JP6447165B2 - Refrigeration equipment - Google Patents

Description

  The present invention relates to a refrigeration apparatus having a function of performing a heat shock that is effective in maintaining the freshness of stored goods. In particular, the present invention relates to a container refrigeration apparatus that can increase the temperature of stored goods and perform reliable heat shock treatment.

  Conventionally, the heat shock process with respect to the fruit and vegetables which are the stored articles of a nonpatent literature 1 is known. In this non-patent document 1, when strawberry is subjected to high-temperature treatment at 45 ° C. for 4 hours or 35 ° C. for 24 hours and then stored at 1 ° C. for 28 days, rot is suppressed for those not subjected to treatment, and freshness is maintained. It is described that it becomes possible.

  Non-Patent Document 2 also discloses quality improvement of stored fruit by heat stress control.

  Furthermore, Patent Document 1 and Patent Document 2 disclose a two-stage booster type refrigeration apparatus. The two-stage boosting refrigeration cycle used in this two-stage boosting refrigeration apparatus is more efficient and can increase the output as compared with a single-stage ordinary refrigeration cycle.

JP 2012-97936 A JP 2012-255603 A

"Effect of high temperature treatment on quality change during storage of strawberry fruit", Yo Kobayashi, Takuo Hamada, Journal of Japan Society of Low Temperature Preservation VOL. 20, NO. 4. In 1994, “Improvement of stored fruit quality by heat stress control”, Tetsuo Morimoto, Plant Environmental Engineering, Japanese Society of Plant Factory Publication, 20 (4), December 2008, pages 219-227

  However, a refrigeration apparatus having a heat shock processing function utilizing a refrigeration container or the like is not known. Therefore, the utility of heat shock is known, but the control method during operation in the refrigeration apparatus is not known. Further, as described in Non-Patent Document 1, if the temperature and time of the high-temperature treatment are not appropriate, the quality may be deteriorated conversely by performing the treatment.

  An object of this invention is to provide the freezing apparatus which can manage appropriately the temperature and time of a high temperature process in view of the said problem. In particular, when a high-temperature treatment of a stored product is performed using a heating device, a refrigeration apparatus capable of raising the temperature of the stored product to a predetermined temperature up to the core while shortening the temperature range in which bacteria are likely to propagate is provided. The purpose is to do.

  Descriptions of patent documents listed as prior art can be introduced or incorporated by reference as explanations of technical elements described in this specification.

In order to achieve the above object, the present invention employs the following technical means. That is, in this invention, it is provided in the store | warehouse | warehouse | chamber in which stored goods (45) are stored, the heat exchanger for cooling (18) which cools the air in a store | warehouse | chamber, and the heat exchanger for heating (5) which warms the store interior , A compression mechanism (11, 12) for supplying refrigerant to the cooling heat exchanger, a radiator (13) for radiating heat of the refrigerant compressed by the compression mechanism to the outside air, and a cooling heat exchanger (18) A cooling heat exchanger fan (18a) that sucks in air from the inside of the cabinet and passes through the cooling heat exchanger (18), a radiator fan (13a) that guides outside air to the radiator (13), and a stored item ( 45) a stored product temperature detecting means (23, 231) for detecting the temperature, and a control device (20) for controlling the compression mechanism, the cooling heat exchanger fan, and the radiator fan, The inside of the warehouse is blown until the temperature of the stored product temperature detection means reaches the specified temperature. Heating control means (S52, S54, S56) that heats or keeps in at least two stages, the first stage that is not needed and the stage after the inside is warmed at once to prevent the growth of bacteria, and the heated room And refrigeration control means (S57) for cooling the inside . The stage that does not warm up at a stretch is a stage that takes a relatively long time to reach a predetermined temperature and has a small rate of temperature increase. The stage that warms up at a stretch is the time it takes to reach a predetermined temperature compared to the previous stage. Is a stage with a relatively short temperature rise rate.

  According to this invention, since the inside of the cabinet is heated in two stages until the temperature reaches a predetermined temperature based on the detected value of the stored product temperature detecting means for detecting the temperature of the stored product, the temperature of the stored product in the warehouse is accurately reflected. Temperature control becomes possible. Therefore, in the heat shock process with respect to stored goods, the temperature and time of a high temperature process can be managed appropriately. In addition, since the storage stage temperature detection means has a previous stage that does not warm the inside of the warehouse at a stretch until the temperature reaches a predetermined temperature, it can be raised to a predetermined temperature up to the center of the storage product, and can be warmed at a stretch to prevent the growth of bacteria. Since it has a later stage, it is possible to provide a refrigeration apparatus capable of shortening the time in a temperature zone in which bacteria are likely to propagate when performing high-temperature treatment.

  In addition, the code | symbol in parentheses as described in a claim and said each means thru | or description is an example which shows the correspondence with the specific means as described in embodiment mentioned later easily, and limits the content of invention is not.

It is equipment arrangement drawing which cools the inside of the warehouse of the trailer in a 1st embodiment of the present invention. It is an external view of the trailer side surface in the said embodiment. It is a whole block diagram of the 2 step | paragraph pressure | voltage rise refrigerating cycle in the said embodiment. It is a flowchart which shows an example of the refrigeration control process in the said embodiment. It is a flowchart which shows the heat shock process in the said embodiment. It is a flowchart which shows the detail in step S54 of FIG. It is a graph which shows an example of the temperature change characteristic of the heat shock process in the said embodiment. It is an apparatus arrangement | positioning figure in the store | warehouse | chamber in 2nd Embodiment of this invention. It is the equipment arrangement | positioning figure in the store | warehouse | chamber in 3rd Embodiment of this invention. It is apparatus arrangement | positioning drawing in the store | warehouse | chamber in 4th Embodiment of this invention. It is detail drawing of the temperature detection means between stored goods in 4th Embodiment. It is a whole block diagram of the heat pump cycle in 5th Embodiment of this invention. It is a block diagram of the refrigerating cycle in 6th Embodiment of this invention.

  A plurality of modes for carrying out the present invention will be described below with reference to the drawings. In each embodiment, parts corresponding to the matters described in the preceding embodiment may be denoted by the same reference numerals, and redundant description may be omitted. In the case where a part of the configuration is described in each form, the other forms described above can be applied to the other parts of the configuration.

  Not only combinations of parts that clearly indicate that the combination is possible in each embodiment, but also the embodiments are partially combined even if they are not clearly specified unless there is a problem with the combination. It is also possible.

(First embodiment)
(First Embodiment) A first embodiment of the present invention will be described below with reference to FIGS. The external appearance seen from the side of the trailer which refrigerates the stored goods 45 stored in the store | warehouse | chamber is shown in FIG. The inside of the warehouse is inside the container mounted on the trailer. In FIG. 2, the trailer is pulled by the driving vehicle 10d. The refrigeration apparatus main body 10b for cooling the inside of the trailer is provided between the operating vehicle 10d and the container 100 on the trailer. A power supply device 20d is provided in the refrigeration apparatus main body 10b. The generator in the power supply device 20d is rotated by the sub-engine other than the engine that drives the driving vehicle, and the battery is charged. The battery power is used for starting the sub-engine and driving a cooling heat exchanger fan and a radiator fan, which will be described later.

  FIG. 1 shows an arrangement of devices such as a heat exchanger that cools the inside of the container 100, and shows an arrangement viewed from the side of the container 100. In FIG. 1, the return temperature of air returned from the inside of the container 100 is detected by a suction temperature thermistor serving as suction temperature detection means 23 constituting the stored product temperature detection means. The return temperature Tre reflects the temperature of the stored item 45 such as fruits and vegetables stored in the warehouse.

  The air indicated by the arrow Y <b> 31 returning from the interior is sucked into the cooling heat exchanger fan 18 a and passes through the cooling heat exchanger 18. The heat exchanger 18 for cooling is provided in the store | warehouse | chamber in which the stored goods 45 are stored, and cools the air in a store | warehouse | chamber. Therefore, the refrigerant is caused to flow to the cooling heat exchanger 18 by the two compression mechanisms 11 and 12 provided, and the refrigerant is evaporated to cool the air. The air that has passed through the cooling heat exchanger 18 passes through an electric heater that constitutes the heating heat exchanger 5. The heat exchanger 5 for heating warms the inside of a store | warehouse | chamber.

  The pair of compression mechanisms 11 and 12 that supply the refrigerant to the cooling heat exchanger 18 are surrounded by a compressor cover and provided outside the container. Further, a radiator 13 that radiates heat of the refrigerant compressed by the compression mechanisms 11 and 12 to the outside air and a radiator fan 13 a that guides the outside air to the radiator 13 are provided outside the warehouse. The suction temperature detecting means 23 constitutes a stored product temperature detecting means for indirectly detecting the temperature of the stored product 45.

  A control device 20 (FIG. 3) for controlling the compression mechanisms 11 and 12, the cooling heat exchanger fan 18a, the radiator fan 13a, and the heating heat exchanger 5 is provided. In addition, the control apparatus 20 is provided with the heating control means (step S52, step S54, step S56) which heats or keeps the inside of a store | warehouse | chamber, and the refrigeration control means (step S57) which cools the inside of the store | warehouse | chambered or kept warm.

