JP2019191841A - Temperature controller for warm/cold storage - Google Patents

Abstract

To provide a temperature controller for a warm/cold storage capable of precisely managing temperature while suppressing temperature change.SOLUTION: A temperature controller for a warm/cold storage 1 having a housing S in which a chamber for storing articles is formed, a first freezing circuit 31 which cools the inside of the chamber and an electric heater 20 which heats the inside of the chamber, comprises: a chamber temperature sensor 51 for detecting internal temperature of the chamber; an operation device 30 for setting a target reaching temperature inside the chamber and a target time to reach the target reaching temperature; and a control unit 50 for executing chamber precision temperature control to control the first freezing circuit 31 and the electric heater 20, so as to reach the target reaching temperature at the time of reaching the target time by, on the basis of the internal temperature of the chamber and the target time, calculating a set temperature gradient of the internal temperature of the chamber to change the internal temperature of the chamber by a constant set temperature gradient.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a temperature control technique for a hot and cold storage for storing articles.

  In the hot / cold storage that holds the interior at an arbitrary temperature, a heating device such as an electric heater and an evaporator of the cooling device are arranged in the storage, and the interior can be heated and cooled. In such a hot and cold storage, the temperature in the storage is detected, the operation of the heating device and the cooling device is controlled so as to become the set temperature, and the gradient operation for changing the interior to the set temperature or the storage Equilibrium operation is performed to maintain the inside at the set temperature.

  For example, in Patent Document 1, the expansion mechanism of the cooling device includes a variable opening expansion mechanism, and the cooling device is operated continuously, while controlling the opening of the expansion mechanism and the output of the heating device to perform gradient operation and equilibrium operation. I do.

  In Patent Document 2, the cooling device is ON / OFF controlled so as to suppress deviation from the set temperature gradient during the gradient operation.

JP-A-2-229556 JP-A-3-218803

  However, precise temperature management is required to maintain equilibrium operation in a slight temperature range, such as a thermostatic chamber or a research / reservoir used for research, and to further suppress deviation from the set temperature gradient even in gradient operation. Yes.

  In such a temperature-controlled refrigerator that requires precise temperature management, the temperature control methods of Patent Document 1 and Patent Document 2 described above can maintain temperature accurately in a narrow range in equilibrium operation, or in gradient operation. It is difficult to suppress a deviation from the set temperature gradient and smoothly change the temperature.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a temperature control device for a heating / cooling chamber capable of precise temperature management while suppressing deviation from a set temperature gradient. And

In order to solve the above problems, a temperature control device for a hot and cold storage according to the present invention includes a housing in which a storage room for storing articles is formed, a cooling device for cooling the interior of the storage room, A heating / cooling chamber temperature control device having a heating device for heating the interior of the storage room, the internal temperature detector for detecting the internal temperature of the storage room, and a target temperature inside the storage room A target temperature setting section to be set;
Based on the target time setting unit for setting the target time until the target temperature is reached, the internal temperature of the storage room, the target temperature, and the target time, a set temperature gradient of the internal temperature of the storage room is calculated. The internal precision temperature control for controlling the cooling device and the heating device so as to reach the target temperature when the target time is reached by changing the internal temperature of the storage room at a constant set temperature gradient. And a control unit to be executed.

  Preferably, the control unit includes an intrusion heat amount calculation unit that calculates an intrusion heat amount per unit time from the outside to the inside of the storage room, and from the outside of the storage room during execution of the precise temperature control in the storage room. A maximum intrusion heat amount calculation unit for calculating the maximum intrusion heat amount per unit time into the interior, and in the internal precise temperature control, the difference between the maximum intrusion heat amount and the intrusion heat amount is determined by the heating device. Supplement with warming.

  Preferably, the control unit controls the cooling device so as to cool the interior of the storage room with a predetermined amount of cooling heat per unit time in the internal precision temperature control, and the intrusion heat amount and the cooling heat amount. And the warming amount per unit time heated by the warming device is the amount of heat necessary to change the temperature of the interior of the warehouse with the set temperature change amount. To control.

