrigerating machine oil separated in the oil separator 21b is returned to the suction side of the compressor 21a through the second oil return circuit 21d.
- the high-pressure gas refrigerant sent to the first switching mechanism 22 is sent to the heat source side heat exchanger 23 through the first port 22a and the second port 22b of the first switching mechanism 22.
- the high-pressure gas refrigerant sent to the heat source side heat exchanger 23 is condensed by exchanging heat with water as the heat source in the heat source side heat exchanger 23.
- the refrigerant condensed in the heat source side heat exchange 23 passes through the heat source side expansion valve 24, and then the high pressure gas refrigerant compressed and discharged by the compression mechanism 21 through the pressurizing circuit 111 joins (details will be described later).
- Sent to No. 25 The refrigerant sent to the receiver 25 is temporarily stored in the receiver 25 and then sent to the cooler 121. Then, the refrigerant sent to the cooler 121 is cooled by exchanging heat with the refrigerant flowing through the cooling circuit 122 (details will be described later). Then, the refrigerant cooled in the cooler 121 is sent to the liquid refrigerant communication pipe 9 through the liquid side closing valve 27.
- the refrigerant sent to the liquid refrigerant communication pipe 9 is branched into three and sent to the liquid connection pipes 61, 71, 81 of the connection units 6, 7, 8 respectively. Then, the refrigerant sent to the liquid connection pipes 61, 71, 81 of the connection units 6, 7, 8 is sent to the use side expansion valves 31, 41, 51 of the use units 3, 4, 5.
- the refrigerant sent to the use side expansion valves 31, 41, 51 is depressurized by the use side expansion valves 31, 41, 51, and then exchanges heat with indoor air in the use side heat exchangers 32, 42, 52. Is evaporated into a low-pressure gas refrigerant. On the other hand, indoor air is cooled and supplied indoors. Then, the low-pressure gas refrigerant is sent to the merged gas connection pipes 65, 75, 85 of the connection units 6, 7, 8.
- the low-pressure gas refrigerant sent to the merged gas connection pipes 65, 75, 85 passes through the low-pressure gas on / off valves 67, 77, 87 and the low-pressure gas connection pipes 64, 74, 84 to the low-pressure gas refrigerant communication pipe 11. Sent to join.
- the low-pressure gas refrigerant sent to the low-pressure gas refrigerant communication pipe 11 and joined together is returned to the suction side of the compression mechanism 21 through the low-pressure gas side shut-off valve 29. In this way, the operation in the cooling operation mode is performed.
- each utilization unit 3, 4, and 5 may become very small.
- the refrigerant condensing capacity in the heat source side heat exchange 23 of the heat source unit 2 is reduced, and the cooling load (that is, the use side heat exchangers 32, 42, Must be balanced with an evaporation load of 52). Therefore, control is performed to reduce the amount of refrigerant condensed in the heat source side heat exchanger 23 by performing control to reduce the opening degree of the heat source side expansion valve 24.
- the opening of the heat source side expansion valve 24 By controlling the opening of the heat source side expansion valve 24 in this way, the amount of liquid refrigerant that accumulates in the heat source side heat exchanger increases! ] By reducing the effective heat transfer area, the condensation capacity is reduced.
- the high-pressure gas refrigerant compressed and discharged by the compression mechanism 21 is decompressed by the heat source side expansion valve 24 and used side refrigerant circuits 12a and 12b.
- 12c is provided with a pressurizing circuit 111 that joins the refrigerant sent to 12c.
- the on-off valve 111b of the pressurizing circuit 111 is opened in the cooling operation mode (that is, when the first switching mechanism 22 is in the condensing operation state), and is compressed through the pressurizing pipe 111a.
- the discharge side force can also be joined to the downstream side of the heat source side expansion valve 24.
- the high pressure gas refrigerant is joined to the downstream side of the heat source side expansion valve 24 through the pressurization circuit 111, thereby The pressure of the downstream refrigerant can be increased.
- the high-pressure gas refrigerant is merged, whereby the refrigerant sent to the use-side refrigerant circuits 12a, 12b, 12c.
- the cooler 121 is further provided on the downstream side of the heat source side expansion valve 24.
- the high pressure gas refrigerant is joined to the downstream side of the heat source side expansion valve 24 through the pressurization circuit 111 to thereby control the heat source side expansion valve 24.
- the refrigerant that is depressurized by the heat source side expansion valve 24 and sent to the use side refrigerant circuits 12a, 12b, 12c is cooled by the cooler 121.
- the gas refrigerant can be condensed, and it is not necessary to send a gas-liquid two-phase flow refrigerant having a large gas fraction to the use-side refrigerant circuits 12a, 12b, and 12c.
- the pressurizing pipe 111a is connected between the heat source side expansion valve 24 and the receiver 25, so that the refrigerant on the downstream side of the heat source side expansion valve 24 has a high pressure.
- Gas refrigerant merges and high-pressure gas refrigerant The refrigerant that has been merged and whose temperature has risen is cooled by the cooler 121.
- the cooling circuit 122 is provided, and a part of the refrigerant sent from the heat source side heat exchanger 23 to the use side refrigerant circuits 12a, 12b, 12c. Is reduced to a refrigerant pressure that can be returned to the suction side of the compression mechanism 21, and this refrigerant is used as a cooling source for the cooler 121. Therefore, the refrigerant is reduced in pressure at the heat source side expansion valve 24 and used on the refrigerant circuits 12a, 12b.
- a cooling source having a temperature sufficiently lower than the temperature of the refrigerant sent to 12c can be obtained. For this reason, it is possible to cool the refrigerant, which is decompressed in the heat source side expansion valve 24, and sent to the use side refrigerant circuits 12a, 12b, 12c to a supercooled state. Then, the cooling circuit side expansion valve 122b of the cooling circuit 122 calculates, for example, the degree of superheat of the cooler 121 (based on the cooling medium temperature detected by the cooling circuit outlet temperature sensor 96 provided in the outlet pipe 122c of the cooling circuit 122). The degree of opening is adjusted according to the flow rate and temperature of the refrigerant sent from the downstream side of the heat source side expansion valve 24 to the use side refrigerant circuits 12a, 12b, 12c.
- the usage unit 3 is in a cooling operation and the usage units 4 and 5 are in a heating / cooling simultaneous operation mode.
- the operation when the heat source side heat exchanger 23 of the heat source unit 2 is operated as an evaporator according to the air conditioning load (evaporation operation state) will be described.
- the refrigerant circuit 12 of the air conditioner 1 is configured as shown in FIG. 6 (refer to the arrows attached to the refrigerant circuit 12 of FIG. 6 for the refrigerant flow).
- the first switching mechanism 22 is set in the evaporation operation state (indicated by the broken line of the first mechanism 22 in FIG.
- the second structure 26 is switched to the heating load required operation state (the state indicated by the broken line of the second structure 26 in Fig. 6), thereby evaporating the heat source side heat exchanger 23.
- the high-pressure gas refrigerant compressed and discharged by the compression mechanism 21 can be supplied to the utilization units 4 and 5 through the high-pressure gas refrigerant communication pipe 10.
- the heat source side expansion valve 24 reduces the refrigerant. The opening degree is adjusted so as to press.
- the on-off valve 11 lb of the pressurizing circuit 111 and the cooling circuit side expansion valve 122b of the cooling circuit 122 are closed, and a high-pressure gas refrigerant is merged with the refrigerant flowing between the heat source side expansion valve 24 and the receiver 25. Or the supply of the cold heat source to the cooler 121 is shut off, and the refrigerant flowing between the receiver 25 and the utilization units 3, 4, and 5 is not cooled.
