JP2005282887A - Air conditioning refrigeration device and control method of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air conditioning refrigeration device and a control method of the same capable of preventing the stop of refrigerant flow even when a refrigerating machine is failed. <P>SOLUTION: This air conditioning refrigerating device 1 is provided with bypass passages 70, 80 for guiding the refrigerant from evaporators 43, 49 to an inlet of a cascade heat exchanger without passing through a failed compressor 37 (or 54) but through the other compressor 54 (or 37), in a case when a refrigerating system (compressor 37) or a freezing system (compressor 54) is failed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an air-conditioning refrigeration apparatus and a method for controlling the air-conditioning refrigeration apparatus for cooling a cooling storage facility in a store, for example.

Conventionally, the inside (indoor) of a store such as a convenience store is air-conditioned and air-conditioned by an air conditioner. In addition, in the store, there are open showcases for refrigeration or refrigeration for displaying and selling products, and showcases (cooling storage facilities) with doors, and these are cooled by the refrigerator (for example, Patent Document 1).
JP 2002-174470 A

  By the way, when the refrigerator which cools the cooling storage facility fails, there is a problem that the flow of the refrigerant stops and the cooling of the cooling storage facility stops completely.

  This invention is made | formed in view of the situation mentioned above, and provides the control method of an air-conditioning refrigerating apparatus which can prevent the flow of a refrigerant | coolant from stopping even if a refrigerator fails. It is aimed.

In order to solve the above-mentioned problems, the present invention includes a compressor, a heat source side heat exchanger, and a use side heat exchanger, and an air conditioning system unit that performs indoor air conditioning by the use side heat exchanger, and 2 connected in series. A refrigeration system unit including a cooling compressor, a condenser, a refrigeration evaporator, and a refrigeration evaporator for cooling the inside of the cooling storage facility by the evaporator, and for air conditioning on the low pressure side of the air conditioning system unit In the air-conditioning refrigeration apparatus that is thermally coupled with a cascade heat exchanger to which the refrigerant and the cooling refrigerant on the high-pressure side of the refrigeration system unit are supplied,
When one of the two cooling compressors fails, the cooling refrigerant from the evaporator passes through the other cooling compressor without passing through the failed cooling compressor. And a bypass path forming means for forming a bypass path leading to the inlet of the cascade heat exchanger. According to this configuration, when one of the two cooling compressors breaks down, the cooling refrigerant from the evaporator is transferred to the other cooling compressor without passing through the failed cooling compressor. By forming a bypass path that leads to the inlet of the cascade heat exchanger via the, it is possible to prevent the flow of the cooling refrigerant from stopping even if the cooling compressor fails.

  In the above configuration, the two cooling compressors are a refrigeration compressor and a refrigeration amplification compressor, and the bypass path forming means has failed in either one of the two cooling compressors. A first bypass path that connects a refrigerant path between the outlet of the refrigeration evaporator and the compressor for refrigeration amplification, and a refrigerant path on the outlet side of the refrigeration evaporator; It is preferable to form a second bypass path that connects the refrigerant path on the discharge side of the compressor and the refrigerant path on the inlet side of the cascade heat exchanger.

  In addition, the present invention includes an air conditioning system unit that includes a compressor, a heat source side heat exchanger, and a usage side heat exchanger and performs indoor air conditioning by the usage side heat exchanger, and two cooling compression units connected in series. A refrigeration system section that includes an air conditioner, a condenser, a refrigeration evaporator, and a refrigeration evaporator, wherein the evaporator cools the interior of the cooling storage facility, and the low-pressure air conditioning refrigerant and the refrigeration system of the air conditioning system section In the control method of an air-conditioning refrigeration apparatus that includes a cascade heat exchanger that is supplied with a cooling refrigerant on the high-pressure side of the unit and that is thermally connected, when one of the two cooling compressors fails A first bypass path connecting a refrigerant path between the outlet of the refrigeration evaporator and the compressor for refrigeration amplification, and a refrigerant path on the outlet side of the refrigeration evaporator; and the compressor for refrigeration amplification Refrigerant path on the discharge side and refrigerant on the inlet side of the cascade heat exchanger And forming a second bypass path connecting the path with the cooling refrigerant from the evaporator via the other cooling compressor without passing through the failed cooling compressor. It leads to the inlet of a cascade heat exchanger.

  The air-conditioning refrigeration apparatus of the present invention forms a bypass path that guides the cooling refrigerant from the evaporator to the inlet of the cascade heat exchanger without going through the failed cooling compressor when the cooling compressor fails Therefore, it is possible to prevent the flow of the cooling refrigerant from stopping even if the cooling compressor fails.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram showing a system configuration including a refrigerant circuit of an air conditioning refrigeration apparatus 1 according to an embodiment of the present invention. The refrigeration system 1 realizes, for example, air conditioning in a room 2 (inside a store) of a convenience store and cooling of the refrigerator case 3 and the refrigerator case 4 as cooling storage equipment installed therein.

  The refrigerated case 3 and the refrigerated case 4 are open showcases whose front and upper surfaces are open, as well as showcases whose openings are closed with a transparent glass door, and the inside of the refrigerator case 3 is refrigerated ( + 3 ° C. to + 10 ° C.), chilled foods such as beverages and sandwiches are displayed, and the inside of the freezing case 4 is cooled to a freezing temperature (−20 ° C. to −10 ° C.). Etc. are displayed.

  This air-conditioning refrigeration apparatus 1 includes an air conditioner (air-conditioning system unit) 6 that performs air-conditioning of a room 2 and a cooling device (cooling system) that cools a refrigerator case 3 and a refrigeration case 4 (cooling storage facility) in the room 2. The air conditioner 6 includes an air conditioning refrigerant circuit 7 extending between a plurality of indoor units 11 installed on the ceiling or the like of the room 2 and an outdoor unit 12 installed outside the store. It is composed of piping.

  The air conditioning refrigerant circuit 7 includes two compressors (rotary compressors) 13A (frequency control operation by an inverter) and 13B (constant speed operation) installed in an exterior case of the outdoor unit 12, a check valve 5A, 5B, 5C, 5D, the oil separator 10, the four-way valve 14, the heat source side heat exchanger 16, the expansion valves (decompression means comprising electric expansion valves) 17, 18, 19, the cascade heat exchanger 21, A system configuration is made up of a check valve 22, an accumulator 23, and the like, and a use side heat exchanger 27 installed on the indoor unit 11 side (air conditioning system).

  Reference numeral 26 denotes an outdoor unit controller (a controller that constitutes an operation control means, and is constituted by a general-purpose microcomputer) for controlling equipment on the outdoor unit 12 side of the air conditioner 6 based on temperature and pressure. The outdoor unit 12 is provided. Reference numeral 24 denotes a blower for ventilating the outside air to the heat source side heat exchanger 16 and is provided at a position corresponding to the heat source side heat exchanger 16 in the outdoor unit 12. 28 is an indoor unit controller for controlling the equipment on the indoor unit 11 side of the air conditioner 6 based on temperature and pressure (a controller that constitutes an operation control means, which is constituted by a general-purpose microcomputer), It is provided in the indoor unit 11.

  Here, a remote operation device (remote control (commonly called remote control)) 29 for operating the air conditioner 6 is installed in the room 2. The remote control device 29 includes a display unit including various liquid crystal panels for displaying various types of information and various controls, and inputs instructions such as the set temperature of the room 2 from the user through the operation of the controls, and the indoor unit controller In addition to notifying the indoor unit controller 28 of various instructions input to the user through communication with the unit 28, the operation information (operation state (cooling operation or heating operation etc.)) of the air conditioner 6 and the like are displayed. To display. Reference numeral 15 denotes a blower for passing the air in the room 2 (in-store air) through the use side heat exchanger 27, and is provided at a position corresponding to the use side heat exchanger 27 in the indoor unit 11.

