WO2018025614A1 - 冷凍装置 - Google Patents

冷凍装置 Download PDF

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Publication number
WO2018025614A1
WO2018025614A1 PCT/JP2017/025668 JP2017025668W WO2018025614A1 WO 2018025614 A1 WO2018025614 A1 WO 2018025614A1 JP 2017025668 W JP2017025668 W JP 2017025668W WO 2018025614 A1 WO2018025614 A1 WO 2018025614A1
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WO
WIPO (PCT)
Prior art keywords
refrigerant
liquid
heat source
pipe
expansion valve
Prior art date
Application number
PCT/JP2017/025668
Other languages
English (en)
French (fr)
Japanese (ja)
Inventor
東 近藤
Original Assignee
ダイキン工業株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by ダイキン工業株式会社 filed Critical ダイキン工業株式会社
Priority to CN201780047413.7A priority Critical patent/CN109564034B/zh
Priority to EP17836720.7A priority patent/EP3486578B1/de
Publication of WO2018025614A1 publication Critical patent/WO2018025614A1/ja

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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
    • F25B1/00—Compression machines, plants or systems with non-reversible cycle
    • 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
    • F25B47/00—Arrangements for preventing or removing deposits or corrosion, not provided for in another subclass
    • F25B47/02—Defrosting cycles
    • F25B47/022—Defrosting cycles hot gas defrosting
    • F25B47/025—Defrosting cycles hot gas defrosting by reversing the cycle
    • 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
    • F25B41/00—Fluid-circulation arrangements
    • F25B41/20—Disposition of valves, e.g. of on-off valves or flow control valves
    • 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
    • F25B41/00—Fluid-circulation arrangements
    • F25B41/20—Disposition of valves, e.g. of on-off valves or flow control valves
    • F25B41/24—Arrangement of shut-off valves for disconnecting a part of the refrigerant cycle, e.g. an outdoor part
    • 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
    • F25B41/00—Fluid-circulation arrangements
    • F25B41/30—Expansion means; Dispositions thereof
    • F25B41/39—Dispositions with two or more expansion means arranged in series, i.e. multi-stage expansion, on a refrigerant line leading to the same evaporator
    • 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
    • F25B2313/00—Compression machines, plants or systems with reversible cycle not otherwise provided for
    • F25B2313/006—Compression machines, plants or systems with reversible cycle not otherwise provided for two pipes connecting the outdoor side to the indoor side with multiple indoor 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
    • F25B2400/00—General features or devices for refrigeration machines, plants or systems, combined heating and refrigeration systems or heat-pump systems, i.e. not limited to a particular subgroup of F25B
    • F25B2400/13—Economisers
    • 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
    • F25B2600/00—Control issues
    • F25B2600/25—Control of valves
    • F25B2600/2513—Expansion valves
    • 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
    • F25B2600/00—Control issues
    • F25B2600/25—Control of valves
    • F25B2600/2521—On-off valves controlled by pulse signals
    • 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
    • F25B2700/00—Sensing or detecting of parameters; Sensors therefor
    • F25B2700/19—Pressures
    • F25B2700/191—Pressures near an expansion valve
    • 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
    • F25B2700/00—Sensing or detecting of parameters; Sensors therefor
    • F25B2700/21—Temperatures
    • F25B2700/2103—Temperatures near a heat exchanger