- the use side heat exchanger 32 of the use unit 3 functions as an evaporator and the use side of the use unit 3
- the heat exchange 32 and the suction side of the compression mechanism 21 of the heat source unit 2 are connected via the low-pressure gas refrigerant communication pipe 11.
- the usage side expansion valve 31 is, for example, a superheat degree of the usage side heat exchanger 32 (specifically, the refrigerant temperature detected by the liquid side temperature sensor 33 and the gas side temperature sensor 34).
- the degree of opening is adjusted according to the cooling load of the unit used, such as by adjusting the degree of opening based on the detected temperature difference from the refrigerant temperature.
- connection units 7 and 8 the low-pressure gas on-off valves 77 and 87 are closed and the high-pressure gas on-off valves 76 and 86 are opened, so that the heat exchange 42 and 52 on the user side 4 and 5 functions as a condenser. I try to let them.
- the usage side expansion valves 41 and 51 are, for example, the degree of supercooling of the usage side heat exchangers 4 and 52 (specifically, the refrigerant detected by the liquid side temperature sensors 43 and 53).
- the degree of opening is adjusted according to the heating load of each usage unit, for example, the degree of opening is adjusted based on the temperature and the refrigerant temperature detected by the gas side temperature sensors 44, 54).
- the high-pressure gas refrigerant compressed and discharged by the compressor 21a of the compression mechanism 21 is mostly contained in the high-pressure gas refrigerant in the oil separator 21b. Separated and sent to Second Unit 26.
- the refrigerating machine oil separated in the oil separator 21b is returned to the suction side of the compressor 21a through the second oil return circuit 21d.
- the high-pressure gas refrigerant sent to the second structure 26 is sent to the high-pressure gas refrigerant communication pipe 10 through the first port 26a and the fourth port 26d of the second structure 26 and the high-pressure gas side closing valve 28. It is done.
- the high-pressure gas refrigerant sent to the high-pressure gas refrigerant communication pipe 10 is branched into two and sent to the high-pressure gas connection pipes 73 and 83 of the connection units 7 and 8.
- the high-pressure gas refrigerant sent to the high-pressure gas connection pipes 73 and 83 of the connection units 7 and 8 is connected to the high-pressure gas on-off valves 76 and 86 and the joints. It is sent to the use side heat exchangers 42 and 52 of the use units 4 and 5 through the flowing gas connection pipes 75 and 85.
- the high-pressure gas refrigerant sent to the use side heat exchangers 42 and 52 is condensed by exchanging heat with indoor air in the use side heat exchangers 42 and 52 of the use units 4 and 5. It is done. On the other hand, indoor air is heated and supplied indoors.
- the refrigerant condensed in the use side heat exchangers 42 and 52 passes through the use side expansion valves 41 and 51 and then is sent to the liquid connection pipes 71 and 81 of the connection units 7 and 8.
- the refrigerant sent to the liquid connection pipes 71 and 81 is sent to the liquid refrigerant communication pipe 9 to be joined.
- a part of the refrigerant sent to and joined to the liquid refrigerant communication pipe 9 is sent to the liquid connection pipe 61 of the connection unit 6. Then, the refrigerant sent to the liquid connection pipe 61 of the connection unit 6 is sent to the use side expansion valve 31 of the use unit 3.
- the refrigerant sent to the use side expansion valve 31 is depressurized by the use side expansion valve 31, and then is evaporated by exchanging heat with indoor air in the use side heat exchanger 32. It becomes a gas refrigerant.
- indoor air is cooled and supplied indoors.
- the low-pressure gas refrigerant is sent to the merged gas connection pipe 65 of the connection unit 6.
- the low-pressure gas refrigerant sent to the merged gas connection pipe 65 is sent to the low-pressure gas refrigerant communication pipe 11 through the low-pressure gas on-off valve 67 and the low-pressure gas connection pipe 64 and merges.
- the low-pressure gas refrigerant sent to the low-pressure gas refrigerant communication pipe 11 is returned to the suction side of the compression mechanism 21 through the low-pressure gas side closing valve 29.
- the remaining refrigerant excluding the refrigerant sent from the liquid refrigerant communication pipe 9 to the connection unit 6 and the utilization unit 3 is sent to the resin 25 through the liquid side closing valve 27 and the cooler 121 of the heat source unit 2.
- the refrigerant sent to the receiver 25 is temporarily stored in the receiver 25 and then decompressed by the heat source side expansion valve 24.
- the refrigerant depressurized by the heat source side expansion valve 24 is evaporated by exchanging heat with water as a heat source in the heat source side heat exchange 23 to become a low pressure gas refrigerant. Sent.
- the low-pressure gas refrigerant sent to the first structure 22 is returned to the suction side of the compression mechanism 21 through the second port 22b and the third port 22c of the first structure 22. In this way, cool and warm simultaneous luck Operation in rotation mode (evaporation load) is performed.
- the heat source side heat exchange requires an evaporation load, but the size may be very small.
- the refrigerant evaporation capacity in the heat source side heat exchanger 23 of the heat source unit 2 is reduced, and the air conditioning load and balance of the entire usage units 3, 4, and 5 are reduced. I have to let it.
- the cooling load of the utilization unit 3 and the heating load of the utilization units 4 and 5 may be approximately the same load.
- the evaporation load of the heat source side heat exchanger 23 must be very small.
- the air conditioner 1 of the present embodiment uses a combination of refrigerating machine oil and refrigerant that do not separate into two layers within a temperature range of 30 ° C. or lower (more preferably, lower than the minimum value of the evaporation temperature).
- the heat source side heat exchanger functions as an evaporator, it is used in the heat source side heat exchanger and is not separated into two layers, but uses a combination of refrigerating machine oil and refrigerant. Since the circuit 101 is provided, it becomes possible to prevent the refrigerating machine oil from being accumulated in the heat source side heat exchanger 23 as described in the operation description of the heating operation mode described above! /,
- the entire usage units 3, 4 and 5 are empty.
- the operation when the heat source side heat exchange 23 of the heat source unit 2 is operated as a condenser according to the control load (condensing operation state) will be described.
- the refrigerant circuit 12 of the air conditioner 1 is configured as shown in FIG. 7 (refer to the arrows attached to the refrigerant circuit 12 of FIG. 7 for the refrigerant flow).
- the first switching mechanism 22 is switched to the condensing operation state (the state indicated by the solid line of the first switching mechanism 22 in FIG. 7), and the second switching is performed.
- the mechanism 26 By switching the mechanism 26 to the heating load required operation state (the state indicated by the broken line in the second mechanism 26 in FIG. 7), the heat source side heat exchange 23 functions as an evaporator and the high pressure gas refrigerant communication pipe 10 is used.
- the use unit 5 can be supplied with the high-pressure gas refrigerant compressed and discharged by the compression mechanism 21. ing.
- the heat source side expansion valve 24 is in an opened state.
- connection units 6 and 7 the high-pressure gas on-off valves 66 and 76 are closed and the low-pressure gas on-off valves 67 and 77 are opened, so that the use side heat exchangers 32 and 42 of the use units 3 and 4 are used as evaporators.
- the usage side heat exchange 32, 42 of the usage units 3, 4 and the suction side of the compression mechanism 21 of the heat source unit 2 are connected via the low-pressure gas refrigerant communication pipe 11. Yes.