  Preferably, an outside air temperature detector that detects an external temperature of the storage room is provided, and the intrusion heat amount calculation unit adds a surface area of the housing and a predetermined coefficient to a difference between the internal temperature and the external temperature of the storage room. Then, the intrusion heat amount is calculated.

  Preferably, the cooling device performs evaporation temperature control for controlling the evaporation temperature of the refrigerant flowing into the evaporator in the refrigeration cycle, or superheat degree control for controlling the superheat degree of the refrigerant flowing out of the evaporator, The control unit executes additional value control for correcting the target temperature based on a difference between an actual temperature gradient of the internal temperature of the warehouse and the set temperature gradient.

  Preferably, the heating device circulates a heat medium through an electric heater disposed inside the warehouse and a pipe disposed in the casing so as to cover the circumference of the warehouse. At least one of the brine facilities to be heated.

  Preferably, the controller is configured to reduce the internal temperature to an intermediate target temperature with a temperature gradient larger than the set temperature gradient when reducing the internal temperature of the warehouse to the target temperature, and An equilibrium cooling mode for maintaining an internal temperature at the intermediate target temperature for a predetermined time and a slow cooling mode for decreasing the internal temperature from the intermediate target temperature to the target temperature are sequentially executed, and at least the slow cooling mode In the above, the internal precision temperature control is executed.

  According to the present invention, the cooling device and the heating device are controlled to change the internal temperature of the storage room to the target temperature with a constant temperature gradient over the target time, so that the temperature of the article stored inside the storage room is Deviation from the set temperature gradient can be suppressed, and the state of the article can be maintained.

  In addition, by operating both the cooling device and the heating device, it is possible to change the temperature of the interior of the storage room constantly with a small amount of temperature change.

It is a schematic perspective view of the hot and cold storage which employ | adopts the temperature control apparatus of one Embodiment of this invention. It is a block diagram of the freezing circuit and control system in the hot / cold storage of this embodiment. It is a flowchart which shows a part of temperature control point of a temperature cold storage. It is a flowchart which shows the remaining part of the temperature control point of a temperature cold storage.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  The hot and cold storage 1 that employs the temperature control device of the present embodiment is used as, for example, a thermostatic chamber or a medicine storage that requires precise temperature management.

  FIG. 1 is a schematic perspective view of the hot and cold storage of the present invention.

  The hot / cold storage 1 is comprised from the storage part S arrange | positioned at the lower part, and the machine part M arrange | positioned at the upper part.

  The storage unit S includes an outer box 10 (housing) that is a rectangular parallelepiped housing having a front opening, and an outer door 11 for closing the front opening of the outer box 10. Each of the doors 11 has a structure filled with a heat insulating material.

  The outer door 11 opens and closes the front opening of the outer box 10 by rotating around a hinge (not shown) attached to the front surface of the left or right side wall toward the outer box 10.

  Inside the outer box 10 is provided an inner box 12 (storage room) for storing articles. Between the inner box 12 and the outer box 10, a duct 13 for circulating the air in the warehouse (in the storage unit S) is provided. The duct 13 is provided behind and above the inner box. The duct 13 above the inner box 12 has an electric heater 20 as a heating device for heating the inside of the cabinet, and a first cooling device which will be described later as a cooling device for cooling the inside of the cabinet. The internal evaporator 21 (evaporator) of the refrigeration circuit 31 and the second refrigeration circuit 32 and the fan 22 are provided. The duct 13 communicates the opening 23 at the lower end of the rear part of the inner box 12 and the opening 24 at the upper front end. In the duct 13 above the inner box 12, an internal evaporator 21, a fan 22, and an electric heater 20 are arranged in this order from the rear to the front. By the operation of the fan 22, the air in the duct 13 passes through the internal evaporator 21 and the electric heater 20, is reflected on the inner wall surface of the outer door 11, and flows into the inner box 12 from the opening 24. Then, the air in the inner box 12 is sucked into the duct 13 through the opening 23 and returns to the internal evaporator 21 to circulate in the storage unit S.