Definitions

  • the present invention relates to a refrigeration apparatus that performs a refrigeration cycle by circulating refrigerant in a refrigerant circuit.
  • a refrigerant circuit of a refrigeration apparatus that performs a refrigeration cycle may be provided with an electromagnetic valve to control the flow of the refrigerant.
  • a general solenoid valve switches between an open state and a closed state by intermittently energizing the solenoid.
  • a solenoid valve may be provided in a pipe through which a high-pressure liquid refrigerant flows.
  • the electromagnetic valve When the electromagnetic valve is closed, the flow of high-pressure liquid refrigerant is blocked by the electromagnetic valve.
  • the solenoid valve When the solenoid valve is opened with a large pressure difference between both sides of the solenoid valve, the liquid refrigerant that is substantially incompressible and has a relatively high density suddenly flows to the downstream side of the solenoid valve. This may cause damage to equipment such as piping and expansion valves.
  • Patent Document 1 discloses that a pipe through which a liquid refrigerant flows is heated by an electric heater in order to suppress a liquid hammer phenomenon caused by opening of an electromagnetic valve.
  • a part of the refrigerant in the pipe is evaporated by heating the pipe with an electric heater, and a rapid increase in pressure in the pipe due to the opening of the solenoid valve causes a compressible gas refrigerant to exist in the pipe. It is mitigated by
  • Patent Document 1 requires an electric heater for heating the piping in order to suppress the liquid hammer phenomenon caused by the opening of the electromagnetic valve. For this reason, the number of parts of the refrigeration apparatus increases, leading to an increase in manufacturing cost. Further, while the solenoid valve is closed, it is necessary to continue heating the pipe with the electric heater, which increases the power consumption of the refrigeration apparatus and may increase the running cost of the refrigeration apparatus.
  • the present invention has been made in view of such a point, and an object thereof is to suppress a liquid hammer phenomenon caused by opening of a solenoid valve while suppressing an increase in manufacturing cost and running cost of a refrigeration apparatus.
  • a first aspect of the present disclosure includes a refrigerant circuit (20) in which a heat source side unit (11) and a usage side unit (12) are connected via a liquid side communication pipe (14) and a gas side communication pipe (15). And a refrigeration apparatus that performs a refrigeration cycle by circulating refrigerant in the refrigerant circuit (20).
  • the heat source side unit (11) includes the compressor (31a to 31c), the heat source side heat exchanger (33), and the refrigerant condensed in the heat source side heat exchanger (33). 14) the heat source side expansion valve (38) provided in the pipe (53c) for sending to the above, and the use side unit (12) is used with the use side heat exchanger (61) arranged in series.
  • the heat source side unit (11) and the plurality of usage side units (12) are provided in the refrigerant circuit (20).
  • the refrigerant condensed in the heat source side heat exchanger (33) of the heat source side unit (11) flows into the use side unit (12) through the liquid side communication pipe (14).
  • the refrigerant supplied from the liquid side connection pipe (14) expands when passing through the use side expansion valve (63), and then flows into the use side heat exchanger (61). Evaporate.
  • a cooling target such as air is cooled by the refrigerant.
  • the refrigerant evaporated in the use side heat exchanger (61) of the use side unit (12) flows into the heat source side unit (11) through the gas side connecting pipe (15) and then the compressors (31a to 31c). Inhaled and compressed.
  • the controller (90) performs a predetermined operation when the usage-side unit (12) switches from the cooling state to the dormant state.
  • the operation of the controller (90) will be described.
  • the controller (90) first closes the heat source side expansion valve (38). At this time, since the compressors (31a to 31c) are operating, the refrigerant pressure in the liquid side communication pipe (14) gradually decreases. Thereafter, the controller (90) stops the compressors (31a to 31c) and closes the use side solenoid valve (62). For this reason, when the use side solenoid valve (62) is closed, the density of the refrigerant present on the inflow side of the use side solenoid valve (62) is smaller than when the use side unit (12) is in the cooled state. Get smaller.
  • the controller (90) includes the heat source side expansion valve when the use side unit (12) is switched from the cooling state to the dormant state. Before closing (38), it is configured to perform a preparatory operation for reducing the opening of the heat source side expansion valve (38) so that the refrigerant flowing through the liquid side communication pipe (14) is in a gas-liquid two-phase state. Is.
  • the controller (90) of the second aspect closes the heat source side expansion valve (38) after performing a preparatory operation when the use side unit (12) switches from the cooling state to the dormant state.
  • the controller (90) reduces the opening of the heat source side expansion valve (38) so that the refrigerant flowing through the liquid side communication pipe (14) is in a gas-liquid two-phase state. For this reason, when the heat source side expansion valve (38) is closed and then the use side solenoid valve (62) is closed, both the liquid refrigerant and the gas refrigerant exist in the liquid side communication pipe (14). Become.
  • the heat source side unit (11) measures the pressure of the refrigerant sent from the heat source side expansion valve (38) to the liquid side communication pipe (14).
  • a liquid side temperature sensor (82) for measuring the temperature of the refrigerant sent from the heat source side expansion valve (38) to the liquid side communication pipe (14).
  • the opening of the heat source side expansion valve (38) is such that the measured pressure of the liquid side pressure sensor (87) is less than the refrigerant saturation pressure at the measured temperature of the liquid side temperature sensor (82).
  • the operation of narrowing down is performed as the preparatory operation.
  • the controller (90) performs a preparatory operation using the measured pressure of the liquid side pressure sensor (87) and the measured temperature of the liquid side temperature sensor (82).
  • the controller (90) performs a preparatory operation and the measured pressure of the liquid side pressure sensor (87) is less than the refrigerant saturation pressure at the measured temperature of the liquid side temperature sensor (82)
  • the liquid side communication pipe (14 ) Is in a gas-liquid two-phase state.
  • the controller (90) performs a predetermined operation when the usage-side unit (12) switches from the cooling state to the dormant state. For this reason, when the use side solenoid valve (62) is closed, the density of the refrigerant present on the inflow side of the use side solenoid valve (62) is smaller than when the use side unit (12) is in the cooled state. Get smaller.
  • the refrigerant pressure in the liquid side communication pipe (14) is reduced to thereby reduce the inflow side of the use side solenoid valve (62).
  • the density of the refrigerant existing in can be reduced in advance.
  • the liquid hammer is opened when the use side solenoid valve (62) is opened by suppressing the density of the refrigerant existing on the inflow side of the use side solenoid valve (62) in the closed state.
  • the possibility that the phenomenon occurs can be reduced.
  • the controller (90) of the second aspect closes the heat source side expansion valve (38) after performing a preparatory operation when the use side unit (12) switches from the cooling state to the dormant state. For this reason, when the use side solenoid valve (62) is closed after the heat source side expansion valve (38) is closed, there is a compressible gas refrigerant in the liquid side communication pipe (14). If the gas refrigerant exists in the liquid side communication pipe (14), the pressure fluctuation when the use side solenoid valve (62) is opened is mitigated by the volume change of the gas refrigerant. Therefore, according to this aspect, the presence of the gas refrigerant in the liquid side communication pipe (14) can further reduce the possibility of the liquid hammer phenomenon occurring when the use side solenoid valve (62) is opened.