- the usage side expansion valves 31 and 41 include, for example, the degree of superheat of the usage side heat exchange 32 and 42 (specifically, the coolant temperature detected by the liquid side temperature sensors 33 and 43).
- the opening degree is adjusted according to the cooling load of each usage unit, for example, the opening degree is adjusted based on the temperature difference between the refrigerant and the refrigerant temperature detected by the gas side temperature sensors 34 and 44.
- the low-pressure gas on-off valve 87 is closed and the high-pressure gas on-off valve 86 is opened so that the use side heat exchange of the use unit 5 functions as a condenser.
- the usage-side expansion valve 51 includes, for example, the degree of supercooling of the usage-side heat exchanger 52 (specifically, the refrigerant temperature detected by the liquid-side temperature sensor 53 and the gas-side temperature sensor 54.
- the degree of opening is adjusted according to the heating load of the unit used, such as the degree of opening is adjusted based on the detected temperature difference from the refrigerant temperature.
- the high-pressure gas refrigerant compressed and discharged by the compressor 21a of the compression mechanism 21 is mostly contained in the high-pressure gas refrigerant in the oil separator 21b. It is separated and sent to the first structure 22 and the second structure 26. The refrigerating machine oil separated in the oil separator 21b is returned to the suction side of the compressor 21a through the second oil return circuit 21d.
- the high-pressure gas refrigerant sent to the first switching mechanism 22 passes through the first port 22a and the second port 22b of the first switching mechanism 22, and the heat source Sent to side heat exchange 23.
- the high-pressure gas refrigerant sent to the heat source side heat exchanger 23 is condensed by exchanging heat with water as a heat source in the heat source side heat exchanger 23.
- the refrigerant condensed in the heat source side heat exchanger 23 passes through the heat source side expansion valve 24, and then the high pressure gas refrigerant compressed and discharged by the compression mechanism 21 through the pressurizing circuit 111 joins (details).
- Receiver) 25 Sent to.
- the refrigerant sent to the receiver 25 is temporarily stored in the receiver 25 and then sent to the cooler 121.
- the refrigerant sent to the cooler 121 is cooled by exchanging heat with the refrigerant flowing through the cooling circuit 122 (details will be described later).
- the refrigerant cooled in the cooler 121 is sent to the liquid refrigerant communication pipe 9 through the liquid side closing valve 27.
- the high-pressure gas refrigerant sent to the second mechanism 26 is the first port 26a and the fourth port 26d of the second switching mechanism 26. Then, it is sent to the high-pressure gas refrigerant communication pipe 10 through the high-pressure gas side closing valve 28.
- the high-pressure gas refrigerant sent to the high-pressure gas refrigerant communication pipe 10 is sent to the high-pressure gas connection pipe 83 of the connection unit 8.
- the high-pressure gas refrigerant sent to the high-pressure gas connection pipe 83 of the connection unit 8 is sent to the use-side heat exchanger 52 of the use unit 5 through the high-pressure gas on-off valve 86 and the merged gas connection pipe 85.
- the high-pressure gas refrigerant sent to the use-side heat exchanger 52 is condensed by exchanging heat with indoor air in the use-side heat exchanger 52 of the use unit 5. On the other hand, indoor air is heated and supplied indoors.
- the refrigerant condensed in the use side heat exchanger 52 is sent to the liquid connection pipe 81 of the connection unit 8 after passing through the use side expansion valve 51.
- the refrigerant sent to the liquid connection pipe 81 is sent to the liquid refrigerant communication pipe 9, where the first switching mechanism 22, the heat source side heat exchanger 23, the heat source side expansion valve 24, the receiver 25, the cooling
- the refrigerant is sent to the liquid refrigerant communication pipe 9 through the vessel 121 and the liquid side closing valve 27.
- the refrigerant flowing through the liquid refrigerant communication pipe 9 is branched into two and sent to the liquid connection pipes 61 and 71 of the connection units 6 and 7. Then, the refrigerant sent to the liquid connection pipes 61 and 71 of the connection units 6 and 7 is sent to the use side expansion valves 31 and 41 of the use units 3 and 4.
- the refrigerant sent to the use side expansion valves 31 and 41 is depressurized by the use side expansion valves 31 and 41 and then exchanges heat with indoor air in the use side heat exchangers 32 and 42. It is evaporated and becomes a low-pressure gas refrigerant. On the other hand, indoor air is cooled and supplied indoors. Then, the low-pressure gas refrigerant is sent to the merged gas connection pipes 65 and 75 of the connection units 6 and 7.
- the low-pressure gas refrigerant sent to the merged gas connection pipes 65, 75 is supplied to the low-pressure gas on-off valve 67. , 77 and the low-pressure gas connection pipes 64 and 74 to the low-pressure gas refrigerant communication pipe 11 to join.
- the low-pressure gas refrigerant sent to the low-pressure gas refrigerant communication pipe 11 is returned to the suction side of the compression mechanism 21 through the low-pressure gas side closing valve 29. In this way, the operation is performed in the cooling and heating simultaneous operation mode (condensation load).
- the heat source side heat exchange requires a condensing load, which may be very small.
- the refrigerant condensing capacity in the heat source side heat exchanger 23 of the heat source unit 2 is reduced, and the air conditioning load and balance of the entire usage units 3, 4, and 5 are reduced. I have to let it.
- the cooling load of the usage units 3 and 4 and the heating load of the usage unit 5 may be approximately the same load.
- the condensation load of the heat source side heat exchanger 23 must be very small.
- a high-pressure gas refrigerant is joined to the downstream side of the heat source side expansion valve 24 through the pressurization circuit 111 while performing control to reduce the opening degree of the heat source side expansion valve 24.
- control is performed to increase the pressure of the refrigerant on the downstream side of the heat source side expansion valve 24, and the refrigerant that is decompressed by the heat source side expansion valve 24 and sent to the use side refrigerant circuits 12a and 12b is cooled by the cooler 121. Since cooling is performed, the gas refrigerant can be condensed, and it is not necessary to send a gas-liquid two-phase flow refrigerant with a large gas fraction to the use-side refrigerant circuits 12a and 12b.
- the air conditioner 1 of the present embodiment has the following features.
- a heat source side refrigerant circuit 12d having a heat source side heat exchanger 23 configured so that refrigerant flows in from the lower side and flows out from the upper side.
- the refrigerant circuit 12 is configured by connecting a plurality of usage-side refrigerant circuits 12a, 12b, and 12c, and the refrigerating machine oil and refrigerant used in the refrigerant circuit 12 are 30 ° C or less (more preferably Is separated into two layers in the temperature range below the minimum evaporation temperature) There is no combination of refrigeration oil and refrigerant.
- the evaporation temperature of the refrigerant in the heat source side heat exchange is a temperature of 30 ° C. or less (and more than the minimum value of the evaporation temperature) when water, air, or brine is used as the heat source.
- the refrigerating machine oil and refrigerant used in this refrigerant circuit when the heat source side heat exchanger functions as an evaporator, the refrigerating machine oil is not separated into two layers in the heat source side heat exchanger. And refrigerant is used.
- the refrigerating machine oil accumulates in the heat source side heat exchanger in a mixed state with the refrigerant that does not accumulate in the state of floating on the liquid level of the refrigerant in the heat source side heat exchanger 23.
- the refrigerating machine oil accumulated in the heat source side heat exchanger is returned to the suction side of the compression mechanism 21 together with the refrigerant by the first oil return circuit 101 connected to the lower part of the heat source side heat exchanger 23. .
- the liquid level of the refrigerant in the heat source side heat exchanger should be at a certain level or higher. Need not be maintained.