  The suction temperature detection means 23 detects the temperature on the suction side of the cooling heat exchanger fan 18a as shown in FIG. The heating heat exchanger 5 is composed of an electric heater composed of a nichrome wire or a PTC heater, and is provided on the downstream side of the air passing through the cooling heat exchanger 18. The control device 20 controls energization of the electric heater serving as the heat exchanger 5 for heating based on the temperature of the suction temperature detecting means 23.

  Further, as shown in FIG. 1, a duct wall 41 that guides the warm air that has passed through the heat exchanger 5 for heating into the warehouse, and an air outlet 41 a provided at the tip of the duct wall 41 are provided. A blowing temperature detecting means 42 for detecting the temperature of the air blown into the inside is provided. The blowing temperature detection means 42 is comprised from the thermistor which detects the temperature of the air which blows off from the blower outlet 41a.

  Next, the refrigeration cycle will be described. FIG. 3 shows the overall configuration of the two-stage booster refrigeration cycle 10 of the present embodiment. The two-stage booster refrigeration cycle 10 is applied to a refrigeration apparatus that refrigerates the stored items 45 in the container 100, and blown air blown into a warehouse that is a space to be cooled is about −30 ° C. to −10 ° C. It performs the function of cooling to a very low temperature.

First, as shown in FIG. 3, the two-stage booster refrigeration cycle 10 includes two compressors, a high-stage compressor 11a and a low-stage compressor 12a, so that the refrigerant circulating through the cycle is multistage. The pressure is increased. In addition, as this refrigerant | coolant, a normal freon-type refrigerant | coolant (for example, R404A) is employable. It is also possible to employ a CO ₂ as a refrigerant. Furthermore, the refrigerant is mixed with refrigeration oil (oil) for lubricating the sliding parts in the low-stage compressor 12a and the high-stage compressor 11a, and a part of the refrigeration oil is combined with the refrigerant. Cycle through the cycle.

  First, the low-stage compression mechanism 12 includes a low-stage compressor 12a that compresses and discharges a low-pressure refrigerant until it becomes an intermediate-pressure refrigerant, and a low-stage electric motor 12b that rotationally drives the low-stage compressor 12a. It is an electric compressor having. The low-stage compressor 12a is composed of a fixed capacity compressor whose discharge capacity V2 is fixed, and specifically, various types such as a scroll compressor, a vane compressor, a rolling piston compressor, and the like. A compressor can be adopted.

  The low stage side electric motor 12 b is an AC motor whose operation (number of rotations) is controlled by an AC current output from the low stage side inverter 22. The low-stage inverter 22 outputs an alternating current having a frequency corresponding to the control signal output from the control device 20. And by this frequency control, the refrigerant | coolant discharge capability of the low stage side compressor 12a is changed.

  Therefore, in the first embodiment, the low-stage electric motor 12b constitutes a discharge capacity changing unit of the low-stage compressor 12a. Of course, a DC motor may be adopted as the low-stage electric motor 12b, and the rotation speed may be controlled by the control voltage output from the control device 20. Moreover, the suction port side of the high stage side compressor 11a is connected to the discharge port of the low stage side compressor 12a.

  The basic configuration of the high-stage compression mechanism 11 is the same as that of the low-stage compression mechanism 12. Accordingly, the high stage compressor 11a compresses and discharges the intermediate pressure refrigerant discharged from the low stage compressor 12a until it becomes a high pressure refrigerant.

  Further, the high-stage compression mechanism 11 is a fixed-capacity compression mechanism with a fixed discharge capacity V1, and the high-stage electric motor 11b has a rotational speed controlled by an alternating current output from the high-stage inverter 21. Is done. Moreover, the compression ratio of the high stage side compression mechanism 11 and the compression ratio of the low stage side compression mechanism 12 of 1st Embodiment are substantially equivalent.

  The refrigerant inlet side of the condenser which becomes the radiator 13 is connected to the discharge port of the high stage compressor 11a. The radiator 13 is used for heat dissipation by causing heat exchange between the high-pressure refrigerant discharged from the high-stage compressor 11a and the outside air (outside air) blown by the radiator fan 13a to dissipate the high-pressure refrigerant and cool it. It is a heat exchanger.

  The radiator fan 13 a is an electric blower whose rotation speed (amount of blown air) is controlled by a control voltage output from the control device 20. Note that the two-stage booster refrigeration cycle 10 of the first embodiment employs a chlorofluorocarbon refrigerant as the refrigerant and constitutes a subcritical refrigeration cycle in which the high-pressure side refrigerant pressure does not exceed the refrigerant critical pressure. The radiator 13 in one embodiment functions as a condenser that condenses the refrigerant.

  The refrigerant outlet of the radiator 13 is connected to a branching section 14 that branches the flow of the refrigerant that has flowed out of the radiator 13. The branch portion 14 has a three-way joint structure having three inflow / outflow ports, and one of the inflow / outflow ports is a refrigerant inflow port and two of the inflow / outlet ports are refrigerant outflow ports. Such a branch part 14 may be configured by joining pipes, or may be configured by providing a plurality of refrigerant passages in a metal block or a resin block.

  One refrigerant outlet of the branch part 14 is connected to the inlet side of the intermediate pressure expansion valve 15v, and the other refrigerant outlet of the branch part 14 is connected to the inlet side of the high-pressure refrigerant channel 16a of the intermediate heat exchanger 16. . The intermediate pressure expansion valve 15v is a temperature type expansion valve that decompresses and expands the high-pressure refrigerant flowing out of the radiator 13 until it becomes an intermediate-pressure refrigerant.

  More specifically, the intermediate pressure expansion valve 15v has a temperature sensing part arranged on the outlet side of the intermediate pressure refrigerant flow path 16b in the intermediate heat exchanger 16. The degree of superheat of the outlet side refrigerant in the intermediate pressure refrigerant flow path 16b is detected based on the temperature and pressure of the outlet side refrigerant in the intermediate pressure refrigerant flow path 16b. The valve opening (refrigerant flow rate) is adjusted by a mechanical mechanism so that the degree of superheat becomes a predetermined value set in advance. An electronic expansion valve may be used instead of the temperature expansion valve.

  The inlet side of the intermediate pressure refrigerant flow path 16b is connected to the outlet side of the intermediate pressure expansion valve 15v. The intermediate heat exchanger 16 includes an intermediate pressure refrigerant decompressed and expanded by an intermediate pressure expansion valve 15v that flows through the intermediate pressure refrigerant flow path 16b, and the other branch branched by the branching portion 14 that flows through the high pressure refrigerant flow path 16a. Exchanges heat with high-pressure refrigerant.

  Since the temperature of the high-pressure refrigerant is reduced by reducing the pressure, in the intermediate heat exchanger 16, the intermediate-pressure refrigerant flowing through the intermediate-pressure refrigerant channel 16b is heated, and the high-pressure refrigerant flowing through the high-pressure refrigerant channel 16a is cooled. Will be.

  Further, as a specific configuration of the intermediate heat exchanger 16, a plurality of plate-like heat transfer plate members are stacked and the intermediate pressure refrigerant flow path 16b and the high pressure refrigerant flow path 16a are alternately arranged between the heat transfer plate members. The formed one can be used. A plate heat exchanger that exchanges heat between the high-pressure refrigerant and the intermediate-pressure refrigerant through the heat transfer plate can be employed. Moreover, you may employ | adopt the double-tube-type heat exchanger structure which arrange | positions the inner side pipe | tube which forms the intermediate pressure refrigerant flow path 16b inside the outer side pipe | tube which forms the high pressure refrigerant flow path 16a. Of course, the high-pressure refrigerant channel 16a may be an inner tube and the intermediate-pressure refrigerant channel 16b may be an outer tube. Furthermore, the structure etc. which join the refrigerant | coolant piping which forms the high pressure refrigerant flow path 16a and the intermediate pressure refrigerant flow path 16b, and heat-exchange may be employ | adopted.

  In the intermediate heat exchanger 16 shown in FIG. 3, the flow direction of the high-pressure refrigerant flowing through the high-pressure refrigerant flow path 16a and the flow direction of the intermediate pressure refrigerant flowing through the intermediate-pressure refrigerant flow path 16b are the same. A heat exchanger is used. However, a counter flow type heat exchanger in which the flow direction of the high-pressure refrigerant flowing through the high-pressure refrigerant flow path 16a and the flow direction of the intermediate-pressure refrigerant flowing through the intermediate pressure refrigerant flow path 16b are opposite to each other may be employed.

  The inlet side of the high stage compressor 11a is connected to the outlet side of the intermediate pressure refrigerant flow path 16b of the intermediate heat exchanger 16 via a check valve (not shown). Therefore, in the high-stage compression mechanism 11 of the first embodiment, the mixed refrigerant of the intermediate-pressure refrigerant flowing out from the intermediate-pressure refrigerant flow path 16b and the intermediate-pressure refrigerant discharged from the low-stage compressor 12a is sucked.

  On the other hand, the inlet side of the low-pressure expansion valve 17v is connected to the outlet side of the high-pressure refrigerant channel 16a of the intermediate heat exchanger 16. The low-pressure expansion valve 17v is a temperature type expansion valve that decompresses and expands the high-pressure refrigerant flowing out of the radiator 13 until it becomes a low-pressure refrigerant. Instead of this temperature type expansion valve, an electronic type expansion valve that operates with a control signal from the control device 20 may be used. The basic configuration of the low pressure expansion valve 17v is the same as that of the intermediate pressure expansion valve 15v.

