CN108351143B

CN108351143B - Storage device

Info

Publication number: CN108351143B
Application number: CN201680064084.2A
Authority: CN
Inventors: 绿川麿
Original assignee: Denso Corp
Current assignee: Denso Corp
Priority date: 2015-11-04
Filing date: 2016-10-11
Publication date: 2020-03-10
Anticipated expiration: 2036-10-11
Also published as: JP2017089919A; WO2017077818A1; CN108351143A; JP6406214B2

Abstract

The storage device is provided with a storage room temperature sensor (31) and a control unit (50). A temperature sensor (31) in the storage chamber detects the temperature in the storage chamber. The control unit (50) controls the driving of a cooling device (20) that cools the storage chamber on the basis of the set temperature. The control unit (50) has a temperature threshold set to a temperature higher than a set temperature, and when the temperature in the storage chamber is equal to or higher than the temperature threshold, the control unit (50) executes cooling control for driving the cooling device (20) to rapidly cool the storage chamber, and when the temperature in the storage chamber is lower than the temperature threshold, the control unit (50) executes soft landing control for driving the cooling device (20) to gently cool the storage chamber compared to the cooling control. Thus, a storage device capable of avoiding overcooling of stored articles and improving the cooling speed is provided.

Description

Storage device

Cross reference to related applications

This application is based on Japanese patent application 2015-216690, filed on 11/4/2015, the disclosure of which is incorporated by reference.

Technical Field

The present invention relates to a storage device having a cooling function.

Background

Conventionally, as such a storage device, there is a device described in patent document 1. The storage device described in patent document 1 includes: a receiving chamber for receiving food; a cooling device for cooling the storage chamber; an in-box thermistor for detecting the temperature in the storage chamber; and a control unit for controlling the operation of the cooling device so that the temperature in the storage chamber becomes a set temperature. The control unit operates the cooling device so that the temperature in the storage chamber becomes the residual heat removal temperature lower than the set temperature, and then operates the cooling device so that the temperature in the storage chamber becomes the set temperature.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 2015-81698

However, in the storage device described in patent document 1, since the manner of change in the temperature in the storage chamber differs depending on the type of food stored in the storage chamber, it is necessary to appropriately set the residual heat removal temperature. For example, if the residual heat removal temperature is set to a temperature lower than the appropriate temperature, the food may be excessively cooled, and thus the food may freeze. In addition, when the residual heat removal temperature is set to a temperature higher than the appropriate temperature, the time required to cool the food to the set temperature may be prolonged. Therefore, it is necessary to perform an operation of appropriately setting the residual heat removal temperature. This causes a reduction in the convenience of the storage device.

In addition, this case is not limited to a storage device for storing food, but is common to storage devices for storing food, vegetables, fruits, medicines, and the like in a cooled state.

Disclosure of Invention

The present invention has been made in view of such circumstances, and an object thereof is to provide a storage apparatus capable of avoiding overcooling of stored items and improving a cooling rate.

According to one aspect of the present invention, a storage device includes a storage room temperature detection unit and a control unit. The temperature detection unit in the storage chamber detects the temperature in the storage chamber. The control unit controls the driving of a cooling device that cools the storage chamber based on the set temperature. The control unit has a temperature threshold set to a temperature higher than the set temperature, and when the temperature in the storage chamber is equal to or higher than the temperature threshold, the control unit executes cooling control for driving the cooling device to rapidly cool the storage chamber, and when the temperature in the storage chamber is lower than the temperature threshold, the control unit executes soft landing control for driving the cooling device to gently cool the storage chamber compared to the cooling control, and calculates an estimated value of a temperature change speed in the storage chamber when the temperature in the storage chamber reaches the set temperature based on data of the temperature in the storage chamber detected by the storage chamber temperature detection unit until the temperature in the storage chamber reaches the temperature threshold, and when the temperature in the storage chamber reaches the temperature threshold, the control unit executes the soft landing control when the estimated value of the temperature change speed in the storage chamber is greater than the speed threshold value, and continues the cooling control when the estimated value of the temperature change speed in the storage chamber is equal to or less than the speed threshold value.