- the evaporation capacity of the heat source side heat exchange is reduced by reducing the opening degree of the heat source side expansion valve 24 according to the air conditioning load of the plurality of use side refrigerant circuits 12a, 12b, and 12c.
- the evaporation capacity of the heat source side heat exchange 23 This makes it possible to expand the control range when controlling the heat source side expansion valve.
- the air conditioner 1 when a plurality of heat source side heat exchangers are provided and the heat source side heat exchange functions as an evaporator, some of the plurality of heat source side expansion valves are used.
- the number of heat source side heat exchangers ⁇ that function as evaporators and reducing the evaporation capacity, or by allowing some of the heat source side heat exchangers ⁇ to function as condensers Since it is not necessary to control to reduce the evaporation capacity by offsetting the evaporation capacity of the heat source side heat exchanger functioning as an evaporator, a wide range of evaporation capacity control can be obtained by a single heat source side heat exchange Will be able to.
- the first oil return circuit 101 is provided with the on-off valve 101b, and when the heat source side heat exchange 23 functions as a condenser, the on-off valve 101b is closed.
- the on-off valve 101b is closed.
- a plate-type heat exchanger is used as the heat source side heat exchanger 23. Due to its structure, a refrigerant is used to prevent refrigeration oil from collecting in the heat source side heat exchanger 23. It is difficult to extract the refrigerating machine oil that has floated and accumulated above the liquid level from the vicinity of the refrigerant level.
- the refrigerating machine oil is stored in the heat source side heat exchanger 23 in a state of being mixed with the refrigerant, and the refrigerating machine oil accumulated in the heat source side heat exchanger 23 is combined with the refrigerant in the heat source side heat. Even if a plate heat exchanger is used, the first oil return circuit 101 can be easily installed because it is only necessary to extract the lower force of the AC.
- the refrigerant condensed in the heat source side heat exchanger 23 functioning as a condenser is decompressed by the heat source side expansion valve 24 and sent to the use side refrigerant circuits 12a, 12b, 12c.
- the high-pressure gas refrigerant merges from the pressurizing circuit 111 and is pressurized, and the refrigerant pressure on the downstream side of the heat source side expansion valve 24 is increased.
- the refrigerant sent to the use-side refrigerant circuits 12a, 12b, 12c becomes a gas-liquid two-phase flow with a large gas fraction,
- the opening degree of the heat source side expansion valve 24 cannot be made sufficiently small, in the air conditioner 1, the pressure is reduced by the heat source side expansion valve 24 to the use side refrigerant circuits 12a, 12b, 12c. Since the refrigerant to be sent is cooled by the cooler 121, the gas refrigerant can be condensed, and a gas-liquid two-phase flow refrigerant having a large gas fraction in the use side refrigerant circuits 12a, 12b, 12c. You don't have to send
- the condensation capacity of the heat source side heat exchanger 23 is reduced by reducing the opening degree of the heat source side expansion valve 24 according to the air conditioning load of the plurality of use side refrigerant circuits 12a, 12b, 12c.
- pressurization circuit 111 is used to consolidate and pressurize high-pressure gas refrigerant, gas-liquid two-phase flow refrigerant with a large gas fraction is not sent to use-side refrigerant circuits 12a, 12b, and 12c. Therefore, it is possible to expand the control range when controlling the evaporation capability of the heat source side heat exchange by the heat source side expansion valve 24.
- the air conditioner 1 when a plurality of heat source side heat exchangers are provided and the heat source side heat exchange functions as a condenser, as in the conventional air conditioner, some of the plurality of heat source side expansion valves are used.
- the number of heat source side heat exchangers ⁇ that function as evaporators and reducing the evaporation capacity, or by allowing some of the heat source side heat exchangers ⁇ to function as condensers Since it is not necessary to control to reduce the evaporation capacity by offsetting the evaporation capacity of the heat source side heat exchanger functioning as an evaporator, a wide range of condensation capacity control can be obtained by a single heat source side heat exchange Will be able to.
- the pressurization circuit 111 is connected so that the high-pressure gas refrigerant merges between the heat source side expansion valve 24 and the cooler 121. Therefore, the high-pressure gas refrigerant merges. Then, the refrigerant whose temperature has been increased is cooled by the cooler 121. As a result, a relatively high temperature cold heat source that does not require the use of a low temperature cold heat source can be used as the cold heat source for cooling the refrigerant in the cooler 121.
- a part of the refrigerant sent from the downstream side of the heat source side expansion valve 24 to the use side refrigerant circuits 12a, 12b, 12c is reduced to a refrigerant pressure that can be returned to the suction side of the compression mechanism 21. Since this is used as the cooling source for the cooler 121, the cooling source has a temperature sufficiently lower than the temperature of the refrigerant sent from the downstream side of the heat source side expansion valve 24 to the utilization side refrigerant circuit 12a, 12b, 12c. Can be obtained. This makes it possible to cool the refrigerant sent from the downstream side of the heat source side expansion valve 24 to the utilization side refrigerant circuits 12a, 12b, and 12c to a supercooled state.
- water that is supplied in a constant amount is used as a heat source regardless of the flow control of the refrigerant flowing in the heat source side heat exchanger 23, and the heat source side heat is controlled by controlling the amount of water. It is impossible to control the evaporation capacity in the exchange. However, in the air conditioner 1, since the control range when the evaporation capacity or the condensation capacity of the heat source side heat exchanger 23 is controlled by the heat source side expansion valve 24 is expanded, it is not necessary to control the amount of water. Thus, it is possible to secure a control range when controlling the evaporation capability of the heat source side heat exchanger 23.
- the heat source unit 2 and the utilization units 3, 4, and 5 are connected to the refrigerant communication pipes 9, 10, 11, and Although connected via connection units 6, 7, and 8, as shown in Fig. 8, in order to construct an air conditioner capable of switching between cooling and heating, the heat source unit 2 and the utilization units 3, 4, 5 and may be connected via the refrigerant communication pipes 9 and 10 only.
- the low-pressure gas refrigerant communication pipe 11 and the connection units 6, 7, and 8 necessary for enabling simultaneous operation of cooling and heating are omitted, and the usage units 3, 4 , 5 are directly connected to the liquid refrigerant communication pipe 9 and the high-pressure gas refrigerant communication pipe 10, and by switching the second switching mechanism 26, the high-pressure gas refrigerant communication pipe 10 is changed from the use unit 3, 4, 5 to the heat source unit 2.
- It can function as a pipe through which the returned low-pressure gas refrigerant flows, or it can function as a pipe through which the high-pressure gas refrigerant supplied from the heat source unit 2 to the utilization units 3, 4, and 5 flows. I have to.
- the heating operation mode will be described.
- the refrigerant circuit 12 of the air conditioner 1 is configured as shown in FIG. 9 (the refrigerant flow is attached to the refrigerant circuit 12 of FIG. 9). (See the arrow that appears.)
- the first Kiriura structure 22 is switched to the evaporation operation state (the state indicated by the broken line of the first switching mechanism 22 in FIG. 9), and the second By switching the switching mechanism 26 to the heating load demand operation state (the state indicated by the broken line in the second mechanism 26 in FIG.
- the heat source side heat exchanger 23 functions as an evaporator and the high pressure
- the high-pressure gas refrigerant compressed and discharged by the compression mechanism 21 can be supplied to the utilization units 3, 4, and 5 through the gas refrigerant communication pipe 10.
- the opening degree of the heat source side expansion valve 24 is adjusted so as to depressurize the refrigerant.