  The compressors 13A and 13B are connected in parallel to each other, and the discharge sides of the compressors 13A and 13B are joined via check valves 5A and 5B, respectively, and connected to one inlet of the four-way valve 14 ( Each check valve 5A, 5B has a four-way valve 14 direction as a forward direction). One outlet of the four-way valve 14 is connected to the inlet of the heat source side heat exchanger 16. The heat source side heat exchanger 16 includes an inlet side 16A having a relatively small flow resistance composed of a large number of parallel pipes and an outlet side 16B in which these are aggregated into a small number of parallel pipes or a single pipe. The outlet on the outlet side 16B of the heat source side heat exchanger 16 is connected to the inlet of an expansion valve (use side heat exchanger pressure reducing valve) 18 via a check valve 5C and an expansion valve 17 connected in parallel. The outlet of the expansion valve 18 is diverted across the indoor unit 11 and connected to the inlet of the use side heat exchanger 27.

  The outlet of the use side heat exchanger 27 crosses the outdoor unit 12 and is connected to the other inlet of the four-way valve 14, and the other outlet of the four-way valve 14 is connected to the accumulator 23 via the check valve 5D. And the exit of this accumulator 23 is connected to the suction side of compressor 13A, 13B. The check valve 5D has a forward direction on the accumulator 23 side.

  The piping between the expansion valves 17 and 18 is connected to the inlet of the expansion valve 19, and the outlet of the expansion valve 19 is connected to the inlet of the air conditioning side passage 21 </ b> A of the cascade heat exchanger 21. The outlet of the air conditioning side passage 21A of the cascade heat exchanger 21 is connected to the suction side of the compressors 13A and 13B via an accumulator 23.

  On the other hand, in the cooling device 8, a refrigerant circuit 9 for cooling storage equipment is formed between the outdoor unit 12 and the refrigeration case 3 and the refrigeration case 4 installed in the room 2 (inside the store). The refrigerant circuit 9 for cooling storage equipment includes a refrigeration compressor (scroll compressor) 37, a condenser (heat exchanger) 38, and four-way valves 39, 41, 42 installed in the outer case of the outdoor unit 12. (By-pass valve 42 and refrigerator controller 32 constitute bypass path forming means), oil separator 31, receiver tank 36, refrigerating evaporator 43 for cooling the inside of refrigerating case 3, expansion valve ( Electric expansion valve) 44, electromagnetic valves 46 and 47, a freezing evaporator 49 for cooling the inside of the refrigeration case 4, an expansion valve (electric expansion valve) 51, an electromagnetic valve 52, a compressor for refrigeration amplification (rotary compressor) ) 54, check valve 30, oil separator 45, and the like.

  Reference numeral 32 denotes a refrigerator controller (a controller that constitutes a cooling system, and is constituted by a general-purpose microcomputer) that controls equipment on the outdoor unit 12 side of the cooling device 8 based on temperature and pressure. Is provided. The refrigerator controller 32 also functions as a failure detection unit that detects a failure of the compressor 37 and the like, and when a failure is detected, notifies the main controller 56 to that effect.

  Reference numeral 35 denotes a blower for passing outside air through the condenser 38, and is provided at a position corresponding to the condenser 38 of the outdoor unit 12. Reference numeral 50 denotes a refrigeration case controller (a controller constituting the cooling storage facility system control means, which is constituted by a general-purpose microcomputer) that controls equipment on the refrigeration case 3 side based on temperature and pressure. 3 is provided. Further, 55 is a refrigeration case controller (a controller constituting a cooling storage facility system control means, which is constituted by a general-purpose microcomputer) that controls equipment on the side of the refrigeration case 4 based on temperature and pressure. 4 is provided.

  Reference numeral 20 denotes a blower for ventilating the cold air in the refrigerator case 3 to the refrigerator 43 for cooling, and is provided at a position corresponding to each evaporator 43 in the refrigerator case 3. Reference numeral 25 denotes a blower for passing cold air in the refrigerator case 4 through the freezer evaporator 49, and is provided at a position corresponding to the freezer evaporator 49 in the freezer case 4.

  The discharge side of the compressor 37 is connected to one inlet of the four-way valve 39 via the oil separator 31, and one outlet of the four-way valve 39 is connected to the inlet of the condenser 38. The condenser 38 includes an inlet side 38A having a relatively small flow resistance composed of a large number of parallel pipes, and an outlet side 38B in which these are aggregated into a small number of parallel pipes or a single pipe. The outlet on the outlet side 38B of the condenser 38 is connected to the inlet of the receiver tank 36, and the outlet of the receiver tank 36 is connected to one inlet of the four-way valve 41. That is, the receiver tank 36 is connected to the refrigerant downstream side of the condenser 38.

  One outlet of the four-way valve 41 is connected to the inlet of the case side passage 21 </ b> B of the cascade heat exchanger 21. The cascade heat exchanger 21 exchanges heat between the refrigerant that passes through the air conditioning side passage 21A and the case side passage 21B that are formed inside, thereby cooling the low pressure side of the air conditioning refrigerant circuit 7 and cooling it. The storage facility refrigerant circuit 9 is thermally connected to the high pressure side.

  The outlet of the case side passage 21 </ b> B of the cascade heat exchanger 21 is connected to the other inlet of the four-way valve 39, and the other outlet of the four-way valve 39 is connected to the other inlet of the four-way valve 41. The other outlet of the four-way valve 41 exits from the outdoor unit 12 and branches into the room 2 (inside the store). One of the branched pipes is connected to the inlet of the refrigeration evaporator 43 via an electromagnetic valve 46 and an expansion valve 44. The other is connected to the inlet of the refrigeration evaporator 49 through the electromagnetic valve 52 and the expansion valve 51.

  The outlet of the refrigeration evaporator 49 is connected to the suction side of the compressor 54 via the check valve 30 (the check valve 30 is in the forward direction on the compressor 54 side). This compressor 54 is a compressor having a smaller output than the compressor 37, and its discharge side is connected to one inlet of the four-way valve 42, and one outlet of the four-way valve 42 is connected to the outlet side of the refrigeration evaporator 43. After being connected, it is connected to the suction side of the compressor 37 via the oil separator 45. That is, the compressor 54 and the compressor 37 are connected in series on the refrigerant circuit.

  The other inlet of the four-way valve 42 is joined to a pipe line on the inlet side of the compressor 54, and the other outlet of the four-way valve 42 is an inlet of the case side passage 21 </ b> B of the cascade heat exchanger 21 through a check valve 61. It is joined to the side pipe line. The check valve 61 has a forward direction on the cascade heat exchanger 21 side. Hereinafter, the pipe line from the four-way valve 42 to the inlet side of the case side passage 21 </ b> B of the cascade heat exchanger 21 is referred to as a pipe line 70. A predetermined amount of refrigerant such as R-410A and R-404A is sealed in the refrigerant circuits 7 and 9, for example.

  Here, in the air-conditioning refrigeration apparatus 1 according to the present embodiment, the refrigerant (cooling refrigerant) discharged from the refrigeration evaporators 43 and 49 is used as one of the compressors 37 and 54 of the cooling apparatus 8. A bypass path that leads to the inlet of the cascade heat exchanger 21 via the other compressor without being routed can be formed. That is, by switching the four-way valve 42, as shown in FIG. 2, a first bypass path 70 that connects the refrigerant passage between the outlet of the evaporator 43 and the compressor 54 and the outlet side of the evaporator 49, A second bypass path 80 that connects the refrigerant path on the discharge side of the compressor 54 and the refrigerant path on the inlet side of the cascade heat exchanger 21 is formed.