  Further, on the front surface of the machine part M, an operating device 30 for setting a target attainment temperature (target temperature) in the cabinet, a required (arrival) time (target time) that is a time required to reach the target attainment temperature, and the like. (Target temperature setting unit, target time setting unit). The controller device 30 can set a plurality of sets of target arrival temperatures and required (arrival) times. Based on the plurality of sets of target arrival temperatures and required (arrival) times, temperature control in the cabinet is sequentially performed. Is possible.

  FIG. 2 is a configuration diagram of a refrigeration circuit and a control system in the hot / cold storage 1.

  The hot / cold storage 1 of this embodiment is provided with the 1st freezing circuit 31 and the 2nd freezing circuit 32 as a cooling device which cools the inside of a store | warehouse | chamber.

  The first refrigeration circuit 31 is a refrigeration cycle having a refrigerant circulation path 33, and the second refrigeration circuit 32 is a refrigeration cycle having a refrigerant circulation path 34. The circulation path 33 and the circulation path 34 are configured independently of each other. As the refrigerant, for example, both the first refrigeration circuit 31 and the second refrigeration circuit 32 use HFC-134a.

  The circulation path 33 of the first refrigeration circuit 31 includes a compressor 35, a condenser 36, an electronic expansion valve 37, an internal evaporator 21, and an external evaporator 38 in order in the refrigerant flow direction.

  On the other hand, the circulation path 34 of the second refrigeration circuit 32 includes a compressor 40, a condenser 41, an electronic expansion valve 42, and an internal evaporator 21 in order in the refrigerant flow direction.

  Since each of the compressors 35 and 40, the condensers 36 and 41, the electronic expansion valves 37 and 42, and the internal evaporator 21 in each refrigeration circuit 31 and 32 is a known configuration, a detailed description of the structure and function is provided. Is omitted.

  Further, the first refrigeration circuit 31 is provided with a hot gas defrosting circuit 45. The hot gas defrosting circuit 45 includes a flow path switching electromagnetic valve 46 disposed in the circulation path 33 between the compressor 35 and the condenser 36, a branch from the electromagnetic valve 46, and an electronic expansion valve 37 and a warehouse. The communication path 47 communicates with the circulation path 33 between the inner evaporator 21 and the inner evaporator 21.

  In normal times, the solenoid valve 46 is switched so that all the refrigerant discharged from the compressor 35 flows into the condenser 36. In the hot gas defrosting circuit 45, for example, the user operates the electromagnetic valve 46 by operating the operation device 30, and guides the refrigerant that has been compressed by the compressor 35 and has reached a high temperature to the internal evaporator 21 through the communication path 47. Thus, the internal evaporator 21 is heated to remove frost in the internal storage.

  The compressors 35 and 40, the condensers 36 and 41, the electronic expansion valves 37 and 42, and the outside evaporator 38 are arranged in the machine part M. The internal evaporator 21 is arranged inside the outer box 10, that is, in the storage unit S as described above.

  In the internal evaporator 21, the refrigerant circulation paths 33 and 34 are disposed independently of each other. However, all or part of other components such as fins are made common to the first refrigeration circuit. 31 and the 2nd freezing circuit 32 are comprised integrally.

  The external evaporator 38 has a smaller capacity than the internal evaporator 21. The external evaporator 38 exchanges heat between the refrigerant that has passed through the internal evaporator 21 and the outside air, and evaporates the refrigerant that could not be evaporated in the internal evaporator 21. Thereby, the temperature of the refrigerant returning to the compressor 35 can be stably increased, and the suction temperature of the compressor 35 can be stabilized.

  That is, the first refrigeration circuit 31 can be stably operated even with a small cooling capacity as compared with the second refrigeration circuit 32 that does not have the external evaporator 38.