  • the controller (90) performs the preparatory operation using the measured values of the liquid side pressure sensor (87) and the liquid side temperature sensor (82), so that the liquid side communication pipe (14) The refrigerant flowing through can be reliably brought into a gas-liquid two-phase state.
  • FIG. 1 is a refrigerant circuit diagram illustrating a schematic configuration of the refrigeration apparatus according to the first embodiment.
  • FIG. 2 is a refrigerant circuit diagram showing the refrigeration apparatus during normal operation.
  • FIG. 3 is a block diagram showing the configuration of the main controller.
  • FIG. 4 is a flowchart showing an operation performed by the liquid hammer avoidance control unit of the main controller.
  • FIG. 5 is a refrigerant circuit diagram illustrating a schematic configuration of the refrigeration apparatus of the second embodiment.
  • Embodiment 1 The first embodiment will be described.
  • the refrigeration apparatus (10) of this embodiment is for cooling the interior space of a refrigerator.
  • the refrigeration apparatus (10) includes one heat source side unit (11) and one usage side unit (12).
  • the heat source side unit (11) is a so-called outdoor unit and is installed outdoors.
  • the use side unit (12) is a so-called unit cooler and is installed in the refrigerator.
  • the heat source side unit (11) is provided with a heat source side circuit (21), a heat source side fan (22), and a main controller (90).
  • the use side unit (12) is provided with a use side circuit (23), a use side fan (24), a drain pan (25), and a use side controller (99).
  • the heat source side circuit (21) of the heat source side unit (11) and the usage side circuit (23) of the usage side unit (12) are connected to the liquid side communication pipe (14) and the gas side communication pipe (15 ) To form a refrigerant circuit (20).
  • the refrigerant circuit (20) performs a vapor compression refrigeration cycle by circulating the refrigerant.
  • the heat source side circuit (21) is provided with a liquid closing valve (V1) at the liquid side end and a gas closing valve (V2) at the gas side end.
  • the liquid side connection pipe (14) connects the liquid closing valve (V1) of the heat source side circuit (21) to the liquid side end of the use side circuit (23).
  • the gas side communication pipe (15) connects the gas shut-off valve (V2) of the heat source side circuit (21) to the gas side end of the use side circuit (23).
  • the heat source side circuit (21) includes first to third compressors (31a, 31b, 31c), a four-way switching valve (32), a heat source side heat exchanger (33), and a supercooling heat exchanger (34).
  • the heat source side circuit (21) includes a discharge refrigerant pipe (51), an intake refrigerant pipe (52), a heat source side liquid refrigerant pipe (53), an injection pipe (54), and a first connection pipe (55). ), A second connection pipe (56), and an oil return pipe (57).
  • the number of compressors (31a to 31c) provided in the heat source side unit (11) is merely an example.
  • the first to third compressors (31a, 31b, 31c) are all scroll-type hermetic compressors. Each compressor (31a to 31c) is provided with a suction port, an intermediate port, and a discharge port. The compressors (31a to 31c) compress the refrigerant sucked from the suction port, and discharge the compressed refrigerant from the discharge port.
  • the intermediate ports of the compressors (31a to 31c) are ports for introducing the refrigerant into the compression chamber that is being compressed.
  • the capacity of the first compressor (31a) is variable. Electric power is supplied from an inverter (not shown) to the electric motor of the first compressor (31a). When the output frequency of the inverter is changed, the rotational speed of the first compressor (31a) changes, and the operating capacity of the first compressor (31a) changes. On the other hand, the capacity of each of the second compressor (31b) and the third compressor (31c) is fixed. The second compressor (31b) and the third compressor (31c) rotate at a constant rotational speed.
  • the four-way switching valve (32) has a first state (state indicated by a solid line in FIG. 1) in which the first port and the third port communicate with each other and the second port and the fourth port communicate with each other, It is configured to be switchable to a second state (state indicated by a broken line in FIG. 1) in which the four ports communicate and the second port and the third port communicate.
  • the four-way switching valve (32) has a first port connected to the discharge port of the compressor (31a to 31c) by a discharge refrigerant pipe (51), and a second port connected to the compressor (31a by a suction refrigerant pipe (52). To 31c) intake port.
  • the four-way switching valve (32) has a third port connected to the gas side end of the heat source side heat exchanger (33), and a fourth port connected to the gas closing valve (V2).
  • the discharge refrigerant pipe (51) is composed of the same number (three in this embodiment) of discharge pipes (51a, 51b, 51c) as the compressors (31a to 31c) and one discharge junction pipe (51d). ing.
  • One end of the first discharge pipe (51a) is at the discharge port of the first compressor (31a)
  • one end of the second discharge pipe (51b) is at the discharge port of the second compressor (31b)
  • the third discharge pipe (51c ) Is connected to the discharge port of the third compressor (31c).
  • the other end of each discharge pipe (51a, 51b, 51c) is connected to one end of the discharge junction pipe (51d).
  • the other end of the discharge junction pipe (51d) is connected to the first port of the four-way switching valve (32).
  • the suction refrigerant pipe (52) is composed of the same number (three in this embodiment) of suction pipes (52a, 52b, 52c) as the compressors (31a to 31c) and one suction main pipe (52d). Yes.
  • One end of the first suction pipe (52a) is at the suction port of the first compressor (31a)
  • one end of the second suction pipe (52b) is at the suction port of the second compressor (31b)
  • the third suction pipe (52c ) Is connected to the suction port of the third compressor (31c).
  • the other end of each suction pipe (52a, 52b, 52c) is connected to one end of the suction main pipe (52d).
  • the other end of the suction main pipe (52d) is connected to the second port of the four-way switching valve (32).
  • the heat source side heat exchanger (33) is a cross-fin type fin-and-tube heat exchanger, and exchanges heat between the refrigerant and outdoor air.
  • the liquid source end of the heat source side heat exchanger (33) is connected to the heat source side liquid refrigerant pipe (53), and the gas side end thereof is connected to the third port of the four-way switching valve (32).
  • a heat source side fan (22) for supplying outdoor air to the heat source side heat exchanger (33) is disposed in the vicinity of the heat source side heat exchanger (33).
  • the supercooling heat exchanger (34) is a so-called plate heat exchanger.
  • a plurality of first flow paths (34a) and second flow paths (34b) are formed in the supercooling heat exchanger (34).
  • the supercooling heat exchanger (34) exchanges heat between the refrigerant flowing through the first flow path (34a) and the refrigerant flowing through the second flow path (34b).
  • the heat source side liquid refrigerant pipe (53) is composed of three heat source side liquid pipes (53a, 53b, 53c).
  • the first heat source side liquid pipe (53a) connects the liquid side end of the heat source side heat exchanger (33) and the inlet of the receiver (37).
  • the second heat source side liquid pipe (53b) connects the outlet of the receiver (37) and the inlet of the first flow path (34a) of the supercooling heat exchanger (34).
  • the third heat source side liquid pipe (53c) connects the outlet of the first flow path (34a) of the supercooling heat exchanger (34) and the liquid closing valve (V1).