  By forming the bypass paths 70 and 80 in this way, for example, when the compressor 37 fails, the refrigerant (cooling refrigerant) that has come out of the evaporators 43 and 49 is merged in the bypass path 70 and then compressed. It can be led to the inlet of the cascade heat exchanger 21 via the machine 54 and the like without passing through the compressor 37 in the bypass path 80 (see arrow α in FIG. 2). Further, for example, when the compressor 54 fails, the refrigerant (cooling refrigerant) from the evaporators 43 and 49 is merged in the bypass path 70, and then the compressor 37 and the like are connected without passing through the compressor 54. And can be led to the inlet of the cascade heat exchanger 21 (see arrow β in FIG. 2). In addition, a check valve 61 is provided in the bypass path 80, thereby preventing a reverse flow of the refrigerant supplied to the cascade heat exchanger 21 through the four-way valve 41 to the bypass path 80.

  Moreover, in this air-conditioning refrigeration apparatus 1, among the components of the cooling device 8, the compressor 54 for refrigeration amplification is covered with an exterior case together with its peripheral components, thereby providing a unit ( 90) (referred to as a refrigeration amplifier). Thereby, it is possible to arrange the components around the compressor 54 at an arbitrary position such as the outer wall of the convenience store or the ground.

  FIG. 3 is a perspective view showing the appearance of the outdoor unit 12, and FIG. 4 is a top view of the outdoor unit 12 with the top panel 12A removed. The outdoor unit 12 includes air conditioner side components (compressors 13A and 13B, an accumulator 23, an oil separator 10, and a heat source side heat exchanger other than the components installed in the indoor unit 11 in the air conditioner (air conditioning system unit) 6). 16, the blower 24, the outdoor unit controller 26, and the like, and the cooling device (cooling system unit) 8, components other than components arranged on the refrigeration case 3 and refrigeration case 4 side and cooling system side components other than the refrigeration amplifier 90 ( A compressor 37, an oil separator 31, a receiver tank 36, a condenser 38, a blower 35, a refrigerator controller 32, and the like).

  More specifically, in the outdoor unit 12, as shown in FIG. 4, the blower 24 is arranged on the left side when viewed from the front side, and air-conditioning system side components other than the blower 24 are arranged around the blower 24. In addition, the blower 35 is disposed on the right side when viewed from the front side, and cooling system side components other than the blower 35 are disposed around the blower 35. Here, in the space on the front side between the blower 24 and the blower 35, compressors 13A and 13B on the air conditioning system side are disposed on the substantially lower left side, and the compressor 37 on the cooling system side is disposed on the lower right side. At the same time, an outdoor unit controller 26 is disposed on the upper left side, and a refrigerator controller 32 is disposed on the upper right side. That is, in the outdoor unit 12, the air conditioning system side component and the cooling system side component are arranged separately on the left and right. Thus, by arranging the air conditioning system side components and the cooling system side components separately on the left and right sides, the air conditioning system side and the cooling system side can be easily assembled and maintained. It is possible to shorten the length of the pipe and the length of the pipe on the cooling system side.

  The operation of the air conditioning refrigeration apparatus 1 will be described under the above configuration. The compressors 37 and 13A are inverter-controlled, and the compressor 13B and the compressor 54 are operated at a constant speed. The overall operation of the air-conditioning / refrigeration apparatus 1 is controlled by a main controller (main control means) 56 composed of a general-purpose microcomputer. Here, the main controller 56 is provided with a remote operation device (remote control (commonly called remote control)) 57 for giving various instructions to the main controller 56. The remote operation device 57 is a liquid crystal for displaying various information. A display unit including a panel and various operation elements are provided, and various instructions from the user can be input through the operation of the operation elements.

  The main controller 56 is connected to the outdoor unit controller 26, the indoor unit controller 28, the refrigerator controller 32, the refrigeration case controller 50, and the refrigeration case controller 55 so that data communication is possible. Receive and collect. Then, based on the received data, an optimum operation pattern at that time, which will be described later, is determined, and the data relating to this optimum operation pattern and the operation data of each device are stored in the outdoor unit controller 26, the indoor unit controller 28, the refrigerator controller 32, and the refrigerator. The data is transmitted to the case controller 50 and the refrigeration case controller 55. The outdoor unit controller 26, the indoor unit controller 28, the refrigerator controller 32, the refrigeration case controller 50, and the refrigeration case controller 55 are described later based on the data regarding the optimum operation pattern received from the main controller 56 and the operation data of each device. Executes the control action to be performed.

(1) Optimal operation pattern 1: Air conditioner cooling operation (Fig. 1)
First, when the main controller 56 determines that the cooling operation of the air conditioner 6 is optimal in summer or the like, the data related to the optimal operation pattern 1 is the outdoor unit controller 26, the indoor unit controller 28, the refrigerator controller 32, the refrigeration case controller. 50 and the refrigeration case controller 55.

  Based on the transmission data from the main controller 56, the outdoor unit controller 26 causes the one inlet of the four-way valve 14 to communicate with one outlet and the other inlet to the other outlet. The expansion valve 17 is fully opened. Then, the compressors 13A and 13B are operated. The outdoor unit controller 26 controls the capacity by adjusting the operating frequency of the compressor 13A.

  When the compressors 13A and 13B are operated, the high-temperature and high-pressure gas refrigerant discharged from the discharge sides of the compressors 13A and 13B enters the inlet side 16A of the heat source side heat exchanger 16 via the four-way valve 14. Outside air is ventilated by the air blower 24 to the heat source side heat exchanger 16, and the refrigerant dissipates heat here to be condensed and liquefied. That is, in this case, the heat source side heat exchanger 16 functions as a condenser. The liquid refrigerant exits from the outlet side 16B from the inlet side 16A of the heat source side heat exchanger 16 via the outlet side 16B. And after passing the expansion valve 17, it branches. One of the branched branches reaches the expansion valve 18, where it is throttled to a low pressure (decompression), and then flows into the use side heat exchanger 27 where it evaporates.

  The air in the room 2 (inside the store) is ventilated by the blower 15 through the use side heat exchanger 27, and the air in the room 2 is cooled by an endothermic action due to evaporation of the refrigerant. Thereby, the room 2 (inside the store) is cooled. The low-temperature gas refrigerant that has exited from the use-side heat exchanger 27 passes through the four-way valve 14, the check valve 22, and the accumulator 23 in order and repeats circulation that is sucked into the suction sides of the compressors 13 </ b> A and 13 </ b> B.

  The indoor unit controller 28 uses the heat on the use side heat exchanger 27 so that the temperature of the room 2 (inside the store) is set to a preset temperature based on the temperature of the use side heat exchanger 27 and the air temperature sucked into the use side heat exchanger 27. The blower 15 that ventilates the ventilator 27 is controlled. Information from the indoor unit controller 28 is transmitted to the main controller 56, and the outdoor unit controller 26 controls the operation of the compressors 13A and 13B based on this information.

  The other refrigerant branched after passing through the check valve 5C reaches the expansion valve 19, where it is throttled to a low pressure (decompression), and then flows into the air conditioning side passage 21A of the cascade heat exchanger 21 where it evaporates. . The cascade heat exchanger 21 is cooled by the endothermic action due to the evaporation of the refrigerant in the air-conditioning refrigerant circuit 7 and becomes a low temperature. The low-temperature gas refrigerant exiting the cascade heat exchanger 21 repeats circulation through the accumulator 23 and sucked into the suction sides of the compressors 13A and 13B.

  The outdoor unit controller 26 has a room temperature, a refrigerant temperature at the entrance / exit of the use side heat exchanger 27, or a temperature of the room 2 (inside the store) so that the temperature is set by the user using the remote control device 29, or Based on the temperature of the use side heat exchanger 27, the operating frequency of the compressor 13A and the opening degree of the expansion valve 18 are adjusted. Further, the outdoor unit controller 26 controls the expansion valve 19 so that the difference between the inlet temperature TC1 and the outlet temperature TC2 of the case side passage 21B of the cascade heat exchanger 21 becomes a preset temperature difference (for example, 20 ° C.). Supercooling control is performed by adjusting the valve opening.