  More specifically, the low pressure expansion valve 17v in the case of using a temperature type expansion valve has a temperature sensing part arranged on the refrigerant outlet side of the cooling heat exchanger 18 described later. The temperature sensing part detects the degree of superheat of the refrigerant on the outlet side of the cooling heat exchanger 18 based on the temperature and pressure of the refrigerant on the outlet side of the cooling heat exchanger 18, and the degree of superheat is a predetermined value set in advance. The valve opening is adjusted by a mechanical mechanism so that

  The refrigerant inlet side of the cooling heat exchanger 18 is connected to the outlet side of the low pressure expansion valve 17v. The cooling heat exchanger 18 exchanges heat between the low-pressure refrigerant decompressed and expanded by the low-pressure expansion valve 17v and the blown air circulated through the interior by the cooling heat exchanger fan 18a. This is an endothermic heat exchanger that evaporates to exert an endothermic effect.

  The cooling heat exchanger fan 18 a is an electric blower in which the rotation speed (the amount of blown air) is controlled by a control voltage output from the control device 20. Further, the refrigerant outlet of the cooling heat exchanger 18 is connected to the suction port side of the low stage compressor 12a.

  Next, the control device of the first embodiment will be described. The control device 20 includes a well-known microcomputer including a CPU and storage circuits such as a ROM and a RAM that store programs and data. The control device 20 includes an output circuit that outputs control signals or control voltages to various devices to be controlled, an input circuit that receives detection signals from various sensors, a power supply circuit, and the like.

  On the output side of the control device 20, a low stage side inverter 22, a high stage side inverter 21, a radiator fan 13a, a cooling heat exchanger fan 18a, and the like are connected as control target devices. Control the operation of the target device.

  Note that the control device 20 is configured such that control means for controlling the operation of these controlled devices is integrally formed. The hardware and software which are the structures which control the operation | movement of each control object apparatus among the control apparatuses 20 comprise the control means of each control object apparatus.

  In the present embodiment, the first discharge capacity control unit 20a is configured to control the refrigerant discharge capacity of the low stage compression mechanism 12 by controlling the operation of the low stage inverter 22. And the structure which controls the action | operation of the high stage side inverter 21 and controls the refrigerant | coolant discharge capability of the high stage side compression mechanism 11 is made into the 2nd discharge capability control part 20b.

  Accordingly, the rotation speed of the low-stage side electric motor 12b and the rotation speed of the high-stage side electric motor 11b can be controlled independently of each other by the first discharge capacity control unit 20a and the second discharge capacity control unit 20b, respectively. ing. Of course, you may comprise the 1st, 2nd discharge capability control parts 20a and 20b as a control apparatus separate with respect to the control apparatus 20, respectively.

  On the other hand, on the input side of the control device 20, although not shown, an outside air temperature sensor is provided which is an outside air temperature detecting means for detecting the outside air temperature Tam of outside air (outside air) heat exchanged with the high-pressure refrigerant by the radiator 13. It has been. Further, on the input side of the control device 20, a suction temperature thermistor serving as a suction temperature detecting means 23 which is a temperature detecting means inside the chamber for detecting the return temperature of the return air heat exchanged with the low-pressure refrigerant in the cooling heat exchanger 18. Etc. are connected. Detection signals from these sensors are input to the control device 20.

  Further, an operation panel 30 is connected to the input side of the control device 20. The operation panel 30 is provided with an operation stop switch as request signal output means for outputting an operation request signal or a stop request signal for the refrigeration apparatus. Further, the operation panel 30 is provided with a temperature setting switch or the like as setting temperature setting means for setting the internal temperature (set temperature) Tset. The operation signals of these switches are input to the control device 20. The operation panel 30 is provided in the driver seat inside the driving vehicle 10d in FIG.

  Next, a general operation at the time of internal cooling of the two-stage booster refrigeration cycle 10 of the present embodiment having the above configuration will be described with reference to FIG. Based on FIG. 4, the control of the internal cooling operation which the control apparatus 20 performs is demonstrated. This control process starts when the operation stop switch of the operation panel 30 is turned on (ON) and an operation request signal is output.

  First, in step S1 of FIG. 4, initialization of flags and timers is performed. In the next step S2, a detection signal detected by an outside temperature sensor and a suction temperature thermistor serving as the suction temperature detecting means 23 and an operation signal such as a temperature setting switch of the operation panel 30 are read. And an operation mode is determined according to Tset set by the temperature setting switch. Specifically, if the set temperature Tset is −10 ° C. or higher, a refrigeration mode is performed in which refrigeration is performed at a temperature suitable for suppressing a decrease in freshness of fresh foods, and the set temperature Tset is lower than −10 ° C. In this case, the refrigeration mode is used for freezing.

  Then, it progresses to step S3 of FIG. 4, and determines a control mode. Since the control mode is common to both the chilled mode and the frozen mode, description for each operation mode is omitted. The control mode can be directly specified by the phase, signal or control signal regardless of the set temperature.

  Specifically, in step S3, a temperature deviation ΔT, which is a value obtained by subtracting the set temperature Tset set by the temperature setting switch from the return temperature Tre that is the detected temperature of the suction temperature detecting means 23 read in step S2, is obtained. Used. When this temperature deviation ΔT is larger than a predetermined reference temperature deviation ΔKT, it is determined that a large capacity is necessary. Further, when the temperature deviation ΔT is equal to or smaller than a predetermined reference temperature deviation ΔKT, it is determined that the internal temperature is close to the set temperature Tset and that a detailed capability control is required. To do.

  In most cases, immediately after the start of the refrigeration apparatus, the internal temperature, which is the space to be cooled, is higher than the set temperature Tset. Therefore, in the first embodiment, a value obtained by subtracting the set temperature Tset from the return temperature Tre is used as the temperature deviation ΔT. Of course, the return temperature representing the stored product temperature from the set temperature Tset as a temperature deviation ΔT. You may employ | adopt the absolute value of the value which subtracted Tre.

  If it is determined in step S3 that a large capacity is necessary, the process proceeds to step S4, and operation in the cool-down mode is performed. In step S4, the rotational speeds of the high-stage electric motor 11b and the low-stage electric motor 12b are determined so that the refrigerant discharge capacity of the low-stage compressor 12a and the refrigerant discharge capacity of the high-stage compression mechanism 11 are substantially maximized. .

  In subsequent step S5, the control state of the other control target device in the cool-down mode of the refrigeration apparatus is determined. For example, for the radiator fan 13a and the cooling heat exchanger fan 18a, the number of rotations is determined so that the blowing capacity is substantially maximized, and the process proceeds to step S9.

  On the other hand, if it is determined in step S3 that fine capacity control of the refrigeration apparatus is necessary, the process proceeds to step S6, and the operation in the capacity control mode is performed. In step S6, the refrigerant discharge capacity of the low-stage compressor 12a is determined based on the detection signal and operation signal read in step S2 this time.

  More specifically, in step S6, the rotational speed of the low-stage electric motor 12b, that is, the rotational speed N2 of the low-stage compression mechanism 12 is determined based on the elements of temperature deviation, integration, and differentiation. In the subsequent step S7, the refrigerant discharge capacity of the high-stage compression mechanism 11 is determined based on the refrigerant discharge capacity of the low-stage compressor 12a determined in step S6.

Specifically, in step S7, the rotational speed N1 of the high stage compressor 11a is determined so that the effective volume ratio defined by the following formula F1 becomes a value within a predetermined reference range shown by the following formula F2. To do.
Effective volume ratio = N2 × V2 / N1 × V1 (F1)
1 ≦ N2 × V2 / N1 × V1 ≦ 3 (F2)

  V1 is the discharge capacity of the high stage compressor 11a. N1 is the rotation speed of the high-stage compressor 11a, V2 is the discharge capacity of the low-stage compression mechanism 12, and N2 is the rotation speed of the low-stage compression mechanism 12.

  In a succeeding step S8, the control state of the other device to be controlled is determined. For example, with regard to the radiator fan 13a and the cooling heat exchanger fan 18a, the rotational speed is set so that the blowing capacity increases with the increase in the rotational speed N2 of the low-stage compression mechanism 12 determined in step S6. Is determined, and the process proceeds to step S9.

  Next, in step S9, a control signal is output from the control device 20 to the control target device connected to the output side so that the control state determined in steps S4 to S8 is obtained, and step S10 is performed. Proceed to

  In step S10, when the stop request signal from the operation panel 30 is output to the control device 20, the operation of each control target device is stopped and the entire system of the refrigeration apparatus is stopped. On the other hand, if the stop request signal is not output, the process returns to step S2 after waiting for a predetermined control period τ.

  The operation stop switch of the operation panel 30 is turned on to the operation side. Then, in the two-stage booster refrigeration cycle 10 of FIG. 3, the mixed refrigerant is sucked. Specifically, the high-stage compressor 11a generates a mixed refrigerant of the intermediate-pressure refrigerant discharged from the low-stage compressor 12a and the intermediate-pressure refrigerant flowing out from the intermediate-pressure refrigerant flow path 16b of the intermediate heat exchanger 16. Inhale, compress and discharge.