- the on-off valve 111b of the pressurizing circuit 111 and the cooling circuit side expansion valve 122b of the cooling circuit 122 are closed, and a high-pressure gas refrigerant is combined with the refrigerant flowing between the heat source side expansion valve 24 and the receiver 25.
- the supply of the cold heat source to the cooler 121 is cut off, and the refrigerant flowing between the receiver 25 and the utilization units 3, 4, and 5 is not cooled.
- the usage side expansion valves 31, 41, and 51 are, for example, the degree of supercooling of the usage side heat exchangers 32, 42, and 52 (specifically, the liquid side temperature sensors 33, 43).
- the high-pressure gas refrigerant compressed and discharged by the compressor 21a of the compression mechanism 21 is supplied to the high-pressure gas refrigerant in the oil separator 21b. Most of them are separated and sent to the second structure 26.
- the refrigerating machine oil separated in the oil separator 21b is returned to the suction side of the compressor 21a through the second oil return circuit 21d.
- the high-pressure gas refrigerant sent to the second structure 26 is sent to the high-pressure gas refrigerant communication pipe 10 through the first port 26a and the fourth port 26d of the second structure 26 and the high-pressure gas side closing valve 28. It is done.
- the high-pressure gas refrigerant sent to the high-pressure gas refrigerant communication pipe 10 is branched into three and sent to the use side heat exchangers 32, 42, 52 of the use units 3, 4, 5.
- the high-pressure gas refrigerant sent to the use side heat exchangers 32, 42, 52 exchanges heat with indoor air in the use side heat exchangers 32, 42, 52 of the use units 3, 4, 5. It is condensed by this. On the other hand, indoor air is heated and supplied indoors.
- the refrigerant condensed in the use side heat exchangers 32, 42, 52 passes through the use side expansion valves 31, 41, 51 and then is sent to the liquid refrigerant communication pipe 9 to join.
- the refrigerant sent to the liquid refrigerant communication pipe 9 and merged is sent to the receiver 25 through the liquid side closing valve 27 and the cooler 121 of the heat source unit 2.
- the refrigerant sent to the receiver 25 is temporarily stored in the receiver 25 and then decompressed by the heat source side expansion valve 24.
- the refrigerant decompressed by the heat source side expansion valve 24 is evaporated by exchanging heat with water as a heat source in the heat source side heat exchanger 23 to become a low-pressure gas refrigerant. Sent.
- the low-pressure gas refrigerant sent to the first mechanism 22 is returned to the suction side of the compression mechanism 21 through the second port 22b and the third port 22c of the first switching mechanism 22. In this way, the operation in the heating operation mode is performed.
- the heating load of each usage unit 3, 4, and 5 may be very small, but it is separated into two layers in a temperature range of 30 ° C or less (more preferably, the minimum evaporation temperature).
- the first oil return circuit 101 is provided in addition to the combination of refrigeration oil and refrigerant), so that the heat source side heat is similar to the heating operation mode of the air conditioner configured to allow simultaneous cooling and heating operation. It is possible to prevent refrigeration oil from accumulating inside the station.
- the refrigerant circuit 12 of the air conditioner 1 is configured as shown in FIG. 10 (the refrigerant flow is attached to the refrigerant circuit 12 of FIG. 10). (See the arrow that appears.)
- the first notch structure 22 is switched to the condensing operation state (the state indicated by the solid line of the first switching mechanism 22 in FIG. 10), and the second By switching the switching mechanism 26 to the cooling operation state at the time of cooling / heating switching (the state indicated by the solid line of the second switching mechanism 26 in FIG.
- the heat source side heat exchange 23 functions as a condenser and a high-pressure gas refrigerant.
- the low-pressure gas refrigerant returned from the utilization units 3, 4, 5 to the heat source unit 2 through the communication pipe 10 can be sent to the suction side of the compression mechanism 21.
- the heat source side expansion valve 24 is in an opened state.
- the on-off valve 101b of the first oil return circuit 101 is closed, and the lower force of the heat source side heat exchange is also in a state in which the operation of extracting the refrigerating machine oil together with the refrigerant and returning it to the compressor mechanism 21 is not performed.
- the usage side expansion valves 31, 41, and 51 are, for example, the degree of superheat of the usage side heat exchangers 32, 42, and 52 (specifically, the liquid side temperature sensors 33, 43).
- the opening is adjusted.
- the high-pressure gas refrigerant compressed and discharged by the compressor 21a of the compression mechanism 21 is stored in the high-pressure gas refrigerant in the oil separator 21b. Most of them are separated and sent to the first switching mechanism 22.
- the refrigerating machine oil separated in the oil separator 21b is returned to the suction side of the compressor 21a through the second oil return circuit 21d.
- the high-pressure gas refrigerant sent to the first switching mechanism 22 is sent to the heat source side heat exchanger 23 through the first port 22a and the second port 22b of the first switching mechanism 22.
- the high-pressure gas refrigerant sent to the heat source side heat exchanger 23 is condensed by exchanging heat with water as the heat source in the heat source side heat exchanger 23.
- heat source side heat exchange 23 After passing through the heat source side expansion valve 24, the high-pressure gas refrigerant compressed and discharged by the compression mechanism 21 passes through the pressurizing circuit 111 and is sent to the receiver 25.
- the refrigerant sent to the receiver 25 is temporarily stored in the receiver 25 and then sent to the cooler 121.
- the refrigerant sent to the cooler 121 is cooled by exchanging heat with the refrigerant flowing through the cooling circuit 122. Then, the refrigerant cooled in the cooler 121 is sent to the liquid refrigerant communication pipe 9 through the liquid side closing valve 27.
- the refrigerant sent to the liquid refrigerant communication pipe 9 is branched into three and sent to the use side expansion valves 31, 41, 51 of the use units 3, 4, 5.
- the refrigerant sent to the use side expansion valves 31, 41, 51 is depressurized by the use side expansion valves 31, 41, 51, and then exchanges heat with indoor air in the use side heat exchangers 32, 42, 52. Is evaporated into a low-pressure gas refrigerant. On the other hand, indoor air is cooled and supplied indoors. Then, the low-pressure gas refrigerant is sent to the high-pressure gas refrigerant communication pipe 10 and merges.
- the low-pressure gas refrigerant that has been sent to the high-pressure gas refrigerant communication pipe 10 and joined therethrough passes through the high-pressure gas side closing valve 28 and the fourth port 26d and the third port 26c of the second structure 26, and the compression mechanism 21 It is returned to the suction side. In this way, the operation in the cooling operation mode is performed.
- the cooling load of each of the usage units 3, 4, and 5 may be very small.
- the downstream side of the heat source side expansion valve 24 is controlled.
- the high-pressure gas refrigerant is joined to the refrigerant through the pressurizing circuit 111 to increase the pressure of the refrigerant on the downstream side of the heat source side expansion valve 24, and the pressure is reduced by the heat source side expansion valve 24 to be used. Since the refrigerant sent to 12a, 12b, and 12c is cooled by the cooler 121, the gas refrigerant is condensed in the same manner as in the cooling operation mode of the air conditioner configured to be capable of simultaneous cooling and heating. Therefore, it is not necessary to send a gas-liquid two-phase refrigerant having a large gas fraction to the use side refrigerant circuits 12a, 12b, 12c.