  Further, the indoor unit controller 28 uses the temperature on the use side heat exchanger 27 and the air temperature sucked into the use side heat exchanger 27 to set the temperature of the room 2 (inside the store) to a preset set temperature. The blower 15 that ventilates the heat exchanger 27 is controlled.

  On the other hand, the refrigerator controller 32 connects the one inlet of the four-way valve 39 of the refrigerant circuit 9 for the cooling storage facility of the cooling device 8 to one outlet, and connects the other inlet to the other outlet. Further, the one inlet of the four-way valve 41 is communicated with one outlet, and the other inlet is communicated with the other outlet. Then, the compressor 37 and the compressor 54 are operated. The high-temperature and high-pressure gas refrigerant discharged from the compressor 37 is separated by the oil separator 31 and then enters the inlet side 38 </ b> A of the condenser 38 through the four-way valve 39. Outside air is also passed through the condenser 38 by the blower 35, and the refrigerant flowing into the condenser 38 dissipates heat and condenses there. The solenoid valve 47 is fully opened.

  The refrigerant that has passed through the inlet side 38A of the condenser 38 reaches the outlet side 38B and exits there. The refrigerant from the condenser 38 enters the receiver tank 36 from the inlet side of the receiver tank 36, and is temporarily stored therein to separate the gas / liquid. The separated liquid refrigerant exits from the outlet of the receiver tank 36, passes through the four-way valve 41, and then enters the case side passage 21 </ b> B of the cascade heat exchanger 21. The refrigerant in the refrigerant circuit 9 for the cooling storage facility that has entered the case-side passage 21B is cooled by the cascade heat exchanger 21 that is at a low temperature due to evaporation of the refrigerant in the air-conditioning refrigerant circuit 7 as described above, and is further in a supercooled state. Increase. More specifically, as described above, the outdoor unit controller 26 is cooled by a preset temperature difference (for example, 20 ° C.). Since the receiver tank 36 is disposed immediately after the condenser 38 as described above, heat loss during supercooling can be eliminated and the amount of refrigerant can be adjusted.

  The refrigerant supercooled in the cascade heat exchanger 21 is branched after sequentially passing through the four-way valve 39 and the four-way valve 41, and one of the refrigerant passes through the electromagnetic valve 46 to the expansion valve 44, where it is throttled ( Pressure reduction), it flows into the refrigeration evaporator 43 and evaporates there. In the refrigerator 43 for refrigeration, the air in the refrigerator case 3 is ventilated and circulated by the blower 20, and the air in the refrigerator is cooled by an endothermic action due to evaporation of the refrigerant. Thereby, the inside cooling of the refrigeration case 3 is performed. The low-temperature gas refrigerant exiting the refrigeration evaporator 43 joins and then reaches the outlet side of the oil separator 45 of the compressor 54.

  The other refrigerant branched out of the cascade heat exchanger 21 passes through the electromagnetic valve 52 and reaches the expansion valve 51. After being throttled (decompression), it flows into the refrigeration evaporator 49 where it evaporates. The internal air of the freezing case 4 is also ventilated and circulated by the blower 25 also to the freezing evaporator 49, and the internal air is cooled by the endothermic action due to the evaporation of the refrigerant, and the internal cooling of the freezing case 4 is performed. .

  The low-temperature gas refrigerant exiting the freezing evaporator 49 reaches the compressor 54 via the check valve 30, where it is compressed and pressurized to the pressure on the outlet side of the refrigerating evaporator 43, and then from the compressor 54. After being discharged and separated by the oil separator 45, the oil is combined with the refrigerant from the refrigeration evaporator 43. The merged refrigerant repeats circulation that is sucked into the suction side of the compressor 37.

  The refrigeration case controller 50 is configured such that the internal temperature of the refrigeration case 3, the temperature of the discharged chilled air that has passed through the refrigeration evaporator 43, the temperature of the intake chilled air to the refrigeration evaporator 43, The valve opening degree of each expansion valve 44 is controlled based on the temperature of the refrigeration evaporator 43. Thereby, it is set as the appropriate superheat degree (constant superheat degree), maintaining the inside of the refrigerator | coolant case 3 cooling at the refrigeration temperature mentioned above.

  Further, the refrigeration case controller 55 is configured such that the internal temperature of the refrigeration case 4, the cold air temperature discharged through the refrigeration evaporator 49, the cold air temperature sucked into the refrigeration evaporator 49, and the refrigerant temperature on the outlet side of the refrigeration evaporator 49. Alternatively, the valve opening degree of the expansion valve 51 is controlled based on the temperature of the refrigeration evaporator 49. As a result, while maintaining the inside of the freezing case 4 to be cooled to the above-described freezing temperature, an appropriate degree of superheat (constant superheat) is obtained.

  The operating frequency of the compressor 37 is controlled based on the pressure on the suction side (low pressure of the refrigerant circuit 9 for the cooling storage facility). When all the expansion valves 44 and 51 are fully closed, the expansion valves 44 and 51 are stopped, and when one of them is opened, the operation is performed.

  Thus, since the high pressure side refrigerant of the refrigerant circuit 9 for the cooling storage facility can be supercooled by the low pressure side refrigerant of the air conditioning refrigerant circuit 7 flowing through the air conditioning side passage 21A of the cascade heat exchanger 21, the refrigeration case 3 or The cooling capacity in the evaporators 43 and 49 of the refrigeration case 4 and the operation efficiency of the refrigerant circuit 9 for the cooling storage facility are improved. In this case, since the refrigerant on the high pressure side of the refrigerant circuit 9 for the cooling storage facility flows into the case side passage 21B of the cascade heat exchanger 21 via the condenser 38, the degree of superheat of the air conditioning refrigerant circuit 7 is also in an appropriate range. Can be maintained.

  In addition, the pressure of the refrigerant discharged from the refrigeration evaporator 49 of the refrigerant circuit 9 for the cooling storage facility is lower than that of the refrigerant discharged from the refrigeration evaporator 43 because the evaporation temperature becomes lower, but the refrigeration evaporator 43 Before being merged with the refrigerant discharged from the refrigerant, the compressor 54 compresses the pressure and raises the pressure, so that the inside of the refrigerator case 3 and the refrigerator case 4 is cooled smoothly by the evaporators 43 and 49, respectively, for the cooling storage facility. It becomes possible to operate without any trouble by adjusting the pressure of the refrigerant sucked into the compressor 37 of the refrigerant circuit 9.

(2) Optimal operation pattern 2: heating operation of air conditioner Next, the heating operation of the air conditioner 6 in winter or the like will be described with reference to FIG. When the main controller 56 determines that the heating operation of the air conditioner 6 is optimal, the data regarding the optimal operation pattern 2 includes the outdoor unit controller 26, the indoor unit controller 28, the refrigerator controller 32, the refrigeration case controller 50, and the refrigeration case controller 50. It is transmitted to the case controller 55.

  Based on the transmission data from the main controller 56, the outdoor unit controller 26 switches so that one inlet of the four-way valve 14 communicates with the other outlet and the other inlet communicates with one outlet. The expansion valve 17 is fully closed and the expansion valve 18 is fully opened. Then, the compressors 13A and 13B are operated. When the compressors 13A and 13B are operated, the high-temperature and high-pressure gas refrigerant discharged from the discharge sides of the compressors 13A and 13B enters the use-side heat exchanger 27 through the oil separator 10 and the four-way valve 14. As described above, the air in the room 2 (inside the store) is passed through the use side heat exchanger 27 by the blower 15, and the refrigerant dissipates heat to heat the air in the room 2, while the liquid itself condenses. Thereby, the room 2 (inside the store) is heated.