According to this configuration, since the cooling control is executed until the temperature in the storage chamber reaches the temperature threshold, the temperature in the storage chamber can be rapidly reduced to the temperature threshold. Therefore, the cooling rate can be increased. In addition, the soft landing control is executed after the temperature in the storage chamber reaches the temperature threshold value, so that the temperature in the storage chamber is gradually reduced to the set temperature, and thus overcooling of the stored objects in the storage chamber can be avoided.

According to the present invention, the cooling rate can be increased while avoiding overcooling of the stored material.

Drawings

Fig. 1 is a sectional view showing a schematic configuration of a storage device according to an embodiment of the present invention.

Fig. 2 is a block diagram schematically showing the configuration of a cooling device of the storage device according to the embodiment.

Fig. 3 is a block diagram showing an electrical configuration of the storage device according to the embodiment.

Fig. 4 is a flowchart showing a procedure of processing executed by the control unit of the storage apparatus according to the embodiment.

Fig. 5 is a graph showing changes in temperature in the storage chamber in the storage device according to the embodiment.

Fig. 6 is a graph showing changes in the temperature of the stored material in the storage device according to the embodiment.

Fig. 7 is a diagram for modeling the heat balance of the storage device according to the embodiment.

Fig. 8 is a graph showing a comparison between a change in temperature in the storage chamber in the storage device according to the embodiment and a change in temperature in the storage chamber in the storage device according to the comparative example.

Fig. 9 is a graph showing a comparison between a change in the core temperature of the stored material in the storage device according to the embodiment and a change in the core temperature of the stored material in the storage device according to the comparative example.

Detailed Description

Hereinafter, an embodiment of the storage device will be described. As shown in fig. 1, the storage device 1 of the present embodiment has a cooling function and is used to store a storage material 2 such as food, vegetable, fruit, and medicine in a cooled state. The storage device 1 includes a storage box body 10 and a cooling device 20.

The storage box body 10 is formed of a box-shaped member having heat insulation properties. A storage chamber 11 is formed inside the storage box body 10. An opening 11a is formed in one side surface of the storage chamber 11. The opening 11a is provided with a heat insulating door 12. The storage 2 can be stored in the storage chamber 11 by opening the heat insulating door 12. The heat-insulating door 12 is closed to seal the storage chamber 11, thereby storing the stored object 2 in a cooled state. Hereinafter, for convenience, the longitudinal direction of the housing chamber 11 is indicated by an arrow x. The width direction of the housing chamber 11 is indicated by an arrow y. The height direction of the housing chamber 11 is indicated by an arrow z.

A placement member 13 for placing the storage 2 is provided on the bottom surface portion 11b of the storage chamber 11. The mounting member 13 is formed of, for example, a plurality of T-shaped rails, and has a flat portion 13a and an upright portion 13 b. The flat portion 13a is a portion arranged parallel to the bottom surface portion 11b of the housing chamber 11. The storage 2 is placed on the upper surface of the flat portion 13 a. The standing portion 13b is a portion extending from the flat portion 13a to the bottom surface portion 11b of the storage compartment 11. The plurality of standing portions 13b are disposed at predetermined intervals in the storage chamber width direction y. An air passage 17 is formed by a space defined by the upright portions 13b, the flat portion 13a, and the bottom surface portion 11b of the housing chamber 11 adjacent to each other in the housing chamber width direction y. An air outlet 19 is formed at the end of the flat portion 13a on the side of the heat insulating door 12. The air passage 17 communicates with the housing chamber 11 via the air outlet 19.

The partition plate 15 is provided in the storage chamber 11 with a predetermined gap from the rear surface portion 11d of the storage chamber 11. The partition plate 15 is disposed to extend from the mounting member 13 in the housing chamber height direction z. The air passage 16 is formed by a space defined by the rear surface portion 11d of the housing chamber 11 and the partition plate 15. The air passage 16 communicates with the air passage 17. An air intake port 18 is formed between the upper end of the partition plate 15 and the upper surface 11c of the storage chamber 11. The housing chamber 11 and the air passage 16 communicate with each other through the air intake port 18.