- the heat source side heat exchanger 23 of the heat source side expansion valve 24 In order to expand both the control range of the evaporation capacity control and the control range of the control of the condensation capacity of the heat source side heat exchanger 23 by the heat source side expansion valve 24, the first oil return circuit 101, the pressure circuit 111
- the heat source unit 2 is provided with the cooler 121 and the cooling circuit 122.
- the control range for controlling the condensation capacity of the heat source side heat exchanger 23 is secured, but the evaporation of the heat source side heat exchanger 23 is secured.
- only the first oil return circuit 101 i.e., the pressurization circuit 111, the cooler 121 and the cooling circuit 122 are connected
- the heat source unit 2 that is, the pressurization circuit 111, the cooler 121, and the cooling circuit 122 may be omitted.
- four-way switching valves are used as the first switching mechanism 22 and the second switching mechanism 26, but the present invention is not limited to this.
- a three-way valve may be used as the mechanism 22 and the second mechanism 26.
- the flow rates of the refrigerating machine oil and the refrigerant that return the lower force of the heat source side heat exchange functioning as an evaporator through the first oil return circuit 101 to the compression mechanism 21 are also in the first oil return circuit 101. Since it is determined according to the pressure loss between the lower part of the heat source side heat exchange 23 that functions as an evaporator and the compression mechanism 21, for example, in the heat source side heat exchanger 23 that functions as an evaporator or heat source side heat Heat source side heat when the pressure loss force in the piping from the refrigerant outlet side of the exchanger 23 to the suction side of the compression mechanism 21 or the pressure loss in the first oil return circuit 101 is reduced.
- Refrigerator oil and refrigerant at a flow rate sufficient to prevent the refrigeration oil from accumulating in the exchanger 23 can be returned to the compression mechanism 21 through the first oil return circuit 101 and also to the lower force of the heat source side heat exchange. There may be cases where it does not occur.
- the refrigeration oil and refrigerant at a flow rate sufficient to prevent the refrigeration oil from accumulating in the heat source side heat exchanger 23 are supplied to the heat source side heat exchange through the first oil return circuit 101.
- the lower force of the compressor is also returned to the compression mechanism 21 between the refrigerant outlet side of the heat source side heat exchanger 23 functioning as an evaporator and the suction side of the compression mechanism 21. Is connected between them and evaporated at the heat source side heat exchanger 23.
- the pressure of the gas refrigerant returned to the suction side of the compression mechanism 21 can be reduced before the lower force of heat exchange on the heat source side through the first oil return circuit 101 is combined with the refrigeration oil and refrigerant returned to the compression mechanism 21.
- a mechanism 131 may be further provided.
- the pressure reducing mechanism 131 mainly includes an on-off valve 131a that also has an electromagnetic valve force connected to a pipe that connects the third port 22c of the first switching mechanism 22 and the suction side of the compression mechanism 21, and a bypass that bypasses the on-off valve 131a. It consists of 13 lb tube. A capillary tube 13 lc is connected to the bypass pipe 131b. In the pressure reducing mechanism 131, when the first oil return circuit 101 is used, the on-off valve 131a is closed so that only the bypass pipe 131b flows the gas refrigerant evaporated in the heat source side heat exchanger 23.
- the first oil return circuit 101 is provided.
- the pressure loss between the refrigerant outlet side of the heat source side heat exchanger 23 functioning as an evaporator and the suction side of the compression mechanism 21 is increased (that is, the decompression mechanism 131 is connected to the first oil
- the first oil return circuit is configured to function as a differential pressure increase mechanism that increases the differential pressure until the lower force of the heat source side heat exchange is returned to the compression mechanism 21 through the return circuit 101 and merges with the refrigeration oil and refrigerant.
- the lower force of the alternating force can also increase the flow rates of the refrigerating machine oil and the refrigerant returned to the compression mechanism 21. This ensures that the refrigerating machine oil and refrigerant having a flow rate sufficient to prevent the refrigerating machine oil from accumulating in the heat source side heat exchanger 23 are surely supplied through the first oil return circuit 101 to the heat source side heat exchanger 2.
- the lower force of 3 can also be returned to the compression mechanism 21. If the pressure loss in the bypass pipe 131b can be appropriately set without connecting the capillary tube 131c, the capillary tube 131c is unnecessary.
- the pressure reducing mechanism as the differential pressure increasing mechanism is a third port 22c of the first switching mechanism 22 as shown in FIG. 14 which is not the on-off valve 131a and the bypass pipe 13lb such as the pressure reducing mechanism 131 described above.
- an electric expansion valve connected to a pipe connecting the suction side of the compression mechanism 21 may be used.
- the decompression mechanism 141 when the first oil return circuit 101 is used, the decompression mechanism 21 is controlled from the refrigerant outlet side of the heat source side heat exchanger 23 that functions as an evaporator by performing control to reduce the opening degree. Increase the pressure loss up to the suction side and adjust the first oil return circuit 101.
- the lower force of the heat source side heat exchange can also be increased so that the flow rate of the refrigerating machine oil and refrigerant returned to the compression mechanism 21 can be increased.
- the opening degree is increased (for example, fully opened). Therefore, the refrigeration oil and refrigerant at a flow rate sufficient to prevent the refrigeration oil from accumulating in the heat source side heat exchange 23 are reliably supplied to the heat source side heat through the first oil return circuit 101.
- the lower force of the alternating force can also be returned to the compression mechanism 21.
- the first oil return circuit 101 may be provided with a pump mechanism 151 as a differential pressure increasing mechanism as shown in FIG. 15 without using the pressure reducing mechanism 131 and the pressure reducing mechanism 141 as described above.
- the pump mechanism 151 can use a refrigerant pump.
- the pump mechanism 151 pressurizes the refrigeration oil accumulated in the heat source side heat exchanger 23 and sends it to the first oil return circuit 101 (that is, the pump mechanism 151 passes through the first oil return circuit 101 to heat source side heat.
- the lower force of the exchanger 23 also functions as a differential pressure increasing mechanism that increases the differential pressure until it merges with the refrigeration oil and refrigerant returned to the compression mechanism 21), and the heat exchange on the heat source side through the first oil return circuit 101.
- This lower force can also increase the flow rate of the refrigerating machine oil and refrigerant returned to the compression mechanism 21. This ensures that the refrigerating machine oil and refrigerant at a flow rate sufficient to prevent the refrigerating machine oil from accumulating in the heat source side heat exchanger 23 are reliably transferred through the first oil return circuit 101. The lower force can also be returned to the compression mechanism 21.
- an ejector mechanism 161 as a differential pressure increasing mechanism may be provided.
- the ejector mechanism 161 mainly includes an ejector 16 la provided in the first oil return circuit 101 and a high-pressure gas refrigerant serving as a driving fluid for the ejector 16 la on the discharge side of the compression mechanism 21 (in this modification, an oil separator). 21b and the first port 22a of the first switching mechanism 22), and a branch pipe 161b branched from the branch pipe 161b and an open / close valve 161c provided on the branch pipe 161b.
- the on-off valve 161a is opened to supply the high-pressure gas refrigerant as the driving fluid to the discharge-side force ejector 161a of the compression mechanism 21, and the high-pressure gas refrigerant
- sucking the refrigeration oil accumulated in the lower part of the heat source side heat exchanger 23 and sending it to the first oil return circuit 101 that is, the ejector mechanism 161 is exchanged through the first oil return circuit 101 for heat source side heat exchange.