  Inside the inner box 12 of the hot and cold storage 1 is provided with an internal temperature sensor 51 (internal temperature detector) for detecting the internal temperature (internal temperature of the internal chamber), and the machine part M has an outside air temperature (external temperature). An outside temperature sensor 52 (outside temperature detector) for detecting the outside temperature of the room is provided.

  Each of the first refrigeration circuit 31 and the second refrigeration circuit 32 is provided with evaporation temperature sensors 53a and 53b that detect the refrigerant temperature as the refrigerant evaporation temperature at the inlet of the internal evaporator 21, and Superheat degree sensors 54a and 54b for detecting the refrigerant temperature as the degree of superheat of the refrigerant are provided at the outlet of the inner evaporator 21.

  The machine unit M is provided with a control unit 50 (control unit, intrusion heat amount calculation unit, maximum ingress heat amount calculation unit) that controls the operation of the hot and cold storage 1. The control unit 50 is a control device for performing comprehensive control of the heating / cooling chamber 1, and includes an input / output device, a storage device (ROM, RAM, nonvolatile RAM, etc.), a central processing unit (CPU), a clock, and a timer. Etc. are configured. The control unit 50 inputs various temperatures detected from the inside temperature sensor 51, the outside air temperature sensor 52, the evaporation temperature sensors 53a and 53b, and the superheat degree sensors 54a and 54b, and also inputs operation information from the operation device 30. The electronic expansion valves 37 and 42 and the electric heater 20 are operated and controlled.

  The control unit 50 performs cooling of the interior by the first refrigeration circuit 31 and the second refrigeration circuit 32 and heating of the interior by the electric heater 20, and further includes the first refrigeration circuit 31, the second refrigeration circuit 32, and At least one of the electric heaters 20 is subjected to additional value control to perform precise temperature control (in-house accurate temperature control).

  For cooling in the cabinet, either or both of evaporation temperature control and superheat degree control are employed.

  In the evaporation temperature control, the electronic expansion valves 37 and 42 are controlled such that the refrigerant evaporation temperature detected by the evaporation temperature sensors 53a and 53b approaches the target evaporation temperature. Moreover, superheat degree control controls the electronic expansion valves 37 and 42 so that the superheat degree of the refrigerant | coolant detected by the superheat degree sensors 54a and 54b approaches the target superheat degree. Since the evaporation temperature control and the superheat degree control are known techniques, detailed description thereof is omitted.

  The control unit 50 has three cooling modes, namely, a rapid cooling mode, which is a kind of gradient operation, an equilibrium cooling mode, which is a kind of equilibrium operation, and a slow cooling mode, which is a kind of gradient operation, when performing cooling control of the inside of the refrigerator. Is possible.

  In the rapid cooling mode, both the first refrigeration circuit 31 and the second refrigeration circuit 32 are operated to reach an intermediate target temperature (intermediate target temperature) (for example, 4 ° C.). The intermediate target temperature is, for example, several degrees higher than the target temperature. In the rapid cooling mode, it is desirable to employ superheat control.

  In the equilibrium cooling mode, the operation of the second refrigeration circuit 32 is stopped, and only the first refrigeration circuit 31 is operated. Here, the system is operated for a predetermined time so as to equilibrate (maintain) the evaporation temperature to the intermediate target temperature. In the equilibrium cooling mode, it is desirable to employ evaporation temperature control.

  In the slow cooling mode, after the equilibrium cooling mode, the temperature is gradually lowered from the intermediate target temperature to the target temperature (for example, −5 ° C.). The intermediate target temperature is, for example, several degrees higher than the target temperature.

  If the internal temperature rises greatly due to opening / closing of doors or installation of new cooling objects, the rapid cooling mode → equilibrium cooling mode → slow cooling mode are executed in this order, and the target temperature reached After reaching, the equilibrium cooling mode is executed.

  When the internal temperature is slightly higher than the target temperature (for example, less than 1 ° C.), the slow cooling mode is executed.

  FIG. 3 is a flowchart showing a part of the temperature control procedure of the heating / cooling chamber 1 executed in the control unit 50. FIG. 4 is a flowchart showing the remainder of the temperature control procedure of the hot / cold storage 1 executed in the control unit 50.