  The refrigerant liquefied in the use side heat exchanger 27 exits from the use side heat exchanger 27, passes through the expansion valve 18, reaches the expansion valve 19, and is throttled to a low pressure (decompression), and then the cascade heat exchanger 21. The air flows into the air conditioning side passage 21A, evaporates and absorbs heat there, and then repeats circulation that is sucked into the suction sides of the compressors 13A and 13B through the accumulator 23.

  The outdoor unit controller 26 controls the operating frequency of the compressor 13A so that the temperature of the room 2 (inside the store) becomes a set temperature set by the user using the remote control device 29, and the cooling operation described above. Similarly, the supercooling control is performed by adjusting the valve opening degree of the expansion valve 19. Further, the indoor unit controller 28 uses the temperature on the use side heat exchanger 27 and the air temperature sucked into the use side heat exchanger 27 to set the temperature of the room 2 (inside the store) to a preset set temperature. The blower 15 that ventilates the heat exchanger 27 is controlled.

  On the other hand, the refrigerator controller 32 switches the one-way inlet 39 of the four-way valve 39 of the refrigerant circuit 9 for the cooling storage facility of the cooling device 8 to communicate with the other outlet, and the other inlet communicates with one outlet. The one inlet 41 is switched to communicate with the other outlet, and the other inlet is communicated with one outlet. The other solenoid valves and the like are the same as those in the cooling operation of the air conditioner 6 described above. That is, the electromagnetic valves 46 and 52 are opened, and the compressors 37 and 54 are operated.

  Thus, the high-temperature and high-pressure gas refrigerant discharged from the compressor 37 sequentially passes through the four-way valves 39 and 41 and first enters the case-side passage 21B of the cascade heat exchanger 21. That is, the high-temperature and high-pressure gas refrigerant discharged from the compressor 37 is directly supplied to the case side passage 21 </ b> B of the cascade heat exchanger 21 before going to the condenser 38. Since the refrigerant in the refrigerant circuit 9 for the cooling storage facility 9 that has entered the case side passage 21B dissipates heat in the cascade heat exchanger 21, it is cooled by the refrigerant in the air conditioning refrigerant circuit 7 that evaporates in the air conditioning side passage 21A as described above. The refrigerant in the refrigerant circuit 9 for cooling is cooled, and the refrigerant in the refrigerant circuit 7 for air conditioning pumps up the waste heat of the refrigerant in the refrigerant circuit 9 for cooling storage equipment.

  The refrigerant that has passed through the case side passage 21B of the cascade heat exchanger 21 then enters the inlet side 38A of the condenser 38 via the four-way valve 39. Outside air is also passed through the condenser 38 by the blower 35, and the refrigerant flowing into the condenser 38 dissipates heat and condenses there.

  The refrigerant that has passed through the inlet side 38A of the condenser 38 reaches the outlet side 38B and exits there. The refrigerant from the condenser 38 enters the receiver tank 36 from the inlet side of the receiver tank 36, and is temporarily stored therein to separate the gas / liquid. The separated liquid refrigerant exits from the outlet of the receiver tank 36, passes through the four-way valve 41, and then branches, and goes to the electromagnetic valves 46 and 52 as described above.

  By such operation, during the heating operation of the air conditioning refrigerant circuit 7 of the air conditioner 6, the waste heat of the high-pressure side refrigerant of the refrigerant circuit 9 for the cooling storage facility is recovered by the cascade heat exchanger 21 and the air conditioning refrigerant circuit 7. It becomes possible to convey to the use side heat exchanger 27. As a result, the heating capacity of the air conditioner 6 can be improved. In general, the efficiency of the air-conditioning / refrigeration apparatus 1 that cools the indoor air-conditioning and the refrigeration case 3 and the freezing case 4 is improved, and energy is saved. Can be achieved.

  Particularly in this case, since the refrigerant on the high pressure side of the refrigerant circuit 9 for the cooling storage facility is passed through the cascade heat exchanger 21 before the condenser 38, the waste heat recovery from the high pressure side refrigerant of the refrigerant circuit 9 for the cooling storage facility is performed. The heating capacity in the use side heat exchangers 27 and 27 of the air conditioning refrigerant circuit 7 can be further improved.

  Here, when the air conditioner 6 is lightly loaded, such as when the store 2 is relatively warm, the outdoor unit controller 26 reduces the refrigerant flow rate by reducing the valve opening of the expansion valve 19, so that cascade heat exchange is performed. However, in the present invention, the refrigerant on the high pressure side of the refrigerant circuit 9 for the cooling storage facility is passed through the cascade heat exchanger 21 and then condensed. Therefore, when the heat radiation amount of the refrigerant in the cascade heat exchanger 21 of the cooling storage facility refrigerant circuit 9 becomes excessive during the heating operation of the air conditioning refrigerant circuit 7, the condenser 38. The excess amount of heat is released at. Thereby, a stable waste heat recovery operation can be realized.

  Furthermore, during the heating operation of the air conditioner 6 as described above, if the amount of heat that the air conditioner 6 recovers from the high-pressure side refrigerant of the refrigerant circuit 9 for the cooling storage facility in the cascade heat exchanger 21, the outdoor unit controller 26 is Waste heat recovery is performed by controlling the valve opening of the expansion valve 19, and in addition to the waste heat recovery, the valve opening of the expansion valve 17 is controlled so as to maintain the necessary heat amount (heat recovery control). Also in this case, the cooling device 8 efficiently recovers heat by flowing the refrigerant through the cascade heat exchanger 21. In addition, when the air conditioner 6 performs heating operation as described above, if the air conditioner 6 recovers excessively from the high-pressure side refrigerant of the refrigerant circuit 9 for the cooling storage facility by the cascade heat exchanger 21, the outdoor unit controller 26 The expansion valve 19 is fully closed and the expansion valve 18 is fully opened, and the valve opening degree of the expansion valve 17 is controlled so as to recover the necessary heat amount (heat recovery control). Further, the cooling device 8 causes the refrigerant to flow through the cascade heat exchanger 21 and increases the supercooling when the recovered heat amount becomes excessive. Thereby, a more stable waste heat recovery operation can be realized.

  Further, as described above, the flow paths are switched using the four-way valves 39 and 41, and the cooling air circuit 7 is connected to the condenser 38 and the outlet of the refrigerant circuit 9 for the cooling storage facility during the cooling operation and the heating operation. The flow direction of the refrigerant flowing through the receiver tank 36 is the same. As a result, the pressure loss of the refrigerant flowing in the refrigerant circuit 9 for the cooling storage facility is reduced compared to the case where the refrigerant flows in the condenser 38 and the receiver tank 36 are opposite between the cooling operation and the heating operation. It becomes possible to prevent or suppress, and efficient operation becomes possible. In particular, since the flow path is switched by the two four-way valves 39, 41, the configuration of the refrigerant circuit 9 for the cooling storage facility can be simplified.

(3) Optimal operation pattern at the time of failure detection Next, control (backup operation) when the refrigeration system (compressor 37) or the refrigeration system (compressor 54) fails will be described.

  First, a sequence when the compressor 37 or the compressor 54 fails will be described with reference to FIG. When the compressor 37 or the compressor 54 fails, the refrigerator controller 32 detects the failure (step S1) and notifies the main controller 56 to that effect (step S2). When the main controller 56 is notified of the failure of the compressor 37 or the compressor 54, the main controller 56 determines an optimal operation pattern (optimal operation patterns 3, 4, 5, 6 to be described later) according to the failure location, and this optimal operation. Data about the pattern is transmitted to the outdoor unit controller 26, the indoor unit controller 28, the refrigerator controller 32, the refrigeration case controller 50, and the refrigeration case controller 55 (step S3).