- the lower force of the compressor 23 is made to function as a differential pressure increasing mechanism that increases the differential pressure until the refrigerant oil and refrigerant returned to the compression mechanism 21 are merged), and through the first oil return circuit 101, the heat source side
- the lower force of heat exchange can also increase the flow rate of the refrigerating machine oil and refrigerant returned to the compression mechanism 21. This ensures that the refrigerating machine oil and refrigerant at a flow rate sufficient to prevent the refrigerating machine oil from accumulating in the heat source side heat exchange, and also compresses the lower force of the heat source side heat exchange through the first oil return circuit 101. Return to Mechanism 21.
- a refrigeration apparatus and an air conditioner having a refrigerant circuit having an evaporator configured to allow refrigerant to flow in from the lower side and out of the upper force! It is possible to expand the control range when controlling the evaporation capacity of the gas using the expansion valve.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Air Conditioning Control Device (AREA)
- Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
- Compression-Type Refrigeration Machines With Reversible Cycles (AREA)
Abstract
Description
Claims
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US11/630,104 US20070245752A1 (en) | 2004-07-01 | 2005-06-29 | Refrigerating Apparatus and Air Conditioner |
AU2005258567A AU2005258567B2 (en) | 2004-07-01 | 2005-06-29 | Refrigerating apparatus and air conditioner |
EP05765416.2A EP1780479A4 (en) | 2004-07-01 | 2005-06-29 | COOLER AND AIR CONDITIONER |
JP2006528741A JP4475278B2 (ja) | 2004-07-01 | 2005-06-29 | 冷凍装置及び空気調和装置 |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2004-195228 | 2004-07-01 | ||
JP2004195228 | 2004-07-01 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2006003925A1 true WO2006003925A1 (ja) | 2006-01-12 |
Family
ID=35782733
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2005/011930 WO2006003925A1 (ja) | 2004-07-01 | 2005-06-29 | 冷凍装置及び空気調和装置 |
Country Status (6)
Country | Link |
---|---|
US (1) | US20070245752A1 (ja) |
EP (1) | EP1780479A4 (ja) |
JP (1) | JP4475278B2 (ja) |
CN (1) | CN1981165A (ja) |
AU (1) | AU2005258567B2 (ja) |
WO (1) | WO2006003925A1 (ja) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2008047988A2 (en) | 2006-10-17 | 2008-04-24 | Lg Electronics Inc. | Water-cooled air conditioner |
JP2009079820A (ja) * | 2007-09-26 | 2009-04-16 | Sanyo Electric Co Ltd | 冷凍サイクル装置 |
JP2011247579A (ja) * | 2011-08-08 | 2011-12-08 | Mitsubishi Electric Corp | プレート式熱交換器及び冷凍空調装置 |
WO2014103173A1 (ja) * | 2012-12-28 | 2014-07-03 | ダイキン工業株式会社 | 空気調和装置及び空気調和装置の施工方法 |
WO2014108997A1 (ja) * | 2013-01-08 | 2014-07-17 | 三菱電機株式会社 | 空気調和装置 |
Families Citing this family (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3861891B2 (ja) * | 2004-08-04 | 2006-12-27 | ダイキン工業株式会社 | 空気調和装置 |
JP4492638B2 (ja) | 2007-05-09 | 2010-06-30 | 株式会社日立製作所 | プラズマディスプレイパネル、プラズマディスプレイパネルの基板構体 |
DE102007041281A1 (de) | 2007-08-31 | 2009-07-23 | Airbus Deutschland Gmbh | Flugzeugkühlanlagenverdampferanordnung für zwei voneinander unabhängige Kälteträgerkreisläufe |
JP5316074B2 (ja) * | 2009-02-24 | 2013-10-16 | ダイキン工業株式会社 | ヒートポンプシステム |
WO2011030418A1 (ja) * | 2009-09-10 | 2011-03-17 | 三菱電機株式会社 | 空気調和装置 |
CN102713460B (zh) * | 2009-12-28 | 2016-03-02 | 大金工业株式会社 | 热泵系统 |
KR101633781B1 (ko) * | 2010-03-05 | 2016-06-27 | 엘지전자 주식회사 | 칠러 |
CN101852509B (zh) * | 2010-05-21 | 2011-11-09 | 北京中科华誉能源技术发展有限责任公司 | 制冷剂侧冷热换向的满液式水源热泵机组 |
US9657977B2 (en) * | 2010-11-17 | 2017-05-23 | Hill Phoenix, Inc. | Cascade refrigeration system with modular ammonia chiller units |
US9664424B2 (en) | 2010-11-17 | 2017-05-30 | Hill Phoenix, Inc. | Cascade refrigeration system with modular ammonia chiller units |
CN103743156B (zh) * | 2014-01-06 | 2016-08-17 | 丹佛斯微通道换热器(嘉兴)有限公司 | 热泵系统 |
WO2015188266A1 (en) * | 2014-06-10 | 2015-12-17 | Vmac Global Technology Inc. | Methods and apparatus for simultaneously cooling and separating a mixture of hot gas and liquid |
GB2565665B (en) * | 2016-06-14 | 2020-11-11 | Mitsubishi Electric Corp | Air conditioning system |
US20180238592A1 (en) * | 2017-02-17 | 2018-08-23 | Mark W Miles | Solar driven ejector heat pumps for supplemental heating and cooling resources |
WO2021082331A1 (zh) * | 2019-10-28 | 2021-05-06 | 广东美的制冷设备有限公司 | 空调器 |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS62276368A (ja) * | 1986-05-23 | 1987-12-01 | 株式会社ボッシュオートモーティブ システム | 空調装置における油戻し機構 |
JPH0755268A (ja) * | 1993-08-09 | 1995-03-03 | Nippondenso Co Ltd | 冷凍装置 |
JPH10160293A (ja) * | 1996-11-29 | 1998-06-19 | Sanyo Electric Co Ltd | 冷凍装置及びアキュームレータ |
JP2003287291A (ja) * | 2002-03-27 | 2003-10-10 | Mitsubishi Electric Corp | 冷凍装置 |
Family Cites Families (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3633377A (en) * | 1969-04-11 | 1972-01-11 | Lester K Quick | Refrigeration system oil separator |
US3740963A (en) * | 1972-04-17 | 1973-06-26 | Whirlpool Co | Water control for ice maker |
US4346567A (en) * | 1977-12-14 | 1982-08-31 | Sniader David H | Heat pump control valve |
US4715196A (en) * | 1986-04-11 | 1987-12-29 | Diesel Kiki Co., Ltd. | Oil returning mechanism of evaporator for air conditioner |
US4912937A (en) * | 1988-04-25 | 1990-04-03 | Mitsubishi Denki Kabushiki Kaisha | Air conditioning apparatus |
US5140824A (en) * | 1991-05-28 | 1992-08-25 | Hunt Steven C | Gas hydrate thermal energy storage system |
JP2977046B2 (ja) * | 1992-11-27 | 1999-11-10 | 株式会社ジャパンエナジー | アンモニア冷凍装置、該冷凍装置に用いる作動流体組成物及びアンモニア圧縮機の潤滑方法 |
EP0626443B1 (en) * | 1992-11-27 | 1999-01-27 | Japan Energy Corporation | Ammonia refrigerating unit, working fluid composition to be used in said unit, and lubrication of ammonia compressor |
US5410889A (en) * | 1994-01-14 | 1995-05-02 | Thermo King Corporation | Methods and apparatus for operating a refrigeration system |
AUPM630094A0 (en) * | 1994-06-17 | 1994-07-14 | Refrigerant Monitoring Systems Pty Ltd | Oil level control device |
US5595678A (en) * | 1994-08-30 | 1997-01-21 | Cpi Engineering Services, Inc. | Lubricant composition for ammonia refrigerants used in compression refrigeration systems |