  The temperature control (in-chamber precise temperature control) of the present embodiment shown in FIGS. 3 and 4 is executed in each of the above cooling modes.

  First, in step S10, the target temperature and the required time are input and set in the operating device 30. Then, the process proceeds to step S20.

  In step S20, a temperature gradient (set temperature gradient) is calculated based on the target reached temperature and required time input in step S10 and the current internal temperature detected from the internal temperature sensor 51. The temperature gradient is a set temperature change amount per unit time when the temperature is constantly changed from the internal temperature to the target temperature, and is obtained by dividing the temperature difference between the internal temperature and the target temperature by the required time. Then, the process proceeds to step S30.

In step S30, the estimated maximum intrusion heat amount Pmax is calculated. The estimated maximum intrusion heat amount Pmax is the maximum amount of heat that enters the interior from the outside per unit time until the interior temperature reaches the target temperature, that is, during the execution of the interior precise temperature control. Value. The estimated maximum intrusion heat Pmax is the difference between the assumed outside air temperature and the assumed inside temperature at the time when the difference between the outside air temperature and the inside temperature becomes the largest (for example, the outside air temperature and the inside temperature at the start of this control) Difference) ΔTmax is calculated using the following equation (1).
Pmax = K × A × ΔTmax (1)

  K is an inherent constant determined by the degree of heat insulation of the hot / cold storage 1, and A is the surface area of the hot / cold storage 1. Therefore, K × A is a specific coefficient (predetermined coefficient) of the hot / cold storage 1 and uses a value measured in advance by an experiment or the like. Then, the process proceeds to step S40. The control of this step in the control unit 50 corresponds to the maximum intrusion heat amount calculation unit of the present invention.

  In step S40, the outside temperature sensor 52 detects and inputs the current outside temperature. Then, the process proceeds to step S50.

  In step S50, the current internal temperature is detected and input by the internal temperature sensor 51. Then, the process proceeds to step S60.

  In step S60, the target temperature in the cabinet is set, and the setting time is started. The target temperature is a target temperature after a predetermined time for additional value control (for example, 2 minutes) set for additional value control, which will be described later, and additional value control is performed using the temperature gradient calculated in step S20 from the current internal temperature. The internal temperature after the elapse of a predetermined time is calculated. Then, the process proceeds to step S70.

In step S70, the current estimated intrusion heat amount P2 is calculated from the current outside air temperature input in step S40 and the current internal temperature input in step S50. The current estimated intrusion heat amount P2 is calculated by using the following equation (2) from ΔT which is a temperature difference between the current outside air temperature and the current inside temperature.
P2 = K x A x ΔT (2)
Then, the process proceeds to step S80. The control of this step in the control unit 50 corresponds to the intrusion heat amount calculation unit of the present invention.

  In step S80, the insufficient heat quantity P1 is calculated. The insufficient heat quantity P1 is obtained by subtracting the current estimated intrusion heat quantity P2 calculated in step S70 from the estimated maximum intrusion heat quantity Pmax calculated in step S30. That is, the insufficient heat quantity P1 is calculated so as to satisfy the relationship of Pmax = P1 + P2. Further, the heat quantity P3 is calculated by adding the heat quantity corresponding to the temperature gradient calculated in step S20 to the calculated heat quantity P1. Then, the process proceeds to step S90.

  In step S90, the duty ratio of the electric heater 20 is calculated so as to output the insufficient heat amount P3 obtained by adding the temperature gradient calculated in step S80. Specifically, the duty ratio of the energization current of the electric heater 20 is calculated so as to output the insufficient heat amount P3 with respect to the maximum heating capacity of the electric heater 20. Then, the process proceeds to step S100.

  In step S100, the duty ratio calculated in step S90 is corrected by adding a correction value for additional value control calculated in step S150 described later. Then, the process proceeds to step S110 in FIG.