  • the first heat source side liquid pipe (53a) is provided with a first check valve (CV1).
  • the first check valve (CV1) allows the flow of refrigerant from the heat source side heat exchanger (33) to the receiver (37) and blocks the flow of refrigerant in the reverse direction.
  • the third heat source side liquid pipe (53c) includes a heat source side expansion valve (38) and a second check valve (CV2) in order from the supercooling heat exchanger (34) to the liquid shut-off valve (V1). Is provided.
  • the heat source side expansion valve (38) is an electric expansion valve with variable opening.
  • the second check valve (CV2) allows the refrigerant flow from the supercooling heat exchanger (34) to the liquid closing valve (V1) and blocks the reverse refrigerant flow.
  • the injection pipe (54) is composed of two injection main pipes (54m, 54n) and three injection branch pipes (54a, 54b, 54c).
  • first injection main pipe (54m) is connected between the subcooling heat exchanger (34) and the heat source side expansion valve (38) in the third heat source side liquid pipe (53c), and the other end is subcooling heat exchange.
  • the first injection main pipe (54 m) constitutes a supercooling pipe.
  • a supercooling expansion valve (35) is provided in the first injection main pipe (54m).
  • One end of the second injection main pipe (54n) is connected to the outlet of the second flow path (34b) of the supercooling heat exchanger (34).
  • One end of each injection branch pipe (54a, 54b, 54c) is connected to the other end of the second injection main pipe (54n).
  • the other end of the first injection branch pipe (54a) is connected to the intermediate port of the first compressor (31a), and the other end of the second injection branch pipe (54b) is connected to the intermediate port of the second compressor (31b).
  • the other end of the injection branch pipe (54c) is connected to the intermediate port of the third compressor (31c).
  • Each injection branch pipe (54a to 54c) is provided with one intermediate expansion valve (36a, 36b, 36c).
  • Each of the intermediate expansion valves (36a to 36c) is an electric expansion valve having a variable opening.
  • the first connection pipe (55) is connected between the second check valve (CV2) and the liquid closing valve (V1) in the third heat source side liquid pipe (53c), and the other end is connected to the first heat source side liquid.
  • the pipe (53a) is connected between the first check valve (CV1) and the receiver (37).
  • the first connection pipe (55) is provided with a third check valve (CV3).
  • the third check valve (CV3) allows the flow of refrigerant from one end of the first connection pipe (55) to the other end and blocks the flow of refrigerant in the reverse direction.
  • the second connection pipe (56) is connected between the heat source side expansion valve (38) and the second check valve (CV2) in the third heat source side liquid pipe (53c), and the other end is connected to the first heat source side. It is connected between the heat source side heat exchanger (33) and the first check valve (CV1) in the liquid pipe (53a).
  • the second connection pipe (56) is provided with a fourth check valve (CV4).
  • the fourth check valve (CV4) allows a refrigerant flow from one end of the second connection pipe (56) to the other end, and blocks a reverse refrigerant flow.
  • the oil separator (41) is provided in the discharge junction pipe (51d) of the discharge refrigerant pipe (51). From the compressors (31a to 31c), a gas refrigerant containing mist-like refrigerating machine oil is discharged. The oil separator (41) separates the refrigerating machine oil from the refrigerant discharged from the compressors (31a to 31c).
  • Oil return pipe (57) is a pipe for returning the refrigeration oil from the oil separator (41) to the compressors (31a to 31c). One end of the oil return pipe (57) is connected to the oil separator (41), and the other end is connected to the second injection main pipe (54n).
  • the oil return pipe (57) is provided with a capillary tube (42).
  • the heat source side circuit (21) is provided with a plurality of temperature sensors (81a, 81b, 81c, 82) and a plurality of pressure sensors (85, 86, 87).
  • Each discharge pipe (51a, 51b, 51c) of the discharge refrigerant pipe (51) is provided with one discharge refrigerant temperature sensor (81a, 81b, 81c).
  • the first discharge refrigerant temperature sensor (81a) is attached to the first discharge pipe (51a), and measures the temperature of the refrigerant discharged from the first compressor (31a).
  • the second discharge refrigerant temperature sensor (81b) is attached to the second discharge pipe (51b) and measures the temperature of the refrigerant discharged from the second compressor (31b).
  • the third discharge refrigerant temperature sensor (81c) is attached to the third discharge pipe (51c) and measures the temperature of the refrigerant discharged from the third compressor (31c).
  • the liquid refrigerant temperature sensor (82) is provided in the heat source side liquid refrigerant pipe (53).
  • the liquid refrigerant temperature sensor (82) is attached to the third heat source side liquid pipe (53c) and measures the temperature of the refrigerant flowing through the third heat source side liquid pipe (53c).
  • the liquid refrigerant temperature sensor (82) is a liquid side temperature sensor.
  • the discharge pressure sensor (85) is connected to the discharge junction pipe (51d) of the discharge refrigerant pipe (51), and measures the pressure of the refrigerant discharged from the compressors (31a to 31c).
  • the suction pressure sensor (86) is connected to the suction main pipe (52d) of the suction refrigerant pipe (52) and measures the pressure of the refrigerant sucked into the compressors (31a to 31c).
  • the liquid refrigerant pressure sensor (87) is connected to the third heat source side liquid pipe (53c) of the heat source side liquid refrigerant pipe (53), and measures the pressure of the refrigerant flowing through the third heat source side liquid pipe (53c).
  • the liquid refrigerant pressure sensor (87) is a liquid side pressure sensor.
  • the use side circuit (23) has one use side heat exchanger (61), one drain pan heater (71b), one use side solenoid valve (62), and one use side expansion valve (63). . Further, the use side circuit (23) is provided with one use side liquid refrigerant pipe (71) and one use side gas refrigerant pipe (72).
  • the use side heat exchanger (61) is a fin-and-tube heat exchanger of the cross fin type, and exchanges heat between the refrigerant and the internal air.
  • chamber to the utilization side heat exchanger (61) is arrange
  • the drain pan heater (71b) is constituted by a pipe provided in the drain pan (25) disposed below the use side heat exchanger (61).
  • the drain pan heater (71b) is for warming the drain pan (25) to prevent the drain water from freezing.
  • the use side liquid refrigerant pipe (71) is composed of a first use side liquid pipe (71a) and a second use side liquid pipe (71c).
  • the first usage-side liquid pipe (71a) has one end connected to the liquid-side connecting pipe (14) and the other end connected to one end of the drain pan heater (71b).
  • One end of the first usage side liquid pipe (71a) constitutes the liquid side end of the usage side circuit (23).
  • the second usage side liquid pipe (71c) has one end connected to the other end of the drain pan heater (71b) and the other end connected to the liquid side end of the usage side heat exchanger (61).
  • the use side gas refrigerant pipe (72) has one end connected to the gas side end of the use side heat exchanger (61) and the other end connected to the gas side connecting pipe (15).
  • the other end of the use side gas refrigerant pipe (72) constitutes the gas side end of the use side circuit (23).
  • the use side solenoid valve (62) and the use side expansion valve (63) are provided in the second use side liquid pipe (71c) of the use side liquid refrigerant pipe (71).
  • the usage side expansion valve (63) is disposed between the usage side electromagnetic valve (62) and the usage side heat exchanger (61).