  Then, the high-temperature and high-pressure refrigerant discharged from the high-stage compressor 11a flows into the radiator 13 and is cooled by exchanging heat with the outside air blown by the radiator fan 13a. The flow of the high-pressure refrigerant that has flowed out of the radiator 13 is branched at the branching section 14. The high-pressure refrigerant that has flowed into the intermediate-pressure expansion valve 15v from the branch portion 14 is decompressed and expanded until it becomes an intermediate-pressure refrigerant.

  At this time, the throttle opening degree of the intermediate pressure expansion valve 15v is adjusted so that the degree of superheat of the intermediate pressure refrigerant passage 16b outlet side refrigerant of the intermediate heat exchanger 16 becomes a predetermined value. Further, the intermediate pressure refrigerant decompressed by the intermediate pressure expansion valve 15v flows into the intermediate pressure refrigerant flow path 16b of the intermediate heat exchanger 16, and flows from the branch portion 14 to the high pressure refrigerant flow path 16a of the intermediate heat exchanger 16. Heat is exchanged with the high-pressure refrigerant that has flowed in and is sucked into the high-stage compressor 11a.

  On the other hand, the high-pressure refrigerant that has flowed from the branch portion 14 into the high-pressure refrigerant flow path 16 a of the intermediate heat exchanger 16 is cooled by the intermediate heat exchanger 16. The high-pressure refrigerant that has flowed out of the high-pressure refrigerant channel 16a flows into the low-pressure expansion valve 17v and is decompressed and expanded until it becomes a low-pressure refrigerant. At this time, the throttle opening degree of the low-pressure expansion valve 17v is adjusted so that the degree of superheat of the refrigerant on the outlet side of the cooling heat exchanger 18 becomes a predetermined value.

  Further, the low-pressure refrigerant decompressed by the low-pressure expansion valve 17v flows into the cooling heat exchanger 18, absorbs heat from the blown air circulated by the cooling heat exchanger fan 18a, and evaporates. As a result, the blown air that is blown into the interior that is the space to be cooled is cooled. The refrigerant that has flowed out of the cooling heat exchanger 18 is sucked into the low-stage compressor 12a.

  Since the two-stage booster refrigeration cycle 10 of the first embodiment operates as described above, an economizer refrigeration cycle can be configured to improve the compression efficiency of the high-stage compression mechanism. The economizer cycle is a cycle in which a part of the high-temperature and high-pressure refrigerant once compressed is decompressed to an intermediate pressure and returned to the compressor, whereby a large refrigeration capacity can be obtained even with a small amount of power.

  Next, the control in the case of performing heat shock processing of, for example, fruits and vegetables that are stored items 45 in the warehouse will be described. Based on FIG. 5 and FIG. 6, the heat shock process in 1st Embodiment is demonstrated.

  In FIG. 5, when the heat shock processing start button is turned on, or when the heat shock processing mode is displayed on the display and the determination button is pressed in the operation mode selection mode, the heat shock processing in step S50 is started. Next, in step S51, the return temperature Tre detected by the thermistor of the suction temperature detecting means 23 is compared with the first predetermined temperature. Since it is relatively difficult to directly detect the temperature of the stored product 45, the return temperature Tre detected by the suction temperature detecting means 23 represents the temperature of the stored product 45. Although the 1st predetermined temperature can be changed with the kind of stored goods 45, in the case of a strawberry, it is set as 25 ° C, for example.

  As a result of comparing the return temperature Tre with the first predetermined temperature, if the return temperature Tre is equal to or higher than the first predetermined temperature (in the case of YES), the process proceeds to the next step S53. On the other hand, when the return temperature Tre is not equal to or higher than the first predetermined temperature (in the case of NO), the blowout temperature heating control in step S52 is executed. That is, while monitoring the temperature returning from the inside of the refrigerator, the temperature is not heated up to the first predetermined temperature as the first stage, but is heated while the temperature is controlled by the blowing temperature detecting means 42. Since the product temperature is cold until the temperature returns to the first predetermined temperature and the temperature rises at a stretch, there is a possibility that only the surface of the stored product will be heated. Heat with temperature ramp.

  In the case of step S52, the electric heater serving as the heating heat exchanger 5 in FIG. 1 is energized and heated with a predetermined temperature gradient. After step S52, the process returns to step S51. When the return temperature Tre reaches the first predetermined temperature of 25 ° C., the return temperature Tre is compared with a high second predetermined temperature in step S53. In the case of strawberries, the second predetermined temperature is 40 ° C., for example.

If the return temperature Tre is not equal to or higher than the second predetermined temperature as a result of comparing the return temperature Tre with the second predetermined temperature in step S53, the process proceeds to step S54. In step S54, suction temperature heating control for increasing the temperature as quickly as possible is executed for the purpose of preventing the bacteria from breeding the stored product 45 while monitoring the suction temperature. In this case, the temperature increase gradient is made steeper than the predetermined temperature gradient in step S52. (See Figure 7)
Details of step S54 in FIG. 5 are shown in FIG. In FIG. 6, after step S54c, the process returns to step S53, and the suction temperature heating control in step S54c is continued until the return temperature Tre becomes equal to or higher than the second predetermined temperature. In step S54a, if the rate of increase to the second predetermined temperature is slower than the predetermined speed, it is determined that there is some abnormality, and the control is abnormally terminated in step S54b. Next, in step S55, it is determined whether or not it has continued for a predetermined time since the blowing temperature heating control in step S56 was started. If the predetermined time has not been continued, the blowing temperature heating control in step S56 is continued.

  If it is determined in step S53 that the return temperature Tre is equal to or higher than the second predetermined temperature as a result of comparing the return temperature Tre with the second predetermined temperature, the process proceeds to step S55. In step S55, it is determined whether or not the high-temperature heating control for heat shock processing in step S56 has passed a predetermined time. The predetermined time is set to 4 hours, for example. As a result of determining whether or not the high temperature heating for heat shock processing has elapsed, if it is determined that the predetermined time has elapsed, the process proceeds to step S57, and the refrigeration operation is started to maintain the original refrigeration temperature of the strawberry. The process goes to the cooling control of the refrigeration container (FIG. 4). In step S56, the internal temperature is adjusted to a predetermined temperature while monitoring the blowout temperature detected by the blowout temperature detecting means 42 that is provided at the blowout port 41a in FIG. Maintain temperature set temperature.

  In step S57, for example, the strawberry is controlled in a freezing container that maintains a refrigeration temperature of + 1 ° C. to −1 ° C., which is the temperature before freezing. When the refrigeration control stop command is issued, the heat shock process of FIG. 5 is terminated in step S58.

  In step S55, it is determined whether or not the high-temperature heating control for heat shock processing in step S56 has passed a predetermined time. As a result, when it is determined that the predetermined time has not elapsed, the blowing temperature heating control in step S56 is continued. For example, in the case of a strawberry, 40 ° C. is maintained.

  In the above control, an example of the temperature change characteristic is shown in FIG. In FIG. 7, the heating set temperature and the second predetermined temperature may be the same temperature. In order to perform a heat shock of the stored item 45 in the warehouse, a heating operation is performed. Until the return temperature rises to the first predetermined temperature, the stored product temperature is cold, and if it is warmed at a high temperature, only the surface may be warmed. For this reason, first, heating is performed by the blowout temperature heating control in step S52. That is, the heating temperature is controlled by monitoring the blowing temperature detected by the blowing temperature detecting means 42. Between the first predetermined temperature and the second predetermined temperature, the temperature is raised as quickly as possible for the purpose of preventing the growth of bacteria. And suction temperature heating control is performed in step S54, monitoring the suction temperature (return temperature) with the suction temperature detection means 23 so that the store 45 may not be heated too much.

  Next, when the second predetermined temperature, which is a temperature at which bacteria can propagate, has passed, in order to prevent damage to the stored item 45 at a high temperature, the blowing temperature control is performed while monitoring the temperature with the blowing temperature detecting means 42 in step S56. For example, 40 ° C. is maintained for a while. And if this heat shock process at high temperature continues for a predetermined time, it automatically shifts to the refrigeration operation of step S57.

  The first predetermined temperature is 10 ° C. to 30 ° C., and the second predetermined temperature is 30 ° C. to 50 ° C.

(Operational effects of the first embodiment)
According to the first embodiment, the interior is heated until the predetermined temperature is reached based on the detected value of the suction temperature detecting means 23 serving as the stored product temperature detecting means for detecting the temperature of the stored product 45. The temperature control that more accurately reflects the temperature of the product 45 becomes possible, and the stored product 45 can be heated. Therefore, in the heat shock process for the stored item 45, the temperature of the high temperature process can be appropriately managed.

  Further, the control device heats at least two stages: a previous stage in which the inside of the storage is not warmed at a stretch until the temperature of the stored product temperature detection means reaches a predetermined temperature, and a stage after the warming is prevented at a stretch to prevent bacterial growth. Therefore, it is possible to prevent the stored product from warming only the surface. It can also be warmed at once to prevent the growth of bacteria. The stage that does not warm at a stretch is a stage where the rate of temperature rise of stored goods is small, and the stage that warms up at a stretch is a stage where the temperature rise rate of stored goods is larger than the previous stage.