  Based on the transmission data from the main controller 56, the outdoor unit controller 26, the indoor unit controller 28, the refrigerator controller 32, the refrigeration case controller 50, and the refrigeration case controller 55 start a backup operation described later (steps S5 and S6). , S7). The malfunctioning compressor 37 or compressor 54 is stopped.

  Further, the main controller 56 notifies the failure location to the terminal device of the service company (temperature monitoring center) via a predetermined communication line (step S4). As a result, a service person is dispatched from the service company promptly (within about 90 minutes) to take countermeasures such as repairs.

(3.1) Optimal operation pattern 3 (operation pattern at the time of failure detection): control when the refrigeration system (compressor 37) fails during cooling operation of the air conditioner (FIG. 2)
Control when the compressor 37 for refrigeration breaks down during the cooling operation as described above will be described with reference to FIG. In this case, a part of the refrigerant (cooling refrigerant) in the cooling device 8 is indicated by an arrow α. Hereinafter, a different part from the above-mentioned cooling operation will be described.

  Based on the transmission data from the main controller 56, the outdoor unit controller 26 first sets the outlet temperature TC2 of the case side passage 21B of the cascade heat exchanger 21 to a predetermined failure outlet temperature (for example, −10 ° C.). The amount of refrigerant (air-conditioning refrigerant) supplied is controlled by adjusting the valve opening of the expansion valve 19. Here, the outlet temperature at the time of failure is a temperature that gives priority to refrigeration / refrigeration in the refrigeration case 4 or the refrigeration case 3, and is a temperature that is determined according to the refrigerant cooling capacity of the cooling device 8 by the air conditioner 6. That is, the condensation temperature on the cooling device (cooling system section) 8 side is controlled to the failure outlet temperature giving priority to the refrigeration / refrigeration in the refrigeration case 4 or the refrigeration case 3 on the air conditioner 6 side.

  Moreover, the outdoor unit controller 26 and the indoor unit controller 28 set the set temperature of the room 2 to a preset failure time set temperature (for example, 20 ° C.), and set the compressor so that the set temperature at the time of failure is set. The operation of 13A and 13B and the blower 15 are controlled. Thereby, the temperature of the room 2 can be lowered and the load (refrigeration load, refrigeration load) on the cooling device 8 side can be reduced. Note that the outdoor unit controller 26 and the indoor unit controller 28 change the freeze protection control condition based on the evaporation temperature of the indoor unit 11 from a normal Hz drop temperature condition (for example, 2 ° C. or lower) to a lower temperature (for example, −12 ° C.). It is also made to change the freeze protection control.

  On the other hand, the refrigerator controller 32 switches the four-way valve 42 based on the transmission data from the main controller 56 to connect the outlet side of the evaporator 43 and the outlet side of the evaporator 49 as shown in FIG. The discharge side of the machine 54 and the inlet side of the cascade heat exchanger 21 are connected (the four-way valve 42 and the refrigerator controller 32 function as bypass path forming means). Further, the malfunctioning compressor 37 is stopped, and the solenoid valve 47 is fully closed. In this case, the refrigerant discharged from the evaporator 43 is merged with the refrigerant of the evaporator 49 via the bypass path 70, passes through the compressor 54, and then passes through the bypass path 80 to the case side of the cascade heat exchanger 21. Enter passage 21B. That is, the refrigerant discharged from the evaporators 43 and 49 enters the cascade heat exchanger 21 without passing through the compressor 37, and the cascade heat exchanger is at a low temperature due to the evaporation of the refrigerant in the air conditioning refrigerant circuit 7 as described above. 21 is cooled. More specifically, the refrigerant in the refrigerant circuit 9 for the cooling storage facility is cooled by the outdoor unit controller 26 at the outlet of the cascade heat exchanger 21 until the set temperature at the time of failure (−10 ° C.) as described above.

  The refrigerant supercooled by the cascade heat exchanger 21 is branched after sequentially passing through the four-way valve 39 and the four-way valve 41, and one of the refrigerant passes through the electromagnetic valve 46 and reaches the expansion valve 44, and is throttled there. (Decompression) flows into the refrigeration evaporator 43 and evaporates there. Thereby, the inside cooling of the refrigeration case 3 is performed. The other refrigerant branched out of the cascade heat exchanger 21 passes through the electromagnetic valve 52 and reaches the expansion valve 51. After being throttled (decompression), it flows into the refrigeration evaporator 49 and evaporates there. . Thereby, the inside cooling of the freezing case 4 is performed.

  As described above, when the compressor 37 fails, the refrigerant discharged from the evaporators 43 and 49 is allowed to flow into the cascade heat exchanger 21 without passing through the compressor 37. The refrigerant can be circulated in the circuit 9 and the refrigerant in the refrigerant circuit 9 for the cooling storage facility is cooled to a predetermined temperature (failure) by the low-pressure side refrigerant in the air-conditioning refrigerant circuit 7 flowing in the air-conditioning side passage 21A of the cascade heat exchanger 21. Therefore, the cooling of the refrigerator case 3 and the freezing case 4 can be continued. Furthermore, since the set temperature of the room 2 of the air conditioner 6 is changed to a preset temperature at the time of failure, the temperature of the room 2 can be lowered to reduce the refrigeration / refrigeration load of the cooling device 8. As a result, the products in the refrigerated case 3 and the frozen case 4 can be greatly delayed from being damaged, and it is almost certainly possible to avoid damaging the products before the service person comes and repairs them. It becomes possible.

  In the above case, cooling in the refrigerator case 4 may be prioritized. Specifically, the expansion valve 44 may be fully closed to cut off the supply of the refrigerant to the refrigeration evaporator 43 and supply all the refrigerant (cooling refrigerant) to the refrigeration evaporator 49.

(3.2) Optimal operation pattern 4 (operation pattern when failure is detected): Control when the refrigeration system (compressor 54) fails during cooling operation of the air conditioner (FIG. 2)
Control when the compressor 54 for refrigeration breaks down during the cooling operation as described above will be described with reference to FIG. In this case, a part of the refrigerant (cooling refrigerant) in the cooling device 8 is indicated by an arrow β. Hereinafter, a different part from the above-mentioned cooling operation will be described.

  The outdoor unit controller 26, based on the transmission data from the main controller 56, sets the outlet temperature TC2 of the case side passage 21B of the cascade heat exchanger 21 to a predetermined outlet temperature as in the case of the optimum operation pattern 3 described above. The outdoor unit controller 26 and the indoor unit controller 28 adjust the set temperature of the indoor 2 to the set temperature at the time of failure (for example, 20 ° C.). And the operation of the compressors 13A and 13B and the blower 15 are controlled so as to obtain the set temperature at the time of failure.

  On the other hand, the refrigerator controller 32 switches the four-way valve 42 based on the transmission data from the main controller 56 as in the case of the optimum operation pattern 3 described above, and sets the outlet side of the evaporator 43 as shown in FIG. The outlet side of the evaporator 49 is connected, and the discharge side of the compressor 54 and the inlet side of the cascade heat exchanger 21 are connected. Further, the malfunctioning compressor 54 is stopped. In this case, the refrigerant discharged from the evaporator 49 is merged with the refrigerant of the evaporator 43 via the bypass path 70, passes through the compressor 37, and then enters the case side passage 21 </ b> B of the cascade heat exchanger 21. That is, the refrigerant discharged from the evaporators 43 and 49 is supplied to the compressor 37 without passing through the compressor 54, and the cascade heat exchanger 21 is at a low temperature due to the evaporation of the refrigerant in the air conditioning refrigerant circuit 7 as described above. Cooled by. As a result, the refrigerant supercooled in the cascade heat exchanger 21 is branched after sequentially passing through the four-way valve 39 and the four-way valve 41, and one of the refrigerant enters the refrigeration evaporator 43 via the electromagnetic valve 46 and the expansion valve 44. It flows into the refrigerator case 3 and is used to cool the refrigerator case 3, and the other flows into the freezing evaporator 49 through the solenoid valve 52 and the expansion valve 51 and is used to cool the refrigerator case 4.