  • the user side solenoid valve (62) switches between an open state and a closed state by intermittently energizing the solenoid.
  • the use side unit (12) When the use side solenoid valve (62) is in the open state, the use side unit (12) is in a cooling state in which the use side heat exchanger (61) functions as an evaporator to cool the internal air.
  • the use side solenoid valve (62) When the use side solenoid valve (62) is in the closed state, the use side unit (12) is in a dormant state in which the refrigerant flow in the use side heat exchanger (61) is blocked.
  • the user side expansion valve (63) is an external pressure equalizing type temperature automatic expansion valve.
  • the temperature sensing cylinder (63a) of the use side expansion valve (63) is attached in the vicinity of one end of the use side gas refrigerant pipe (72) (the end on the use side heat exchanger (61) side).
  • the pressure equalizing pipe (63b) of the use side expansion valve (63) is connected to the vicinity of one end of the use side gas refrigerant pipe (72).
  • the main controller (90) of the heat source side unit (11) includes a compressor controller (91), an intermediate expansion valve controller (92), and a supercooled expansion valve controller (93). And a liquid hammer avoidance control unit (94).
  • the main controller (90) receives the temperature sensors (81a, 81b, 81c, 82) and the pressure sensors (85, 86, 87) provided in the heat source side unit (11). Further, a thermo-off signal is input to the main controller (90) from the use side controller (99) of the use side unit (12). Control operations performed by the main controller (90) will be described later.
  • the use side unit (12) is provided with an intake air temperature sensor (26).
  • the intake air temperature sensor (26) measures the temperature of the internal air before passing through the use side heat exchanger (61).
  • the measured value of the intake air temperature sensor (26) is input to the use side controller (99).
  • the use side controller (99) opens and closes the use side solenoid valve (62) based on the measured value of the intake air temperature sensor (26).
  • the use side controller (99) outputs a thermo-off signal when closing the use side solenoid valve (62). The operation performed by the use side controller (99) will be described later.
  • the four-way switching valve (32) is set to the second state, the use side heat exchanger (61) functions as a condenser, and the heat source side heat exchanger (33) functions as an evaporator. Further, in the defrost operation, the use side fan (24) is stopped.
  • the four-way switching valve (32) is set to the first state.
  • the supercooling expansion valve (35), the intermediate expansion valves (36a, 36b, 36c), and the heat source side expansion valve (38) are controlled by the main controller (90). The operation of the main controller (90) will be described later.
  • the use side solenoid valve (62) of each use side unit (12) is set to an open state.
  • the refrigerant discharged from the compressors (31a to 31c) passes through the oil separator (41) in the discharge refrigerant pipe (51), and then passes through the four-way switching valve (32) to the heat source side heat exchanger (33). In the heat source side heat exchanger (33), it dissipates heat to the outdoor air and condenses.
  • the refrigerant (high-pressure refrigerant) flowing out from the heat source side heat exchanger (33) passes through the first heat source side liquid pipe (53a), the receiver (37), and the second heat source side liquid pipe (53b) in this order, and is supercooled.
  • the refrigerant flows into the first flow path (34a) of the heat exchanger (34) and is cooled by the refrigerant flowing through the second flow path (34b) of the supercooling heat exchanger (34).
  • the remainder passes through the heat source side expansion valve (38) and the liquid closing valve (V1) in this order, and then flows into the liquid side connection pipe (14).
  • the refrigerant that has flowed into the liquid side communication pipe (14) is introduced into the use side circuit (23) of the use side unit (12).
  • the usage side circuit (23) the refrigerant flowing into the first usage side liquid pipe (71a) passes through the drain pan heater (71b) and then passes through the second usage side liquid pipe (71c) to the usage side solenoid valve (62). Flow into.
  • the refrigerant that has passed through the use-side electromagnetic valve (62) expands into a gas-liquid two-phase state when passing through the use-side expansion valve (63), and then flows into the use-side heat exchanger (61).
  • the use side heat exchanger (61) the refrigerant that has flowed in absorbs heat from the inside air and evaporates, and the inside air is cooled.
  • the use side unit (12) sends the internal air cooled by the use side heat exchanger (61) back to the internal space.
  • the refrigerant evaporated in the use side heat exchanger (61) flows into the gas side communication pipe (15) through the use side gas refrigerant pipe (72).
  • the refrigerant that flows into the gas side communication pipe (15) from each use side circuit (23) flows into the heat source side circuit (21) after merging, and passes through the gas shut-off valve (V2) and the four-way switching valve (32) in order. Later, the refrigerant is sucked into the compressors (31a to 31c) through the suction refrigerant pipe (52).
  • the refrigerant that has flowed into the first injection main pipe (54m) expands into a gas-liquid two-phase state when passing through the supercooling expansion valve (35), and then enters the second phase of the supercooling heat exchanger (34).
  • the refrigerant flows into the channel (34b), absorbs heat from the refrigerant (high-pressure refrigerant) flowing through the first channel (34a) of the supercooling heat exchanger (34), and evaporates.
  • the refrigerant that has flowed into the second injection main pipe (54n) from the second flow path (34b) of the supercooling heat exchanger (34) is introduced into the intermediate ports of the compressors (31a to 31c).
  • the usage-side controller (99) opens and closes the usage-side electromagnetic valve (62) based on the measured value of the intake air temperature sensor (26). The operation of the use side controller (99) will be described.
  • the use side controller (99) sets the use side electromagnetic so that the measured value Tr of the intake air temperature sensor (26) is in the range of the set temperature Tr_set ⁇ 1 ° C. (that is, Tr_set-1 ⁇ Tr ⁇ Tr_set + 1). Operate the valve (62).
  • the use side solenoid valve (62) is in an open state.
  • the use side unit (12) In a state where the use side solenoid valve (62) is open, the use side unit (12) is in a cooled state. That is, the refrigerant flows into the use side heat exchanger (61) and evaporates, and the internal air is cooled in the use side heat exchanger (61).
  • the temperature in the cabinet that is, the measured value Tr of the intake air temperature sensor (26)
  • Tr_set-1 that is, Tr ⁇ Tr_set-1
  • the use side controller (99) opens the use side solenoid valve (62). Switch from state to closed state.
  • the usage-side controller (99) When the usage-side controller (99) switches the usage-side solenoid valve (62) from the open state to the closed state, the usage-side controller (99) generates a thermo-off signal indicating that the usage-side unit (12) has entered the dormant state. ).
  • the use side unit (12) In the state where the use side solenoid valve (62) is closed, the use side unit (12) is in a dormant state. That is, the refrigerant flow in the use side heat exchanger (61) is blocked, and the internal air is not cooled in the use side heat exchanger (61).
  • the temperature in the cabinet that is, the measured value Tr of the intake air temperature sensor (26)
  • Tr_set + 1 that is, Tr_set + 1 ⁇ Tr
  • the use side controller (99) opens the use side solenoid valve (62) from the closed state to the open state. Switch to.
  • the use-side controller (99) is configured to be able to receive the open hold command output from the main controller (90).
  • the opening hold command will be described later.
  • the use side controller (99) holds the use side solenoid valve (62) in the open state until the open hold command is canceled.