  The suction temperature detection means 23 serving as the stored product temperature detection means is constituted by a suction temperature detection means 23 for detecting the temperature on the suction side of the cooling heat exchanger fan 18a and detecting the return temperature. According to this, the temperature on the suction side of the cooling heat exchanger fan 18a that sucks air from the inside of the refrigerator into the cooling heat exchanger 18 and passes the cooling heat exchanger 18 is detected. The temperature can be detected at a position closer to the stored item 45 than the temperature of the suction portion of the vessel 18.

  Moreover, the heat shock process of the stored goods 45 conveyed in the container 100 can be performed, and the temperature management of the stored goods 45 stored in the store | warehouse | chamber of the container 100 can be performed correctly.

  Furthermore, according to the first embodiment, it is possible to cool the inside of the warehouse with high output or high efficiency by using the two-stage boosting refrigeration cycle. Moreover, the temperature of the air blown out in the store | warehouse | chamber can be correctly controlled by controlling electricity supply to the electric heater which comprises the heat exchanger 5 for heating.

  Furthermore, the heating control means comprising step S52 and step S54 raises the temperature by dividing the interior into two stages. Thereby, it can heat to the core of the stored goods 45, and can improve the heat shock effect.

  Specifically, until the return temperature rises to the first predetermined temperature, the temperature of the stored item 45 is cold, and if it is warmed at once, only the surface may be warmed. For this reason, first, the temperature is raised to the first predetermined temperature, and the temperature is raised at a stretch to the second predetermined temperature higher than the first predetermined temperature as the second stage. Thereby, only the surface is not warmed, and the temperature of the entire stored item 45 can be raised as much as possible for the purpose of preventing the propagation of bacteria and the like.

  In addition, when the return temperature rises to the first predetermined temperature and exceeds the temperature at which the bacteria can propagate, the first predetermined temperature is monitored while monitoring the suction temperature by suction temperature control in order to prevent damage to the stored item 45 at a high temperature. The temperature is increased to a second predetermined temperature that is higher than the temperature. Therefore, propagation of bacteria and the like can be prevented.

  Next, if the second predetermined temperature is not reached in step S53, the rate of increase to the second predetermined temperature is slow, and if it takes too long, if it is determined in step S54a, the heating process is stopped in step S54b and abnormal. It has ended. As a result, it is possible to prevent deterioration in quality due to insufficient heat shock at high temperatures. This abnormal end eliminates the possibility that the heat shock is not sufficiently performed when the temperature increase rate is slower than a predetermined rate (1 minute to 10 minutes / 1 ° C. increase), and conversely the quality of the stored product 45 is deteriorated. Due to this abnormal end, the heat treatment is stopped, and the process proceeds to the refrigeration operation in step S57 of FIG.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. In the following embodiments, the same components as those in the first embodiment described above are denoted by the same reference numerals, description thereof is omitted, and different configurations will be described. In addition, about 2nd Embodiment or less, the same code | symbol as 1st Embodiment shows the same structure, Comprising: The description which precedes is used.

  The arrangement of the equipment in the warehouse according to the second embodiment of the present invention will be described with reference to FIG. In the second embodiment, an electric heater serving as the heating heat exchanger 5 is provided in the vicinity of the cooling heat exchanger 18 on the downstream side of the cooling heat exchanger 18. Moreover, the 2nd electric heater used as the 2nd heating heat exchanger 46 is being fixed to the floor surface of a container, for example. The second heating heat exchanger 46 is energized by a control device and is equipped with a blower. The second heating heat exchanger 46 is installed at a position closer to the stored item than the heating heat exchanger 5.

(Operational effect of the second embodiment)
According to the second embodiment, since the second heating heat exchanger 46 is provided at a position closer to the stored item 45 than the installation position of the heating heat exchanger 5 close to the cooling heat exchanger 18, The stored product 45 can be heated more quickly.

(Third embodiment)
Next, a third embodiment of the present invention will be described. In the first embodiment, the volume inside the storage for storing the stored item 45 is controlled to be constant. However, in order to increase the efficiency of heating and refrigeration, a partition device 47 such as a curtain is installed between the space where the stored item 45 is placed and the other space to reduce the volume of the space for heating or refrigeration. May be. As such a partition device 47, a well-known device can be used, but the outline is as follows.

  FIG. 9 shows device arrangement in the container 100 according to the third embodiment. In FIG. 9, it has the rail 48 for a movement attached to the center of the ceiling. A partition curtain rail 49 as a moving means for moving in the moving rail 48 is provided. With the movement of the partition curtain rail 49, the curtain serving as the partition device 47 moves. This curtain partitions the container 100. The moving rail 48 and the partition curtain rail 49 are arranged so as to cross in a cross shape. And it is comprised so that the curtain hanging tool which suspended the curtain may slide in the curtain rail 49 for partitions. In addition, the rail 48 for a movement may be provided facing both sides of the container 100 ceiling part.

(Operational effect of the third embodiment)
In the third embodiment, the interior of the container 100 is partitioned by a curtain serving as a partition device 47, and one of the partitioned storage is heated by the heating heat exchanger 5 or the second heating heat exchanger 46. Is done. According to this, since the inside of a store | warehouse | chamber is divided with the curtain used as the partition apparatus 47, the volume of the space to heat can be reduced and the range which controls temperature can be narrowed, Therefore Heating and cooling are attained more rapidly. In particular, in the case of the container 100, various stored items 45 may be mixed and the internal volume is large. Therefore, it is partitioned by a curtain which becomes the partition device 47, and one of the partitioned warehouses is heated or cooled. According to this, since the volume of the space to be heated or cooled can be reduced and the temperature control range can be narrowed, more effective temperature control becomes possible.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described. FIG. 10 shows the equipment arrangement in the warehouse of the fourth embodiment. In FIG. 10, the temperature inside the storage is controlled using the inter-storage temperature detecting means 231 that is installed in the storage product 45 or in a position close to the storage product 45 and detects the temperature of the storage product 45. ing. That is, the inter-stored product temperature detecting means 231 is a temperature detecting means that is installed at least adjacent to the stored product 45 and directly detects the temperature of the stored product 45.

  According to this, the temperature of the stored item 45 can be accurately detected. FIG. 11 shows the details of the inter-stored product temperature detection means 231 that is installed in or near the stored product 45 and detects the temperature of the stored product 50. An inter-stored temperature detecting means 231 comprising a sheath thermocouple is inserted in the fruits and vegetables to be stored 50 or between the stored products 50. The sheath thermocouple is a special thermocouple in which an ultrafine heat-resistant metal protective tube (sheath) is filled with a stable ceramic such as magnesium at a high pressure. This thermocouple has a very thin outer diameter and high flexibility, and there is no fear of disconnection. In addition, the machine density is extremely high, and it has a long service life to prevent corrosion of the thermocouple wire by metal gas or atmospheric gas, and it can withstand high temperature and high pressure. Furthermore, the response to temperature changes is fast. Therefore, accurate temperature control can be realized by directly detecting the temperature of fruits and vegetables.

(Operational effect of the fourth embodiment)
According to the fourth embodiment, the temperature of the stored product 45 is set based on the inter-stored product temperature detection means 231 that is installed inside or adjacent to the stored product 45 and detects the temperature of the stored product 45, for example, a sheath thermocouple. Can be detected more accurately.

(Fifth embodiment)
Next, a fifth embodiment of the present invention will be described. In the previous first embodiment, the inside of the cabinet is heated by the electric heater that becomes the heat exchanger 5 for heating, but this fifth embodiment uses the use side heat that becomes the radiator 13 (condenser) of the heat pump cycle. The inside of the cabinet is heated by the heat of the exchanger 15. This heat pump cycle can use the thing of patent document 2, for example.

  Based on FIG. 12, the heating mode which heats especially the inside of the heat pump cycle of 5th Embodiment is demonstrated. FIG. 12 shows the overall configuration of the heat pump cycle 10h of the fifth embodiment. The heat pump cycle 10h includes an operation in a heating operation mode (heating operation mode) for heating the blown air blown into the interior of the container 100 that is an air-conditioning target space, and a cooling operation mode (refrigeration operation mode) for cooling the blown air. ) Can be switched.

  FIG. 12 shows the refrigerant circuit in the heating operation mode of the heat pump cycle 10h, and the refrigerant flow in this operation mode is indicated by arrows. In the heat pump cycle 10h of this embodiment, a normal chlorofluorocarbon refrigerant (for example, R134a, R407c) is adopted as the refrigerant, and the pressure of the high-pressure side refrigerant of the cycle exceeds the critical pressure of the refrigerant in any operation mode. There is no subcritical refrigeration cycle. Further, the refrigerant is mixed with refrigeration oil (oil) for lubricating the sliding portions in the compressors 11a and 12a, and a part of the refrigeration oil circulates in the cycle together with the refrigerant.

  As shown in FIG. 12, the heat pump cycle 10h includes a low-stage compressor 12a and a high-stage compressor 11a as compressors that compress and discharge the refrigerant. These compressors 11a and 12a have the same basic configuration. Specifically, the high stage side compressor 11a is an electric compressor that drives the fixed capacity type compression mechanism 11 by the high stage side electric motor 11b. The low-stage compressor 12a is an electric compressor that drives the fixed capacity type compression mechanism 12 with a low-stage electric motor 12b.