  As described above, when the compressor 54 fails, the refrigerant discharged from the evaporators 43 and 49 flows into the cascade heat exchanger 21 without passing through the compressor 54. Since the refrigerant can be circulated through the circuit 9 and the refrigerant in the refrigerant circuit 9 for the cooling storage facility is supercooled to a predetermined temperature (set temperature at the time of failure) by the cascade heat exchanger 21, the refrigeration case 3 and the freezing case The inside cooling of 4 can be continued. Furthermore, since the preset temperature of the indoor 2 of the air conditioner 6 is changed to a preset failure temperature (20 ° C.), the temperature of the indoor 2 can be lowered to reduce the refrigeration / freezing load of the cooling device 8. it can. As a result, the product in the refrigerated case 3 and the freezer case 4 can be greatly delayed from being damaged as in the case of the compressor 37 being broken, and the product is damaged before the serviceman comes to repair it. It becomes possible to avoid almost certainly.

(3.3) Optimal operation pattern 5 (operation pattern at the time of failure detection): control when the refrigeration system (compressor 37) fails during the heating operation of the air conditioner (FIG. 7)
Control when the compressor 37 for refrigeration breaks down during the heating operation as described above will be described with reference to FIG. In this case, a part of the refrigerant (cooling refrigerant) in the cooling device 8 is indicated by an arrow γ. Hereinafter, a different part from the above-mentioned heating operation will be described.

  The outdoor unit controller 26 determines the outlet temperature TC2 of the case side passage 21B of the cascade heat exchanger 21 based on the transmission data from the main controller 56 in the same manner as in the case of the optimum operation patterns 3 and 4 described above. While adjusting the valve opening degree of the expansion valve 19 so as to be the outlet temperature (for example, −10 ° C.), the outdoor unit controller 26 and the indoor unit controller 28 set the set temperature of the room 2 to the set temperature at the time of failure (for example, 16 The operation of the compressors 13A and 13B and the blower 15 are controlled so that the set temperature at the time of failure is set.

  On the other hand, the refrigerator controller 32 switches the four-way valve 42 based on the transmission data from the main controller 56 as in the case of the optimum operation patterns 3 and 4 described above, and the outlet of the evaporator 43 as shown in FIG. The outlet side of the evaporator 49 and the discharge side of the compressor 54 and the inlet side of the cascade heat exchanger 21. Further, the malfunctioning compressor 37 is stopped, and the solenoid valve 47 is fully closed. In this case, similarly to the case of the optimum operation pattern 3 described above, the refrigerant discharged from the evaporator 43 is merged with the refrigerant of the evaporator 49 via the bypass path 70, passes through the compressor 54, and then bypasses the bypass path 80. And enters the case side passage 21B of the cascade heat exchanger 21. That is, the refrigerant discharged from the evaporators 43 and 49 enters the cascade heat exchanger 21 without passing through the compressor 37, and the cascade heat exchanger is at a low temperature due to the evaporation of the refrigerant in the air conditioning refrigerant circuit 7 as described above. 21 is cooled. More specifically, the refrigerant in the refrigerant circuit 9 for the cooling storage facility is cooled by the outdoor unit controller 26 at the outlet of the cascade heat exchanger 21 until the set temperature at the time of failure (−10 ° C.) as described above. As a result, the refrigerant supercooled in the cascade heat exchanger 21 is branched after sequentially passing through the four-way valve 39 and the four-way valve 41, and one of the refrigerant enters the refrigeration evaporator 43 via the electromagnetic valve 46 and the expansion valve 44. It flows into the refrigerator case 3 and is used to cool the refrigerator case 3, and the other flows into the freezing evaporator 49 through the solenoid valve 52 and the expansion valve 51 and is used to cool the refrigerator case 4.

  As described above, even when the compressor 37 fails during the heating operation, the cascade heat exchanger does not pass the refrigerant from the evaporators 43 and 49 without passing through the compressor 37 as in the case of the optimum operation pattern 3 described above. 21, the refrigerant can be circulated through the refrigerant circuit 9 for the cooling storage facility by the compressor 54, and the refrigerant in the refrigerant circuit 9 for the cooling storage facility can be circulated by the cascade heat exchanger 21 at a predetermined temperature (when a failure occurs). Therefore, the cooling of the refrigerator case 3 and the freezing case 4 can be continued. Furthermore, since the preset temperature of the indoor 2 of the air conditioner 6 is changed to a preset failure temperature (16 ° C.), the temperature of the indoor 2 can be lowered to reduce the refrigeration / freezing load of the cooling device 8. it can. As a result, the products in the refrigerated case 3 and the frozen case 4 can be greatly delayed from being damaged, and it is almost certainly possible to avoid damaging the products before the service person comes and repairs them. It becomes possible.

(3.4) Optimal operation pattern 6 (operation pattern when failure is detected): Control when the refrigeration system (compressor 54) fails during heating operation of the air conditioner (FIG. 7)
Control when the compressor 37 for refrigeration breaks down during the heating operation as described above will be described with reference to FIG. In this case, a part of the refrigerant (cooling refrigerant) in the cooling device 8 is indicated by an arrow δ. Hereinafter, a different part from the above-mentioned heating operation will be described.

  The outdoor unit controller 26 determines the outlet temperature TC2 of the case side passage 21B of the cascade heat exchanger 21 based on the transmission data from the main controller 56 in the same manner as in the case of the optimum operation patterns 3 and 4 described above. While adjusting the valve opening degree of the expansion valve 19 so as to be the outlet temperature (for example, −10 ° C.), the outdoor unit controller 26 and the indoor unit controller 28 set the set temperature of the room 2 to the set temperature at the time of failure (for example, 16 The operation of the compressors 13A and 13B and the blower 15 are controlled so that the set temperature at the time of failure is set.

  On the other hand, the refrigerator controller 32 switches the four-way valve 42 based on the transmission data from the main controller 56 and switches the four-way valve 42 based on the transmission data from the main controller 56 as in the case of the optimum operation patterns 3 and 4 described above. As shown in FIG. 7, the outlet side of the evaporator 43 and the outlet side of the evaporator 49 are connected, and the discharge side of the compressor 54 and the inlet side of the cascade heat exchanger 21 are connected. Further, the malfunctioning compressor 37 is stopped, and the solenoid valve 47 is fully closed. In this case, as in the case of the optimum operation pattern 4 described above, the refrigerant discharged from the evaporator 49 is merged with the refrigerant of the evaporator 43 via the bypass path 70, and after passing through the compressor 37, cascade heat exchange is performed. Enter the case side passage 21B of the vessel 21. That is, the refrigerant discharged from the evaporators 43 and 49 is supplied to the compressor 37 without passing through the compressor 54, and the cascade heat exchanger 21 is at a low temperature due to the evaporation of the refrigerant in the air conditioning refrigerant circuit 7 as described above. Cooled by. More specifically, as described above, the outdoor unit controller 26 cools at the outlet of the cascade heat exchanger 21 until the set temperature at the time of failure (−10 ° C.) is reached. As a result, the refrigerant supercooled in the cascade heat exchanger 21 is branched after sequentially passing through the four-way valve 39 and the four-way valve 41, and one of the refrigerant enters the refrigeration evaporator 43 via the electromagnetic valve 46 and the expansion valve 44. It flows into the refrigerator case 3 and is used to cool the refrigerator case 3, and the other flows into the freezing evaporator 49 through the solenoid valve 52 and the expansion valve 51 and is used to cool the refrigerator case 4.