  • the usage-side controller (99) may determine that the measured value Tr of the intake air temperature sensor (26) is less than Tr_set-1. The user side solenoid valve (62) is kept open.
  • the main controller (90) includes the compressor control unit (91), the intermediate expansion valve control unit (92), the supercooling expansion valve control unit (93), and the liquid hammer avoidance control unit (94 ).
  • the compressor control unit (91), the intermediate expansion valve control unit (92), the supercooling expansion valve control unit (93), and the liquid hammer avoidance control unit will be described.
  • the main controller (90) also operates the four-way switching valve (32) for switching between normal operation and defrost operation, and controls the rotational speed of the heat source side fan (22).
  • the compressor control unit (91) adjusts the operating capacity of the first compressor (31a) and switches between operation and stop of the second compressor (31b) and the third compressor (31c).
  • the measurement value in (86) is set to a predetermined target pressure.
  • the compressor control unit (91) performs an operation of increasing the operating capacity of the compressors (31a to 31c). That is, in this case, the compressor controller (91) gradually increases the output frequency of the inverter to increase the operating capacity of the first compressor (31a), and the second compressor (31b) and the third compressor. (31c) The operation of starting the stopped one is performed.
  • the compressor control unit (91) performs an operation of reducing the operating capacity of the compressors (31a to 31c). That is, in this case, the compressor control unit (91) gradually decreases the output frequency of the inverter to reduce the operating capacity of the first compressor (31a), and the second compressor (31b) and the third compressor. (31c) The operation
  • the intermediate expansion valve control unit (92) adjusts the opening degree of each intermediate expansion valve (36a to 36c).
  • the intermediate expansion valve controller (92) adjusts the opening of the first intermediate expansion valve (36a) based on the measured values of the first discharge refrigerant temperature sensor (81a) and the discharge pressure sensor (85),
  • the opening degree of the second intermediate expansion valve (36b) is adjusted based on the measured values of the discharge refrigerant temperature sensor (81b) and the discharge pressure sensor (85), and the third discharge refrigerant temperature sensor (81c) and the discharge pressure sensor (85 ) To adjust the opening of the third intermediate expansion valve (36c).
  • the intermediate expansion valve control unit (92) adjusts the opening degree of the first intermediate expansion valve (36a)
  • the intermediate expansion valve control unit (92) performs the same opening degree adjusting operation on the second intermediate expansion valve (36b) and the third intermediate expansion valve (36c).
  • the intermediate expansion valve control unit (92) reduces the measured value of the first discharged refrigerant temperature sensor (81a) The operation of increasing the opening of the first intermediate expansion valve (36a) is performed.
  • the intermediate expansion valve control unit (92) determines the degree of superheat of the refrigerant discharged from the first compressor (31a). Is adjusted to an opening degree of the first intermediate expansion valve (36a) so that a predetermined target discharge superheat degree is obtained. Specifically, the intermediate expansion valve control unit (92) determines the superheat degree of the refrigerant discharged from the first compressor (31a), the measured value of the first discharge refrigerant temperature sensor (81a), and the discharge pressure sensor (85). It calculates using the measured value of.
  • the intermediate expansion valve controller (92) increases the opening of the first intermediate expansion valve (36a) when the calculated superheat value exceeds the target discharge superheat value, and the calculated superheat value is the target discharge value. When the degree of superheat is lower, the opening degree of the first intermediate expansion valve (36a) is reduced.
  • the intermediate expansion valve controller (92) adjusts the opening of the intermediate expansion valve (36a to 36c) when the compressor (31a to 31c) corresponding to the intermediate expansion valve (36a to 36c) is operating.
  • the intermediate expansion valves (36a to 36c) are held in a fully closed state. That is, the intermediate expansion valve control unit (92) adjusts the opening of the second intermediate expansion valve (36b) during operation of the second compressor (31b), and adjusts the opening of the second compressor (31b) while the second compressor (31b) is stopped. 2 Hold the intermediate expansion valve (36b) in a fully closed state.
  • the intermediate expansion valve control unit (92) adjusts the opening of the third intermediate expansion valve (36c) during operation of the third compressor (31c), and adjusts the opening of the third compressor (31c) while the third compressor (31c) is stopped. 3 Hold the intermediate expansion valve (36c) in the fully closed state.
  • the supercooling expansion valve controller (93) opens the supercooling expansion valve (35) according to the temperature of the liquid refrigerant sent from the heat source side unit (11) to the liquid side communication pipe (14) during normal operation. Adjust.
  • the temperature of the liquid refrigerant sent out from the heat source side unit (11) to the liquid side communication pipe (14) during normal operation is substantially equal to the measured value of the liquid refrigerant temperature sensor (82). Therefore, the supercooling expansion valve controller (93) opens the supercooling expansion valve (35) so that the measured value of the liquid refrigerant temperature sensor (82) becomes a predetermined target liquid refrigerant temperature (for example, 20 ° C.). Adjust the degree.
  • the degree of supercooling of the liquid refrigerant sent from the heat source side unit (11) to the liquid side connection pipe (14) is approximately 0. It is about 20 ° C to 20 ° C.
  • the supercooling expansion valve controller (93) reduces the degree of opening of the supercooling expansion valve (35) and The temperature of the refrigerant sent from the cooling expansion valve (35) to the second flow path (34b) of the supercooling heat exchanger (34) is lowered.
  • the supercooling expansion valve control unit (93) increases the degree of opening of the supercooling expansion valve (35) and performs supercooling expansion. The temperature of the refrigerant sent from the valve (35) to the second flow path (34b) of the supercooling heat exchanger (34) is increased.
  • the liquid hammer avoidance control unit (94) performs liquid hammer avoidance control. This liquid hammer avoidance control is performed when the usage-side unit (12) switches from the cooling state to the resting state.
  • liquid hammer avoidance control is demonstrated, referring the flowchart of FIG.
  • step ST1 the liquid hammer avoidance control unit (94) determines whether or not a thermo-off signal is received from the use side unit (12). When the thermo-off signal is not received, no liquid hammer is generated, so the liquid hammer avoidance control unit (94) ends the liquid hammer avoidance control. On the other hand, when the thermo-off signal is received, the liquid hammer avoidance control unit (94) proceeds to step ST2.
  • step ST2 the liquid hammer avoidance control unit (94) outputs an open holding command to the use side controller (99).
  • This open hold command is a command signal for causing the use side controller (99) to hold the use side solenoid valve (62) in the open state.
  • the use-side controller (99) that has received the open hold command holds the use-side solenoid valve (62) in the open state until the open hold command is canceled.
  • the liquid hammer avoidance control unit (94) performs a preparation operation.
  • This preparatory operation is an operation to reduce the opening of the heat source side expansion valve (38) so that the refrigerant flowing through the liquid side communication pipe (14) is in a gas-liquid two-phase state before closing the heat source side expansion valve (38). It is.