  As these compression mechanisms 11, 12, various compression mechanisms such as a scroll-type compression mechanism, a vane-type compression mechanism, and a rolling piston-type compression mechanism can be employed. The high-stage electric motor 11b and the low-stage electric motor 12b are AC motors whose operation (number of rotations) is controlled by an AC current output from a dedicated inverter (not shown). The operation of these inverters is controlled by a control signal output from the control device 20.

  And these refrigerant | coolants discharge capability of the compression mechanisms 11 and 12 is changed because these inverters control the rotation speed of the high stage side electric motor 11b and the low stage side electric motor 12b. Of course, DC motors may be employed as the high-stage electric motor 11b and the low-stage electric motor 12b.

  Further, a first four-way valve 131v serving as a refrigerant circuit switching means for switching between the refrigerant circuit in the cooling operation mode and the refrigerant circuit in the heating operation mode is connected to the refrigerant discharge port of the low-stage compressor 12a. A second four-way valve 141v as similar refrigerant circuit switching means is connected to the refrigerant discharge port of the high-stage compressor 11a.

  The first four-way valve 131v switches between a refrigerant circuit for heating operation mode (a circuit indicated by an arrow in FIG. 12) and a refrigerant circuit for cooling operation mode. The second four-way valve 141v functions to switch between a refrigerant circuit for heating operation mode and a refrigerant circuit for cooling operation mode. The operations of the first four-way valve 131v and the second four-way valve 141v are controlled by a control signal output from the control device.

  The use-side heat exchanger 15 used for heating the interior as a radiator in the heating mode forms an air passage for blown air that is blown toward the vehicle interior by the use-side heat exchanger fan 15a. And the refrigerant | coolant which distribute | circulates the inside of the utilization side heat exchanger 15 and ventilation air are heat-exchanged. The use side heat exchanger 15 acts as a condenser and is used to heat the inside of the refrigerator instead of the heating heat exchanger 5 of FIG. Of course, you may use together the use side heat exchanger 15 which acts as a condenser, and the heat exchanger 5 for a heating.

  Specifically, in the heating operation mode, the use side heat exchanger 15 functions as a radiator that heats the refrigerant discharged from the high stage compressor 11a with the blown air to dissipate heat and heats the interior. . In the cooling operation mode, the use side heat exchanger 15 functions as a cooling heat exchanger that evaporates the refrigerant sucked into both the compressors 11a and 12a by exchanging heat with the blown air. The use-side heat exchanger fan 15a is an electric blower whose operation is controlled by a control voltage output from the control device.

  One refrigerant inlet / outlet of the first branch portion 141 that branches the flow of the refrigerant flowing out of the use side heat exchanger 15 is connected to the outlet side of the use side heat exchanger 15 in the heating operation mode. The first branch portion 141 has a three-way joint structure having three refrigerant outlets. Such a 1st branch part 141 may join and comprise piping, and may provide and provide a some refrigerant path in a metal block or a resin block.

  An intermediate pressure refrigerant passage 16b of the intermediate heat exchanger 16 is connected to another refrigerant inlet / outlet of the first branch portion 141 via an intermediate pressure expansion valve 15v, and a high pressure of the intermediate heat exchanger 16 is connected to another refrigerant inlet / outlet. A refrigerant channel 16a is connected.

  The intermediate pressure expansion valve 15v is a decompression unit (first decompression unit) that decompresses the high-pressure refrigerant that has flowed out of the use-side heat exchanger 15 in the heating operation mode until it becomes an intermediate-pressure refrigerant. Specifically, the intermediate pressure expansion valve 15v includes a valve body configured to be able to change the throttle opening degree and an electric actuator including a stepping motor that changes the throttle opening degree of the valve body. It is an electric expansion valve. The operation of the intermediate pressure expansion valve 15v is controlled by a control signal output from the control device.

  Further, the intermediate pressure expansion valve 15v fully closes the throttle opening, thereby blocking the refrigerant flow in the refrigerant passage from the first branch portion 141 to the inlet side of the intermediate pressure refrigerant flow path 16b. The circuit can be switched.

  Therefore, the intermediate pressure expansion valve 15v of the present embodiment functions as a decompression unit and also functions as a refrigerant circuit switching unit. In the present embodiment, the throttle opening of the intermediate pressure expansion valve 15v is fully closed during the cooling operation mode.

  The intermediate heat exchanger 16 includes an intermediate pressure refrigerant decompressed by an intermediate pressure expansion valve 15v that circulates in the intermediate pressure refrigerant flow path 16b in the heating operation mode, and a first branch portion 141 that circulates in the high pressure refrigerant flow path 16a. Heat exchange is performed with the branched high-pressure refrigerant. Since the temperature of the high-pressure refrigerant is reduced by reducing the pressure, in the intermediate heat exchanger 16, the intermediate-pressure refrigerant flowing through the intermediate-pressure refrigerant channel 16b is heated, and the high-pressure refrigerant flowing through the high-pressure refrigerant channel 16a is cooled. Is done.

  One refrigerant inlet / outlet of the first junction 19g is connected to the outlet side of the intermediate pressure refrigerant flow path 16b of the intermediate heat exchanger 16 in the heating operation mode. The basic configuration of the first merging portion 19g is the same as that of the first branching portion 141, and one refrigerant inlet / outlet of the first four-way valve 131v is connected to another refrigerant inlet / outlet of the first merging portion 19g. The refrigerant inlet / outlet port is connected to the inlet side of the high stage compressor 11a.

  As a result, during the heating operation mode, the intermediate pressure refrigerant flowing out from the intermediate pressure refrigerant flow path 16b flows into the first merging portion 19g, and the intermediate pressure refrigerant discharged from the low-stage compressor 12a is transferred to the first merging portion 19g. And flows out to the suction port side of the high stage compressor 11a. On the other hand, in the cooling operation mode, the low-pressure refrigerant that has flowed out of the accumulator 23a flows into the first merging portion 19g via the first four-way valve 131v, and flows out to the suction port side of the high-stage compressor 11a.

  Next, the inlet side of the low-pressure expansion valve 17v is connected to the outlet side of the high-pressure refrigerant flow path 16a of the intermediate heat exchanger 16 in the heating operation mode. The low pressure expansion valve 17v depressurizes the high pressure refrigerant flowing out from the high pressure refrigerant flow path 16a in the heating operation mode until it becomes a low pressure refrigerant, and in the cooling operation mode until the high pressure refrigerant flowing out from the outdoor heat exchanger 210 becomes the low pressure refrigerant. A decompression means (second decompression means) for decompressing.

  The basic configuration of the low pressure expansion valve 17v is the same as that of the intermediate pressure expansion valve 15v. Therefore, the low-pressure expansion valve 17v is configured to include a valve body that can change the throttle opening degree and an electric actuator that changes the throttle opening degree of the valve body. The operation is controlled by the signal.

  An outdoor heat exchanger 210 is connected to the outlet side of the low pressure expansion valve 17v in the heating operation mode. The outdoor heat exchanger 210 is arranged outside the warehouse, and exchanges heat between the refrigerant circulating inside and the outdoor air (outside air) blown by the outdoor heat exchanger fan 21a outside the warehouse.

  Specifically, in the heating operation mode, the outdoor heat exchanger 210 functions as a cooling heat exchanger that functions as an evaporator that heats and evaporates the refrigerant sucked into the low-stage compressor 12a with the outside air. . In the cooling operation mode, the outdoor heat exchanger 210 functions as a radiator that causes the refrigerant discharged from both the first compressors 11a and 12a to exchange heat with the outside air to dissipate heat. The outdoor heat exchanger fan 21a is an electric blower whose operation is controlled by a control voltage output from the control device.

  Furthermore, one refrigerant inlet / outlet of the second junction 22g is connected to the outlet side of the outdoor heat exchanger 210 in the heating operation mode. The basic configuration of the second merging portion 22g is the same as that of the first merging portion 19g. One refrigerant inlet / outlet of the second four-way valve 141v is connected to another refrigerant inlet / outlet of the second merging portion 22g, and one of the first four-way valves 131v is connected to another refrigerant inlet / outlet via the check valve 25. The refrigerant inlet / outlet is connected.

  Thereby, in the heating operation mode, the low-pressure refrigerant that has flowed out of the outdoor heat exchanger 210 flows into the second merging portion 22g, and flows out to the accumulator 23a side through the second four-way valve 141v. In the cooling operation mode, the high-pressure refrigerant discharged from the low-stage compressor 12a flows into the second junction 22g via the first four-way valve 131v. At the same time, the high-pressure refrigerant discharged from the low-stage compressor 12a flows into the second junction 22g via the second four-way valve 141v and flows out to the outdoor heat exchanger 210 side.

  The accumulator 23a is a gas / liquid separation means for separating the gas / liquid of the refrigerant flowing into the accumulator 23a. One refrigerant inlet / outlet of the second branch portion 141b is connected to the gas phase refrigerant outlet side of the accumulator 23a. The basic configuration of the second branch portion 141b is the same as that of the first branch portion 141, and the refrigerant inlet side of the low-stage compressor 12a is connected to another refrigerant inlet / outlet of the second branch portion 141b. An upstream side of the check valve 25 is connected to the refrigerant inlet / outlet.