  As described above, when the compressor 54 fails during the heating operation, the cascade heat exchanger does not pass the refrigerant from the evaporators 43 and 49 through the compressor 54 as in the case of the optimum operation pattern 4 described above. 21, the refrigerant can be circulated through the refrigerant circuit 9 for the cooling storage facility by the compressor 37, and the refrigerant in the refrigerant circuit 9 for the cooling storage facility can be circulated by the cascade heat exchanger 21 at a predetermined temperature (at the time of failure). Therefore, the cooling of the refrigerator case 3 and the freezing case 4 can be continued. Furthermore, since the preset temperature of the indoor 2 of the air conditioner 6 is changed to a preset failure temperature (16 ° C.), the temperature of the indoor 2 can be lowered to reduce the refrigeration / freezing load of the cooling device 8. it can. As a result, the products in the refrigerated case 3 and the frozen case 4 can be greatly delayed from being damaged, and it is almost certainly possible to avoid damaging the products before the service person comes and repairs them. It becomes possible.

  As described above, the air-conditioning refrigeration apparatus 1 according to the present embodiment compresses the refrigerant discharged from the evaporators 43 and 49 when the refrigeration system (compressor 37) or the refrigeration system (compressor 54) fails. By forming a bypass path that leads to the inlet of the cascade heat exchanger via the other compressor 54 (or 37) without passing through the machine 37 (or 54), a cooling storage facility is provided in the cascade heat exchanger 21. It is possible to continue cooling the refrigerant in the refrigerant circuit 9 and supplying it to the evaporators 43 and 49. Thereby, even if the compressors 37 and 54 of the cooling device 8 break down, the flow of the refrigerant does not stop, and the inside cooling of the refrigeration case 3 and the refrigeration case 4 can be continued. It is possible to greatly delay the damage of the product in the freezing case 4.

  Furthermore, in this embodiment, when the refrigeration system (compressor 37) or the refrigeration system (compressor 54) fails, the outlet temperature TC2 of the case side passage 21B of the cascade heat exchanger 21 is set to the outlet temperature at the time of failure (for example, −10 ° C.) by changing the control so that the refrigerant in the refrigerant circuit 9 for the cooling storage facility can be controlled to a temperature at which damage to the product in the refrigeration case 3 or the refrigeration case 4 can be reliably delayed. Further, it becomes possible to delay the damage of the products in the refrigerated case 3 and the frozen case 4 for a sufficient time (a sufficient time until the serviceman comes).

  Further, in this embodiment, when the refrigeration system (compressor 37) or the refrigeration system (compressor 54) fails, the set temperature in the room 2 of the air conditioner 6 is set to the set temperature at the time of failure with priority to refrigeration and refrigeration. Since the change is made, it is possible to delay damage to the products in the refrigerated case 3 and the frozen case 4.

  In the above-described embodiment, the present invention has been described by taking a convenience store as an example. However, the present invention is not limited thereto, and the present invention is effective for various air-conditioning refrigeration apparatuses that cool indoor air-conditioning and cooling storage facilities. Furthermore, each setting value and piping configuration shown in the embodiments are not limited thereto, and can be appropriately changed without departing from the gist of the present invention. Moreover, in the said Example, when the compressors 37 and 54 fail, the refrigerant | coolant which came out of the evaporators 43 and 49 is guide | induced to the inlet_port | entrance of a cascade heat exchanger, without passing through the failed compressor 37 (or 54). The case where the bypass path is formed and the control is changed so that the outlet temperature TC2 of the case side passage 21B of the cascade heat exchanger 21 becomes the outlet temperature at the time of failure (for example, −10 ° C.) has been described. It is sufficient to form at least a bypass path at the time of failure so that the refrigerant (cooling refrigerant) can be cooled, and the control of the cascade heat exchanger 21 may not be changed.

It is a figure explaining the system configuration containing the refrigerant circuit of an air-conditioning refrigerating device (at the time of air conditioning operation of an air conditioner). It is a figure explaining the driving | operation when the compressor of a cooling device fails at the time of the air conditioning machine of an air-conditioning refrigerating device cooling operation. It is a perspective view which shows the external appearance of the outdoor unit of an air-conditioning freezer. It is a top view in the state where an upper surface panel of an outdoor unit was removed. It is a figure explaining the heating operation of the air conditioner of an air-conditioning refrigerating apparatus. It is a figure explaining the sequence when the compressor of a cooling device fails. It is a figure explaining the operation | movement when the compressor of a cooling device malfunctions at the time of the heating operation of the air conditioner of an air-conditioning refrigerating apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Air-conditioning refrigeration equipment 3 Refrigeration case 4 Refrigeration case 6 Air conditioner 7 Air-conditioning refrigerant circuit 8 Cooling device 9 Refrigerating circuit for cooling storage equipment 13A, 13B, 37, 54 Compressor 14, 36, 41, 42 Four-way valve 16 Heat source side Heat exchanger 21 Cascade heat exchanger 28 User side heat exchanger 29, 57 Remote control device 38 Condenser 43 Refrigerator evaporator 49 Refrigerator evaporator

Claims (3)

An air conditioning system unit that includes a compressor, a heat source side heat exchanger, and a usage side heat exchanger and performs indoor air conditioning by the usage side heat exchanger, and two cooling compressors, a condenser, and a refrigerator that are connected in series A refrigeration system section that includes a refrigeration evaporator and a refrigeration evaporator and cools cooling storage equipment by the evaporator; a low-pressure air-conditioning refrigerant of the air-conditioning system section; and a high-pressure cooling of the refrigeration system section In an air-conditioning refrigeration apparatus that is thermally coupled with a cascade heat exchanger that is supplied with a refrigerant for use,
When one of the two cooling compressors fails, the cooling refrigerant from the evaporator passes through the other cooling compressor without passing through the failed cooling compressor. And an air-conditioning refrigeration apparatus comprising a bypass path forming means for forming a bypass path leading to the inlet of the cascade heat exchanger. The two cooling compressors are a refrigeration compressor and a freezing amplification compressor,
The bypass path forming means includes
When one of the two cooling compressors fails, the refrigerant passage between the outlet of the refrigeration evaporator and the compressor for refrigeration amplification, and the refrigerant on the outlet side of the refrigeration evaporator A first bypass path connecting the passage;
The air-conditioning refrigeration according to claim 2, wherein a refrigerant passage on the discharge side of the compressor for refrigeration amplification and a refrigerant passage on the inlet side of the cascade heat exchanger are connected to each other. apparatus. An air conditioning system unit that includes a compressor, a heat source side heat exchanger, and a usage side heat exchanger and performs indoor air conditioning by the usage side heat exchanger, and two cooling compressors, a condenser, and a refrigerator that are connected in series A refrigeration system section that includes a refrigeration evaporator and a refrigeration evaporator and cools cooling storage equipment by the evaporator; a low-pressure air-conditioning refrigerant of the air-conditioning system section; and a high-pressure cooling of the refrigeration system section In a control method of an air-conditioning refrigeration apparatus that is thermally connected with a cascade heat exchanger that is supplied with a refrigerant for use,
When one of the two cooling compressors fails, the refrigerant passage between the outlet of the refrigeration evaporator and the compressor for refrigeration amplification, and the refrigerant on the outlet side of the refrigeration evaporator A first bypass path connecting the passage;
The refrigerant on the discharge side of the compressor for refrigeration amplification and the second bypass path that connects the refrigerant passage on the inlet side of the cascade heat exchanger are formed, and the cooling refrigerant discharged from the evaporator fails. A control method for an air-conditioning refrigeration apparatus, characterized in that the air-conditioning refrigeration apparatus is led to the inlet of the cascade heat exchanger via the other cooling compressor without going through the cooling compressor.

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