  • the operation from step ST3 to step ST5 corresponds to the preparation operation.
  • the liquid hammer avoidance control unit (94) sets a target pressure Ps_t that is a target value of the refrigerant pressure in the liquid side communication pipe (14). Specifically, the liquid hammer avoidance control unit (94) reads the measurement value TL of the liquid refrigerant temperature sensor (82). The liquid hammer avoidance control unit (94) calculates the saturation pressure of the refrigerant at the measurement value TL using the read measurement value TL and the physical properties of the refrigerant, and sets the saturation pressure value as the target pressure Ps_t.
  • the liquid hammer avoidance control unit (94) reduces the opening of the heat source side expansion valve (38) so that the measured value Ps of the liquid refrigerant pressure sensor (87) becomes the target pressure Ps_t.
  • the amount of reduction of the opening degree of the heat source side expansion valve (38) in step ST4 may be a predetermined constant value or adjusted according to the measured value Ps of the liquid refrigerant pressure sensor (87) and the target pressure Ps_t. It may be a value.
  • the liquid hammer avoidance control unit (94) reads the measurement value Ps of the liquid refrigerant pressure sensor (87), and compares the read measurement value Ps with the target pressure Ps_t. When the measured value Ps is equal to or higher than the target pressure Ps_t (Ps ⁇ Ps_t), the liquid hammer avoidance control unit (94) returns to step ST4 and further reduces the opening degree of the heat source side expansion valve (38). On the other hand, when the measured value Ps is less than the target pressure Ps_t (Ps ⁇ Ps_t), it can be determined that the refrigerant flowing in the liquid side communication pipe (14) is in a gas-liquid two-phase state. Therefore, in this case, the liquid hammer avoidance control unit (94) proceeds to step ST6 and fully closes the heat source side expansion valve (38).
  • the liquid hammer avoidance control unit (94) reads the measured value LP of the suction pressure sensor (86), and compares the read measured value LP with the lower limit pressure LP_min stored in advance. When the measured value LP is equal to or higher than the lower limit pressure LP_min (LP ⁇ LP_min), the liquid hammer avoidance control unit (94) stands by as it is. On the other hand, when the measured value LP is less than the lower limit pressure LP_min (LP ⁇ LP_min), the liquid hammer avoidance control unit (94) proceeds to step ST8 and stops the compressors (31a to 31c).
  • the liquid hammer avoidance control unit (94) cancels the open holding command output in step ST2, and ends the liquid hammer avoidance control.
  • the use-side controller (99) of the use-side unit (12) has output the thermo-off signal, the measured value Tr of the intake air temperature sensor (26) has already fallen below Tr_set-1. For this reason, when the liquid hammer avoidance control unit (94) cancels the release holding command, the usage side controller (99) of the usage side unit (12) closes the usage side electromagnetic valve (62).
  • the liquid hammer avoidance control unit (94) of the main controller (90) performs the liquid hammer avoidance control.
  • the heat source side expansion valve (38) is fully closed, and the measured value LP of the suction pressure sensor (86) is the lower limit.
  • the pressure falls below the pressure LP_min, the compressors (31a to 31c) are stopped, and further, the release holding command is released.
  • the refrigerant pressure in the liquid side communication pipe (14) is sufficiently lowered at the time when the use side controller (99) closes the use side solenoid valve (62) after the release holding command is released. For this reason, when the use side solenoid valve (62) is closed, the density of the refrigerant present on the inflow side of the use side solenoid valve (62) is smaller than when the use side unit (12) is in the cooled state. Get smaller. Therefore, according to the present embodiment, the density of the refrigerant existing on the inflow side of the closed use side solenoid valve (62) is suppressed to a low level when the use side solenoid valve (62) is opened. The possibility of the hammer phenomenon can be reduced.
  • the liquid hammer avoidance control unit (94) of the present embodiment fully closes the heat source side expansion valve (38) after performing a preparatory operation when the use side unit (12) switches from the cooling state to the resting state. State.
  • the liquid hammer avoidance control unit (94) throttles the opening of the heat source side expansion valve (38) so that the refrigerant flowing through the liquid side communication pipe (14) is in a gas-liquid two-phase state, and then the heat source side expansion.
  • the valve (38) is fully closed.
  • both liquid refrigerant and gas refrigerant exist in the liquid side communication pipe (14). If the gas refrigerant exists in the liquid side communication pipe (14), the pressure fluctuation when the use side solenoid valve (62) is opened is mitigated by the volume change of the gas refrigerant. Therefore, according to the present embodiment, the presence of the gas refrigerant in the liquid side communication pipe (14) can further reduce the possibility of the liquid hammer phenomenon occurring when the use side solenoid valve (62) is opened.
  • Embodiment 2 ⁇ Embodiment 2 >> Embodiment 2 will be described.
  • the difference between the refrigeration apparatus (10) of the present embodiment and the refrigeration apparatus (10) of the first embodiment will be described.
  • the refrigeration apparatus (10) of this embodiment includes a plurality of (two in this embodiment) usage-side units (12A, 12B).
  • Each use side unit (12) is a so-called unit cooler.
  • Two user-side units (12A, 12B) shown in FIG. 5 are installed in a refrigerator (that is, one space).
  • the number of usage-side units (12) is merely an example.
  • the liquid side communication pipe (14) is connected to the liquid side end of the usage side circuit (23) of each usage side unit (12A, 12B), and each usage side unit (
  • the gas side connecting pipe (15) is connected to the gas side end of the use side circuit (23) of 12A, 12B).
  • only the first usage side unit (12A) includes the usage side controller (99) and the intake air temperature sensor (26).
  • This use side controller (99) controls the use side solenoid valve (62) of the first use side unit (12A) and the use side solenoid valve (62) of the second use side unit (12B).
  • Tr_set-1 that is, Tr ⁇ Tr_set-1
  • Tr_set-1 that is, Tr ⁇ Tr_set-1
  • the usage-side controller (99) causes each usage-side unit (12A, 12B) Switch the use side solenoid valve (62) from open to closed.
  • the two usage-side units (12A, 12B) are simultaneously switched from the cooling state to the resting state.
  • Tr_set + 1 that is, Tr> Tr_set + 1
  • Tr_set + 1 that is, Tr> Tr_set + 1
  • the use side controller (99) uses the use side electromagnetics of the use side units (12A, 12B). Switch the valve (62) from closed to open. As a result, the two usage-side units (12A, 12B) are simultaneously switched from the resting state to the cooling state.
  • the main controller (90) of the refrigeration apparatus (10) of the present embodiment also includes a liquid hammer avoidance control unit (94). And a liquid hammer avoidance control part (94) performs the liquid hammer avoidance control shown in FIG.
  • the present invention is useful for a refrigeration apparatus that performs a refrigeration cycle by circulating refrigerant in a refrigerant circuit.
  • Refrigeration equipment 11
  • Heat source side unit 12
  • User side unit 14
  • Liquid side connection pipe 15
  • Gas side connection pipe 20
  • Refrigerant circuit 31a 1st compressor 31b 2nd compressor 31c 3rd compressor 33
  • Heat source side heat exchanger 34
  • Supercooling heat exchange 35
  • Heat source side expansion valve 53c
  • Third heat source side liquid pipe (pipe) 61
  • User side heat exchanger 63
  • User side expansion valve 62
  • User side solenoid valve 82
  • Liquid refrigerant temperature sensor liquid side temperature sensor
  • Liquid refrigerant pressure sensor Liquid refrigerant pressure sensor (Liquid side pressure sensor) 90 controller