  The check valve 25 is a valve means for allowing the refrigerant to flow from one refrigerant outlet side (upstream side) of the first four-way valve 131v to the refrigerant inlet side of the accumulator 23a and the outdoor heat exchanger 210 side (downstream side). It is. Thereby, in the heating operation mode, the refrigerant flowing out of the outdoor heat exchanger 210 is prevented from flowing into the gas-phase refrigerant outlet side of the accumulator 23a through the first four-way valve 131v. In the cooling operation mode, the refrigerant discharged from the low stage compressor 12a is allowed to flow out to the outdoor heat exchanger 210 side via the first four-way valve 131v.

  Next, the control apparatus 20 of 5th Embodiment is demonstrated. The control device 20 includes a known microcomputer, an output circuit, an input circuit to which detection signals from various sensors are input, a power supply circuit, and the like.

  On the output side of the control device 20, the inverters for the compressors 11a and 12a, the first four-way valve 131v, the second four-way valve 141v, the use-side heat exchanger fan 15a, the intermediate pressure expansion valve 15v, the low pressure expansion valve 17v, An outdoor heat exchanger fan 21a and the like are connected. The control device 20 controls the operation of these control target devices. A part of the wiring between the control device 20 and the control target device is not shown.

  The structure which controls the refrigerant | coolant discharge capability of the compression mechanism 11 by controlling the action | operation of the inverter for the high stage side electric motor 11b comprises the 1st discharge capability control means. The configuration for controlling the refrigerant discharge capability of the compression mechanism 12 by controlling the operation of the inverter for the low-stage side electric motor 12b constitutes the second discharge capability control means.

  Accordingly, the rotation speeds of the high-stage electric motor 11b and the low-stage electric motor 12b, that is, the refrigerant discharge capacities of the compression mechanisms 11 and 12, are independent of each other by the first discharge capacity control means and the second discharge capacity control means, respectively. Can be controlled.

  Further, the refrigerant circuit switching is configured to control the operation of the first four-way valve 131v, the second four-way valve 141v, and the intermediate pressure expansion valve 15v to switch between the refrigerant circuit in the heating operation mode and the refrigerant circuit in the cooling operation mode. It constitutes a control means. Of course, the first and second discharge capacity control means and the refrigerant circuit switching control means may be configured as separate control devices for the control device 20, respectively.

  Further, an operation panel 30 (FIG. 2) provided at the driver's seat is connected to the input side of the control device 20. The operation panel 30 is provided with an operation stop switch for outputting an operation request signal or a stop request signal to the control device 20, a set temperature setting switch for setting a set temperature Tset in the cabinet, and the operation signals of these switches. Is input to the control device 20.

  Further, as described above, the heat pump cycle 10h of the fifth embodiment can be switched between the operation in the heating operation mode and the operation in the cooling operation mode. The operation in the heating operation mode is executed when the inside of the warehouse is heated.

  Specifically, in the heating operation mode, the control device 20 is connected between the refrigerant outlet side of the low stage compressor 12a and the refrigerant inlet side of the high stage compressor 11a and the gas phase refrigerant outlet side of the accumulator 23a. And the upstream side of the check valve 25 are connected simultaneously. Specifically, the operation of the first four-way valve 131v is controlled. Further, the second four-way valve 141v is connected so as to simultaneously connect between the refrigerant discharge port side of the high stage compressor 11a and the use side heat exchanger 15 and between the outdoor heat exchanger 210 and the refrigerant inlet side of the accumulator 23a. Control the operation of

  Further, the control device 20 controls the operation of the intermediate pressure expansion valve 15v and the low pressure expansion valve 17v so that the respective throttle openings become predetermined predetermined openings. Thereby, it changes to the refrigerant circuit through which a refrigerant flows, as shown by the solid line arrow of FIG.

  In the heating operation mode, the low-stage compressor 12a and the high-stage compressor 11a are connected in series to boost the refrigerant in multiple stages. Then, the intermediate pressure refrigerant decompressed by the intermediate pressure expansion valve 15v joins with the refrigerant discharged from the low stage compressor 12a and is sucked into the high stage compressor 11a. Thereby, what is called an economizer-type refrigeration cycle is comprised and the heating in a warehouse is implement | achieved.

  Next, the operation in the cooling operation mode is executed when the inside of the refrigerator is refrigerated. Specifically, in the cooling operation mode, the control device 20 is connected between the refrigerant discharge port side of the low-stage compressor 12a and the upstream side of the check valve 25, and the gas-phase refrigerant outlet side and the high-stage side of the accumulator 23a. The compressor 11a is connected to the refrigerant inlet side at the same time. For this purpose, the operation of the first four-way valve 131v is controlled, between the refrigerant discharge port side of the high stage compressor 11a and the outdoor heat exchanger 210, and between the use side heat exchanger 15 and the refrigerant inlet side of the accumulator 23a. Are connected simultaneously. For this purpose, the operation of the second four-way valve 141v is controlled.

  Furthermore, the control device 20 controls the operation of the low pressure expansion valve 17v so that the intermediate pressure expansion valve 15v is fully closed and the throttle opening degree of the low pressure expansion valve 17v becomes a predetermined opening degree. And the refrigerant | coolant compressed until it became a high voltage | pressure refrigerant | coolant with the low stage side compressor 12a flows in into the 2nd junction part 22g via the 1st four-way valve 131v and the check valve 25. Furthermore, the refrigerant compressed until it becomes a high-pressure refrigerant in the high-stage compressor 11a flows into the second junction 22g via the second four-way valve 141v. Further, the refrigerant discharged from both compressors 11a and 12a joins at the second joining portion 22g.

  The high-pressure refrigerant merged at the second merging portion 22g flows into the outdoor heat exchanger 210 and radiates heat by exchanging heat with the outside air blown by the outdoor heat exchanger fan 21a. The high-pressure refrigerant that has flowed out of the outdoor heat exchanger 210 is decompressed by the low-pressure expansion valve 17v until it becomes low-pressure refrigerant, and flows into the high-pressure refrigerant flow path 16a of the intermediate heat exchanger 16.

  Here, in the cooling operation mode, the intermediate pressure expansion valve 15v is fully closed, so that no refrigerant flows into the intermediate pressure refrigerant channel 16b of the intermediate heat exchanger 16. Therefore, the intermediate heat exchanger 16 in the cooling operation mode does not exchange heat between the refrigerants, and the high-pressure refrigerant flow path 16a functions as a simple refrigerant passage.

  Further, the flow of the low-pressure refrigerant that has flowed out of the high-pressure refrigerant flow path 16 a of the intermediate heat exchanger 16 flows into the use-side heat exchanger 15 without being branched at the first branch portion 141. The low-pressure refrigerant flowing into the use side heat exchanger 15 absorbs heat from the blown air blown from the use side heat exchanger fan 15a and evaporates. Thereby, blowing air is cooled and cooling in a store | warehouse | chamber is implement | achieved.

  The low-pressure refrigerant that has flowed out of the use side heat exchanger 15 flows into the accumulator 23a via the second four-way valve 141v and is separated into gas and liquid. The flow of the low-pressure refrigerant that has flowed out of the gas-phase refrigerant outlet of the accumulator 23a is branched at the second branch portion 141b. One branched low-pressure refrigerant is sucked into the low-stage compressor 12a and compressed again, and the other branched low-pressure refrigerant is sucked into the high-stage compressor 11a via the first four-way valve 131v and compressed again. Is done.

  According to the heat pump cycle 10h of the fifth embodiment, in the cooling operation mode, a normal refrigeration cycle in which the low-stage compressor 12a and the high-stage compressor 11a are connected in parallel is configured, and the internal cooling is performed. Realized.

  Accordingly, in any of the operation modes, the two compressors of the high stage compressor 11a and the low stage compressor 12a can exhibit the refrigerant discharge capability. Thereby, the air blown into the vehicle interior, which is the heat exchange target fluid, can be efficiently heated or cooled in comparison with the case where one compressor exerts the refrigerant discharge capability.

  Furthermore, an economizer refrigeration cycle using the intermediate heat exchanger 16 is configured in the heating operation mode. Accordingly, the refrigeration cycle 10 can exhibit high cycle efficiency (COP). At the same time, the intermediate pressure refrigerant decompressed by the intermediate pressure expansion valve 15v can be heated and vaporized, and liquid compression of the high stage compressor 11a can be prevented.

  In the cooling operation mode, the two compressors 11a and 12a are connected in parallel. Therefore, the refrigerant | coolant flow capacity Gr which distribute | circulates the utilization side heat exchanger 15 is increased with respect to the case where the two compressors 11a and 12a are connected in series, and the heat absorption capacity | capacitance of the refrigerant | coolant in the utilization side heat exchanger 15 ( A decrease in the cooling capacity of the blown air can be suppressed.

  Further, in the heat pump cycle 10h, in the heating operation mode, the compressors 11a and 12a are connected in series to switch to an economizer refrigeration cycle that compresses refrigerant in multiple stages. Therefore, the cycle efficiency improvement effect by reducing the compression ratio of the compressors 11a and 12a can be efficiently obtained.