US5561987A (en) * | 1995-05-25 | 1996-10-08 | American Standard Inc. | Falling film evaporator with vapor-liquid separator |
US6274062B1 (en) * | 1996-10-07 | 2001-08-14 | James B. Tieken | Halocarbon/hydrocarbon refrigerant blend |
TW385332B (en) * | 1997-02-27 | 2000-03-21 | Idemitsu Kosan Co | Refrigerating oil composition |
GB2325724B (en) * | 1997-07-04 | 1999-04-21 | Amot Controls Ltd | Device |
JP4564111B2 (ja) * | 1998-09-02 | 2010-10-20 | Jx日鉱日石エネルギー株式会社 | 冷凍機油 |
EP1147166B1 (en) * | 1999-01-25 | 2005-09-21 | MGA Holdings Limited | Process for extracting fixed and mineral oils |
US6516627B2 (en) * | 2001-05-04 | 2003-02-11 | American Standard International Inc. | Flowing pool shell and tube evaporator |
-
2005
- 2005-06-29 WO PCT/JP2005/011930 patent/WO2006003925A1/ja active Application Filing
- 2005-06-29 AU AU2005258567A patent/AU2005258567B2/en not_active Ceased
- 2005-06-29 CN CNA2005800223441A patent/CN1981165A/zh active Pending
- 2005-06-29 JP JP2006528741A patent/JP4475278B2/ja not_active Expired - Fee Related
- 2005-06-29 EP EP05765416.2A patent/EP1780479A4/en not_active Withdrawn
- 2005-06-29 US US11/630,104 patent/US20070245752A1/en not_active Abandoned
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS62276368A (ja) * | 1986-05-23 | 1987-12-01 | 株式会社ボッシュオートモーティブ システム | 空調装置における油戻し機構 |
JPH0755268A (ja) * | 1993-08-09 | 1995-03-03 | Nippondenso Co Ltd | 冷凍装置 |
JPH10160293A (ja) * | 1996-11-29 | 1998-06-19 | Sanyo Electric Co Ltd | 冷凍装置及びアキュームレータ |
JP2003287291A (ja) * | 2002-03-27 | 2003-10-10 | Mitsubishi Electric Corp | 冷凍装置 |
Non-Patent Citations (1)
Title |
---|
See also references of EP1780479A4 * |
Cited By (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2008047988A2 (en) | 2006-10-17 | 2008-04-24 | Lg Electronics Inc. | Water-cooled air conditioner |
EP2054671A2 (en) * | 2006-10-17 | 2009-05-06 | LG Electronics, Inc. | Water-cooled air conditioner |
EP2054671A4 (en) * | 2006-10-17 | 2013-07-31 | Lg Electronics Inc | WATER COOLED AIR CONDITIONER |
JP2009079820A (ja) * | 2007-09-26 | 2009-04-16 | Sanyo Electric Co Ltd | 冷凍サイクル装置 |
JP2011247579A (ja) * | 2011-08-08 | 2011-12-08 | Mitsubishi Electric Corp | プレート式熱交換器及び冷凍空調装置 |
JP2014129948A (ja) * | 2012-12-28 | 2014-07-10 | Daikin Ind Ltd | 空気調和装置及び空気調和装置の施工方法 |
WO2014103173A1 (ja) * | 2012-12-28 | 2014-07-03 | ダイキン工業株式会社 | 空気調和装置及び空気調和装置の施工方法 |
AU2013368096B2 (en) * | 2012-12-28 | 2016-05-05 | Daikin Industries, Ltd. | Air conditioner and air conditioner construction method |
US10184676B2 (en) | 2012-12-28 | 2019-01-22 | Daikin Industries, Ltd. | Air conditioner having simultaneous heating and cooling |
US10443869B2 (en) | 2012-12-28 | 2019-10-15 | Daikin Industries, Ltd. | Air conditioner construction method |
WO2014108997A1 (ja) * | 2013-01-08 | 2014-07-17 | 三菱電機株式会社 | 空気調和装置 |
JP5897154B2 (ja) * | 2013-01-08 | 2016-03-30 | 三菱電機株式会社 | 空気調和装置 |
JPWO2014108997A1 (ja) * | 2013-01-08 | 2017-01-19 | 三菱電機株式会社 | 空気調和装置 |
US10168060B2 (en) | 2013-01-08 | 2019-01-01 | Mitsubishi Electric Corporation | Air-conditioning apparatus |
Also Published As
Publication number | Publication date |
---|---|
JP4475278B2 (ja) | 2010-06-09 |
CN1981165A (zh) | 2007-06-13 |
AU2005258567A1 (en) | 2006-01-12 |
US20070245752A1 (en) | 2007-10-25 |
AU2005258567B2 (en) | 2008-07-03 |
EP1780479A4 (en) | 2013-12-11 |
EP1780479A1 (en) | 2007-05-02 |
JPWO2006003925A1 (ja) | 2008-04-17 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP4475278B2 (ja) | 冷凍装置及び空気調和装置 | |
WO2006003967A1 (ja) | 空気調和装置 | |
AU2005268315B2 (en) | Air conditioner | |
JP5627606B2 (ja) | ヒートポンプシステム | |
JP4715561B2 (ja) | 冷凍装置 | |
CN103221759B (zh) | 空调机 | |
KR20110132393A (ko) | 히트 펌프 시스템 | |
AU2003281797B2 (en) | Refrigeration equipment | |
US7908878B2 (en) | Refrigerating apparatus | |
KR101044464B1 (ko) | 냉동장치 | |
JP5152116B2 (ja) | 冷凍装置 | |
WO2004013550A1 (ja) | 冷凍装置 | |
WO2016207993A1 (ja) | 空気調和装置 | |
KR100825622B1 (ko) | 공기 조화 장치 | |
KR100741252B1 (ko) | 공기 조화 장치 | |
US20230065072A1 (en) | Refrigeration cycle system, heat source unit, and refrigeration cycle apparatus | |
JP2024052350A (ja) | 冷凍サイクル装置 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Kind code of ref document: A1 Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BW BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE EG ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KM KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NA NG NI NO NZ OM PG PH PL PT RO RU SC SD SE SG SK SL SM SY TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW |
|
AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): BW GH GM KE LS MW MZ NA SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LT LU MC NL PL PT RO SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
WWE | Wipo information: entry into national phase |
Ref document number: 2006528741 Country of ref document: JP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 11630104 Country of ref document: US |
|
WWE | Wipo information: entry into national phase |
Ref document number: 200580022344.1 Country of ref document: CN |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
WWW | Wipo information: withdrawn in national office |
Ref document number: DE |
|
WWE | Wipo information: entry into national phase |
Ref document number: 1020077000277 Country of ref document: KR |
|
REEP | Request for entry into the european phase |
Ref document number: 2005765416 Country of ref document: EP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2005765416 Country of ref document: EP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2005258567 Country of ref document: AU |
|
ENP | Entry into the national phase |
Ref document number: 2005258567 Country of ref document: AU Date of ref document: 20050629 Kind code of ref document: A |
|
WWP | Wipo information: published in national office |
Ref document number: 2005258567 Country of ref document: AU |
|
WWP | Wipo information: published in national office |
Ref document number: 1020077000277 Country of ref document: KR |
|
WWP | Wipo information: published in national office |
Ref document number: 2005765416 Country of ref document: EP |
|
WWP | Wipo information: published in national office |
Ref document number: 11630104 Country of ref document: US |