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Air Conditioning Control Device (AREA)
  • Compression-Type Refrigeration Machines With Reversible Cycles (AREA)
  • Devices That Are Associated With Refrigeration Equipment (AREA)
PCT/JP2017/025668 2016-08-04 2017-07-14 冷凍装置 WO2018025614A1 (ja)

Priority Applications (2)

Application Number Priority Date Filing Date Title
CN201780047413.7A CN109564034B (zh) 2016-08-04 2017-07-14 制冷装置
EP17836720.7A EP3486578B1 (de) 2016-08-04 2017-07-14 Kühleinrichtung

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JP2016-153801 2016-08-04
JP2016153801A JP6323508B2 (ja) 2016-08-04 2016-08-04 冷凍装置

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Publication number Priority date Publication date Assignee Title
JPH02187567A (ja) * 1989-01-13 1990-07-23 Mitsubishi Electric Corp 冷凍装置
JPH08233379A (ja) * 1995-02-24 1996-09-13 Mitsubishi Heavy Ind Ltd 冷凍装置
JPH10220888A (ja) * 1997-02-06 1998-08-21 Denso Corp 冷凍サイクル
JPH11325654A (ja) 1998-05-15 1999-11-26 Mitsubishi Electric Corp 冷凍装置
JP2003130482A (ja) * 2001-10-26 2003-05-08 Mitsubishi Electric Corp 空気調和装置
JP2006317116A (ja) * 2005-05-16 2006-11-24 Denso Corp エジェクタサイクル
JP2013053813A (ja) * 2011-09-05 2013-03-21 Mitsubishi Electric Corp 冷却装置

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Publication number Priority date Publication date Assignee Title
EP0874202B1 (de) * 1997-04-22 2003-03-05 Denso Corporation Mit einem elektromagnetischen Ventil vereinigtes Entspannungsventil und dieses verwendender Kältekreislauf
CN100562695C (zh) * 2004-08-02 2009-11-25 大金工业株式会社 制冷装置
JP4389927B2 (ja) * 2006-12-04 2009-12-24 ダイキン工業株式会社 空気調和装置
JP4888583B2 (ja) * 2010-05-31 2012-02-29 ダイキン工業株式会社 冷凍装置
JP2014070830A (ja) * 2012-09-28 2014-04-21 Daikin Ind Ltd 冷凍装置

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02187567A (ja) * 1989-01-13 1990-07-23 Mitsubishi Electric Corp 冷凍装置
JPH08233379A (ja) * 1995-02-24 1996-09-13 Mitsubishi Heavy Ind Ltd 冷凍装置
JPH10220888A (ja) * 1997-02-06 1998-08-21 Denso Corp 冷凍サイクル
JPH11325654A (ja) 1998-05-15 1999-11-26 Mitsubishi Electric Corp 冷凍装置
JP2003130482A (ja) * 2001-10-26 2003-05-08 Mitsubishi Electric Corp 空気調和装置
JP2006317116A (ja) * 2005-05-16 2006-11-24 Denso Corp エジェクタサイクル
JP2013053813A (ja) * 2011-09-05 2013-03-21 Mitsubishi Electric Corp 冷却装置

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Title
See also references of EP3486578A4

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CN109564034B (zh) 2020-04-07
JP6323508B2 (ja) 2018-05-16
EP3486578A1 (de) 2019-05-22
EP3486578A4 (de) 2020-04-08
EP3486578B1 (de) 2023-06-14
JP2018021723A (ja) 2018-02-08
CN109564034A (zh) 2019-04-02

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