(Operational effects of the fifth embodiment)
In the fifth embodiment, the heat exchanger for heating that heats the inside of the cabinet is composed of a radiator 13 that constitutes a use side heat exchanger 15 that generates heat in a heat pump cycle. The control device 20 controls the compressors 11a and 12a constituting the heat pump cycle based on the return temperature of the stored product temperature detecting means or the blowing temperature of the blowing temperature detecting means 42. Moreover, when cooling the inside of a store | warehouse | chamber, the evaporator 18 which comprises the utilization side heat exchanger 15 is utilized.

  According to this, the inside of a store | warehouse | chamber can be heated efficiently, the inside of a store | warehouse | chamber is heated, the heat_generation | fever of the radiator of a heat pump cycle is controlled based on the temperature which reflected or estimated the temperature of the stored goods 45.

(Sixth embodiment)
In the above embodiment, the two-stage boosting refrigeration cycle is used, but the inside of the refrigerator may be heated or cooled by using two normal refrigeration cycles using a single compressor. FIG. 13 shows the configuration of the refrigeration cycle of the sixth embodiment. The control device 20 controls the compression mechanism 11 of the first refrigeration cycle 101 and the compression mechanism 12 of the second refrigeration cycle 102. When the interior is cooled, the interior air is circulated through the cooling heat exchanger 18 of the first refrigeration cycle 101 for cooling. When the interior is heated, the interior air is circulated through the condenser serving as the radiator 13 of the second refrigeration cycle 102 to heat the interior. The second refrigeration cycle 102 is dedicated to heating, and the first refrigeration cycle 101 is dedicated to cooling. The heat exchanger 18 for cooling in the second refrigeration cycle cools the outside as an outdoor heat exchanger and pumps up heat from the outside air.

(Other embodiments)
In the above embodiment, the preferred embodiment of the present invention has been described. However, the present invention is not limited to the above embodiment, and various modifications can be made without departing from the gist of the present invention. It is. The structure of the said embodiment is an illustration to the last, Comprising: The scope of the present invention is not limited to the range of these description. The scope of the present invention is indicated by the description of the scope of claims, and further includes meanings equivalent to the description of the scope of claims and all modifications within the scope.

  In the above embodiment, the cycle configuration employing the intermediate heat exchanger 16 has been described, but the cycle configuration of the two-stage booster type refrigeration apparatus of the present invention is not limited to this. For example, the intermediate heat exchanger 16 may be abolished, and an intermediate gas-liquid separator that separates the gas-liquid refrigerant flowing out from the sub-expansion valve may be provided.

  Then, the gas-phase refrigerant separated by the intermediate gas-liquid separator may be sucked into the high-stage compressor 11a. In this case, the secondary (intermediate pressure) expansion valve may be eliminated, and instead, a fixed throttle or a solenoid valve circuit that selects a refrigerant passage passing through the fixed throttle may be employed. Therefore, in the present invention, the sub-expansion valve includes these alternative means.

  Further, the branching unit 141 may be eliminated, and the liquid phase refrigerant separated by the intermediate gas-liquid separator may be allowed to flow into the low pressure expansion valve 17v so as to constitute an economizer refrigeration apparatus.

  In the above embodiment, separate drive means are adopted for each of the compressors 11a and 12a. However, both the high-stage compressor 11a and the low-stage compressor 12a are configured using one electric motor as the drive means. May be driven. Further, an engine (internal combustion engine) may be employed as the driving means. In addition to the induction motor, a motor that rotates the compressor of the electric compressor may use a DC brushless motor to further increase the efficiency.

  Moreover, although it heated by 2 stages, you may divide and control in 3 stages or more. In short, it is only necessary to heat up the core and quickly raise the temperature in order to suppress the growth of bacteria and keep the raised temperature.

  Furthermore, in the first embodiment, the container refrigeration apparatus is mounted on the trailer. However, this is merely an example, and the application of the present invention is not limited to the container refrigeration apparatus mounted on the trailer. The present invention may be applied to a container refrigeration apparatus in which a single container is placed at a fixed position, or a container cooling apparatus mounted on a container ship. Of course, the refrigeration apparatus main body is not limited to the power supply in the trailer but may be operated by an external power supply. For example, on a container ship, power is supplied from the onboard switchboard.

5, 15 Heat exchanger for heating 11a, 12a Compressor 13 Radiator 15 Use-side heat exchanger that also serves as a radiator 18 Heat exchanger for cooling 23 Suction temperature detection means 23, 231 Stored product temperature detection means 42 Blowout temperature detection means 46 Second Heat Exchanger 210 Outdoor Heat Exchanger

Claims (13)

A cooling heat exchanger (18) for cooling the air in the storage provided in the storage for storing the stored items (45);
A heat exchanger for heating (5) for heating the inside of the cabinet;
A compression mechanism (11, 12) for supplying a refrigerant to the cooling heat exchanger;
A radiator (13) that radiates heat of the refrigerant compressed by the compression mechanism to the outside air;
A cooling heat exchanger fan (18a) that sucks air from the inside of the warehouse into the cooling heat exchanger (18) and passes the cooling heat exchanger (18);
A radiator fan (13a) for guiding the outside air to the radiator (13);
Storage product temperature detection means (23, 231) for detecting the temperature of the storage product (45);
A control device (20) for controlling the compression mechanism, the cooling heat exchanger fan, and the radiator fan;
The control device includes:
Heating is divided into at least two stages: a previous stage in which the inside of the storage is not warmed at a stretch until the temperature of the stored product temperature detection means reaches a predetermined temperature, and a stage after the interior is warmed at once to prevent the growth of bacteria. Or heating control means for keeping warm (S52, S54, S56),
And a refrigeration control means (S57) for cooling the heated interior. The first predetermined temperature related to the previous stage that does not warm the interior at once is 10 ° C. to 30 ° C.,
The second predetermined temperature related to the subsequent stage for preventing the growth of bacteria by warming the inside at once is 30 ° C. to 50 ° C.,
2. The refrigeration apparatus according to claim 1, wherein, when the detected temperature exceeds the second predetermined temperature, the heating control unit maintains the second predetermined temperature while monitoring the blowing temperature. The heating control means includes
While raising the temperature in a predetermined temperature gradient while monitoring the blowing temperature until the temperature detected by the stored product temperature detecting means (23, 231) reaches the first predetermined temperature with the inside as the first stage,
Raising the temperature in the chamber while monitoring the suction temperature with a temperature gradient steeper than the predetermined temperature gradient until the second predetermined temperature, which is higher than the first predetermined temperature, is set as the second stage in the chamber. The refrigeration apparatus according to claim 2. Furthermore, a duct wall (41) that guides the warm air that has passed through the heat exchanger for heating (5) into the warehouse, and an air outlet (41a) provided at the tip of the duct wall (41) are provided. ,
The outlet (41a) is provided with a blowing temperature detecting means (42) for detecting the blowing temperature of the air blown into the warehouse,
4. The refrigeration apparatus according to claim 3, wherein the inside of the refrigerator is heated to the first predetermined temperature while monitoring the temperature detected by the blowing temperature detecting means (42).   The refrigeration apparatus according to any one of claims 1 to 4, wherein the inside of the warehouse is inside a container (100).   The interior of the warehouse is partitioned by a partition device (47), and one of the partitioned warehouses is heated and controlled by the heating control means. The refrigeration apparatus described.   7. The compression mechanism (11, 12) is provided in two sets, and the inside of the refrigerator is cooled by the refrigeration control means by a two-stage boosting refrigeration cycle. Refrigeration equipment.   The refrigeration apparatus according to any one of claims 1 to 7, wherein when the rate of temperature rise in the chamber is slower than a predetermined rate, the heating process is stopped and the control is abnormally terminated. Furthermore, in the said store | warehouse | chamber, the 2nd heating heat exchanger (46) is provided in the position closer to the said store (45) than the installation position of the said heat exchanger for heating (5),
The refrigeration apparatus according to any one of claims 1 to 8, wherein the second heating heat exchanger (46) is controlled by the heating control means of the control device (20). The cooling heat exchanger (18) is composed of a heat pump cycle use side heat exchanger (15) serving as an evaporator,
The radiator (13) is composed of an outdoor heat exchanger (210) of the heat pump cycle,
The cooling heat exchanger fan (18a) is composed of a use side heat exchanger fan (15a),
The radiator fan (13a) is composed of an outdoor heat exchanger fan (21a) for guiding the outside air to the outdoor heat exchanger (210).
The refrigeration apparatus according to any one of claims 1 to 9, wherein the heating heat exchanger (5) includes the use-side heat exchanger (15) that generates heat in the heat pump cycle. . The supplies temperature detecting means (23) of claims 1 to 10, characterized in that the return temperature detecting means for detecting the an intake side of the air temperature of the cooling heat exchanger (18) return temperature The refrigeration apparatus according to any one of the above. The stored product temperature detecting means (231) is a temperature detecting means that is installed in or adjacent to the stored product (45) and directly detects the temperature of the stored product (45). The refrigeration apparatus according to any one of 1 to 10 . The supplies temperature detecting means (23), according to claim 1 to 10, characterized in that it is constituted from said cooling heat exchanger fan suction temperature detecting means (23) for detecting the temperature of the suction side (18a) The refrigeration apparatus according to any one of the above.

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