  In step S110, the electric heater 20 is energized with the duty ratio corrected in step S100. Then, the process proceeds to step S120.

  In step S120, the internal temperature is detected by the internal temperature sensor 51, and it is determined whether or not the current internal temperature has reached the target temperature set in step S60. If the target temperature has been reached, the process proceeds to step S130. If the target temperature has not been reached, the process returns to step S40.

  In step S <b> 130, the internal temperature is detected by the internal temperature sensor 51, and it is determined whether or not the current internal temperature has reached the target reached temperature set in the operation unit 30. If the target temperature is reached, this routine is terminated. If the target temperature has not been reached, the process proceeds to step S140.

  In step S140, it is determined whether or not a predetermined time for additional value control has elapsed since the start of timing in step S60. The predetermined time for additional value control is a value that is appropriately set for additional value control. The additional value control is feedback control (PID control) for matching the internal temperature with the target temperature, and is executed by calculating a temperature gradient in step S150 and correcting the duty ratio in step S100. This additional value control is performed, for example, based on the difference between the average value of the chamber internal temperature detected 10 times in 4 seconds and the average value in the previous 4 seconds. If a predetermined time for additional value control has elapsed, the process proceeds to step S150. If the predetermined time for additional value control has not elapsed, the process returns to step S40.

  In Step S150, a correction temperature (gradient) for additional value control is calculated. In this step, even if the predetermined time set in step S60 has elapsed, the inside of the refrigerator has not reached the target temperature, so the duty ratio of the electric heater 20 is set to a value that is appropriately increased. Then, the process returns to step S40.

  As described above, in the hot / cold storage 1 of the first embodiment, since the first refrigeration circuit 31 includes the internal evaporator 21 and the external evaporator 38, it is stable even if the refrigeration capacity is a low value. Can be activated. Thereby, the temperature fluctuation at the time of cooling with the 1st freezing circuit 31 can be controlled.

  Further, in the first refrigeration circuit 31, the refrigerant can be evaporated in the outside evaporator 38 even if the refrigerant is not sufficiently evaporated in the inside evaporator 21. Therefore, the refrigerating capacity into the store | warehouse | chamber by the 1st freezing circuit 31 can be made small. Thus, by cooling by the first refrigeration circuit 31, for example, after reaching the target temperature, the inside of the refrigerator is slightly cooled to stabilize the temperature in a narrow range, or from a set temperature gradient. It is suitable for the rapid cooling mode and the slow cooling mode in which the deviation of the temperature is suppressed and the temperature is smoothly changed.

  Moreover, since the 2nd freezing circuit 32 does not have the outside evaporator 38, when a big cooling capability is required, it can cool efficiently. Therefore, when the difference between the internal temperature and the set temperature is large, the internal temperature can be cooled more rapidly than the first refrigeration circuit 31. Furthermore, when the difference between the internal temperature and the set temperature is large, both the first refrigeration circuit 31 and the second refrigeration circuit 32 can secure a larger cooling capacity.

  Moreover, since the electric heater 20 is provided, the air circulating in the interior can be heated with a desired amount of heat with high responsiveness. Thereby, while the inside of a store | warehouse | chamber can be heated rather than external temperature, the temperature inside the store | warehouse | chamber can be precisely managed by operating simultaneously with the 1st freezing circuit 31 also when cooling.

  In particular, in the hot / cold storage according to the present embodiment, as shown in FIGS. 3 and 4, the operation device 30 sets the target temperature that is the target temperature in the storage and the time required to reach the target temperature. The temperature gradient, which is the amount of temperature change per unit time, is calculated from these settings.

  Then, the estimated maximum intrusion heat amount Pmax that enters the interior is calculated from the current inside temperature until the required time elapses, and the first capacity is exhibited so as to exhibit a cooling capacity that is equal to or greater than the estimated maximum intrusion heat amount Pmax. The refrigeration circuit 31 is controlled. Since the estimated maximum intrusion heat amount Pmax becomes large when the difference between the internal temperature and the outside air temperature is the largest, for example, the intrusion heat amount at the start of temperature control is calculated to obtain the estimated maximum intrusion heat amount Pmax.

  Although the internal temperature changes due to the internal heating or cooling, the amount of heat entering the internal storage changes, the current internal temperature that is sequentially detected while controlling the cooling capacity of the first refrigeration circuit 31 to be constant. The amount of heat entering the interior calculated based on the outside air temperature, the amount of cooling heat of the first refrigeration circuit 31 and the amount of heat of the electric heater 20 are offset, and the interior temperature changes by a temperature gradient. The amount of heat of the electric heater 20 is controlled. By controlling in this way, the internal temperature can be changed with a set constant temperature gradient regardless of the temperature change in the internal space due to cooling or heating. Therefore, it can suppress that the temperature of the stored item in a warehouse deviates from the set temperature gradient, and the influence by the temperature change to the stored item in a warehouse can be suppressed.

  In addition, since the output of the first refrigeration circuit 31 having a relatively low temperature change responsiveness is made constant and the output of the electric heater 20 having a good temperature change responsiveness is controlled, the responsiveness is maintained even when the interior is cooled. It becomes possible to control the temperature well and precisely.

  Moreover, in this embodiment, three modes, rapid cooling mode, equilibrium cooling mode, and slow cooling mode, are possible. For example, when the current internal temperature is 20 ° C. and the target attainment temperature is −5 ° C., 4 ° C. set before the target attainment temperature is set as the intermediate target attainment temperature, and cooling is first performed in the rapid cooling mode. Then, the operation is performed in the slow cooling mode from the intermediate target temperature to the target temperature. In addition, even if it cools quickly to 4 ° C in the rapid cooling mode, the effect on the stored items is relatively minor, and when it is cooled from 4 ° C to -5 ° C, it will be overcooled above 0 ° C. Therefore, a gradual temperature change by the slow cooling mode is required.

  At the time of switching between the rapid cooling mode in which cooling is performed by the first refrigeration circuit 31 and the second refrigeration circuit 32 and the slow cooling mode in which cooling is performed only by the first refrigeration circuit 31, the evaporator temperature is different from the intermediate target temperature. There may be a temperature. Therefore, by providing an equilibrium cooling mode between the rapid cooling mode and the slow cooling mode, the evaporator temperature is once converged to the intermediate target temperature, and the temperature change when shifting to the slow cooling mode is suppressed. Can do.

  Also, when measuring the current internal temperature, for example, it is measured 10 times in 4 seconds, and temperature control is performed using the difference between the average value and the previous average value. Suppressing and precise temperature control becomes possible.

  In the above embodiment, in the equilibrium cooling mode and the slow cooling mode (especially in the case of a small temperature difference for a long time), the required cooling capacity by the first refrigeration circuit 31 cancels out intrusion heat and the like. In this case, for example, the cooling speed of the first refrigeration circuit 31 may be further reduced by reducing the rotational speed of the compressor 35. As a result, it is possible to maintain the internal temperature while reducing power consumption, and to secure a temperature gradient when cooling the internal space.

  In the above embodiment, the equilibrium cooling mode for keeping the internal temperature constant may be controlled with the temperature gradient set to zero.

  Moreover, in the said embodiment, although the inside of a store | warehouse | chamber is warmed with the electric heater 20, instead of the electric heater 20, the piping etc. which provided between the inner box 12 and the outer box 10 so that the inner box 12 may be covered are brine etc. A brine facility for circulating the heat medium may be provided to heat the interior. Alternatively, the interior may be heated by both the electric heater 20 and the brine facility. When the heating device by the brine facility is provided as described above, the amount of heat entering the cabinet by the brine facility is added to control the amount of heat entering the cabinet to be constant. Thereby, it becomes possible to control the amount of heat entering the cabinet more precisely and constantly.

  Note that the target time may be set instead of setting the required time (target time) in the controller device 3 of the above embodiment. In this case, the control unit 50 may calculate the required time (target time) by calculating the difference between the current time and the target time.

  In addition, the hot and cold storage of the present invention is widely applied not only to the thermostatic bath and the storage of medicines as in the above embodiment, but also to the hot and cold storage that requires precise temperature control such as aging of environmental test equipment and meat. Can do.

1 Hot and cold storage 10 Outer box (housing)
20 Electric heater (heating device)
21 Internal evaporator (evaporator)
30 operating devices (target temperature setting unit, target time setting unit)
31 First refrigeration circuit (cooling device)
50 control units (control unit, intrusion heat amount calculation unit, maximum ingress heat amount calculation unit)
51 Internal temperature sensor (Internal temperature detector)
52 Outside temperature sensor (outside temperature detector)

Claims (7)

The temperature of the hot and cold refrigerator having a housing in which a warehouse for storing articles is formed, a cooling device for cooling the interior of the warehouse, and a heating device for heating the interior of the warehouse. A control device,
An internal temperature detector for detecting the internal temperature of the storage room;
A target temperature setting unit for setting a target temperature inside the storage room;
A target time setting unit for setting a target time until the target temperature is reached;
Based on the internal temperature of the storage room, the target temperature, and the target time, a set temperature gradient of the internal temperature of the storage room is calculated, and the internal temperature of the storage room is changed at a constant set temperature gradient. And a controller that performs precise internal temperature control for controlling the cooling device and the heating device to reach the target temperature when the target time is reached,
A temperature control device for a hot / cold storage, comprising: The controller is
An intrusion heat amount calculation unit for calculating an intrusion heat amount per unit time from the outside to the inside of the storage room;
A maximum intrusion heat amount calculation unit for calculating a maximum intrusion heat amount per unit time from the outside to the inside of the storage room during execution of the internal precision temperature control,
2. The temperature control device for a heating / cooling chamber according to claim 1, wherein, in the internal precision temperature control, a difference between the maximum amount of intrusion heat and the amount of intrusion heat is compensated by heating by the heating device. The controller is
In the internal precision temperature control, the cooling device is controlled so as to cool the interior of the storage room with a predetermined cooling heat amount per unit time, and the intrusion heat amount, the cooling heat amount, and the heating device unit time. The heating device is controlled so that the sum of the amount and the amount of heating heat per unit is the amount of heat necessary to change the temperature of the interior of the warehouse with the set temperature gradient. The temperature control device of the hot and cold storage described. An outside temperature detector for detecting the outside temperature of the storage room;
The intrusion heat amount calculation unit calculates the intrusion heat amount by adding the surface area of the housing and a predetermined coefficient to the difference between the internal temperature and the external temperature of the storage room. The temperature control device of the hot and cold storage described. The cooling device is subjected to evaporation temperature control for controlling the evaporation temperature of the refrigerant flowing into the evaporator in the refrigeration cycle, or superheat degree control for controlling the superheat degree of the refrigerant flowing out of the evaporator,
The said control part performs the additional value control which correct | amends the said target temperature based on the difference of the actual temperature gradient of the internal temperature of the said chamber, and the said setting temperature gradient. 5. The temperature control device for a heating / cooling chamber according to any one of 4 above.   The heating device heats the warehouse by circulating a heat medium through an electric heater arranged inside the warehouse and a pipe arranged in the housing so as to cover the circumference of the warehouse. The temperature control device for a hot / cold storage according to any one of claims 1 to 5, wherein the temperature control device is at least one of the brine facilities. The controller is configured to reduce the internal temperature to an intermediate target temperature with a temperature gradient larger than the set temperature gradient when reducing the internal temperature of the storage room to the target temperature, and the internal temperature. An equilibrium cooling mode for maintaining the intermediate target temperature for a predetermined time and a slow cooling mode for decreasing the internal temperature from the intermediate target temperature to the target temperature are sequentially executed.
The temperature control device for a hot / cold storage according to any one of claims 1 to 6, wherein the internal precise temperature control is executed at least in the slow cooling mode.

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