The cooling device 20 cools the air in the storage chamber 11 by a refrigeration cycle. Specifically, as shown in fig. 2, the cooling device 20 includes an evaporator 21, a compressor 22, a condenser 23, and an expansion valve 24. These elements are connected in a ring shape by a pipe. The refrigerant circulates through each element via a pipe.

The compressor 22 sucks and compresses the refrigerant discharged from the evaporator 21, and discharges the compressed high-temperature refrigerant to the condenser 23. As shown in fig. 1, the condenser 23 is disposed outside the storage box body 10. The condenser 23 cools the compressed high-temperature refrigerant by exchanging heat between the refrigerant flowing inside and the air outside the storage box body 10. The expansion valve 24 decompresses the refrigerant cooled by flowing through the condenser 23. As shown in fig. 1, the evaporator 21 is disposed in the air passage 16. The evaporator 21 cools the air flowing through the air passage 16 by exchanging heat between the refrigerant flowing inside and the air flowing through the air passage 16.

As shown in fig. 1, the cooling device 20 includes a condenser fan 25 and a blower fan 26. The condenser fan 25 blows air outside the storage box body 10 to the condenser 23. The blower fan 26 blows air in the air passage 16 toward the evaporator 21. The air in the storage chamber 11 is circulated by blowing air by the blower fan 26 so as to: returns to the storage chamber 11 again through the air intake port 18, the air passage 16, the evaporator 21, the air passage 17, and the air discharge port 19. By such circulation of the air, the air cooled by the evaporator 21 is introduced into the storage chamber 11, and the air in the storage chamber 11 is cooled.

Next, an electrical structure of the storage device 1 will be described with reference to fig. 1 and 3. As shown in fig. 1, the storage device 1 includes an outside air temperature sensor 30, a storage compartment temperature sensor 31, a storage object temperature sensor 32, a discharge temperature sensor 33, and a return temperature sensor 34. The outside air temperature sensor 30 detects the outside air temperature To of the container body 10, and outputs a detection signal corresponding To the detected outside air temperature To. The storage chamber internal temperature sensor 31 detects the temperature Ti in the storage chamber 11, and outputs a detection signal corresponding to the detected temperature Ti in the storage chamber 11. In the present embodiment, the storage room temperature sensor 31 corresponds to a storage room temperature detection unit. The stored object temperature sensor 32 detects the surface temperature Tsk of the stored object 2, and outputs a detection signal corresponding to the detected surface temperature Tsk of the stored object 2. In the present embodiment, the stored object temperature sensor 32 corresponds to a stored object temperature detection unit. The outlet temperature sensor 33 detects the temperature of the air cooled by the cooling device 20, more specifically, the temperature of the air cooled by the evaporator 21, and outputs a detection signal corresponding to the detected evaporator outlet temperature Tco. In the present embodiment, the outlet air temperature sensor 33 corresponds to an outlet air temperature detection unit. The return temperature sensor 34 detects an evaporator intake temperature Tci, which is the temperature of the air taken in by the evaporator 21, and outputs a detection signal corresponding to the detected evaporator intake temperature Tci.

As shown in fig. 3, the storage device 1 includes an operation unit 40 and a control unit 50. The operation unit 40 is operated by a user. The user can set, for example, the temperature in the storage chamber 11 by operating the operation unit 40. Hereinafter, the temperature set by the operation of the operation unit 40 is referred to as "set temperature TA".

The Control Unit 50 is constituted by an ECU (Electronic Control Unit) mainly constituted by a microcomputer. The control unit 50 takes in detection signals of the sensors 30 to 34. The control unit 50 acquires the state quantities of the storage device 1 such as the outside air temperature To, the temperature Ti in the storage chamber 11, the surface temperature Tsk of the storage 2, the evaporator blowing temperature Tco, and the evaporator taking temperature Tci based on the detection signals of the sensors 30 To 34. The control unit 50 stores the acquired time series data of the various state quantities in the memory 51. Further, the control unit 50 takes in operation information of the operation unit 40. The control unit 50 acquires a set temperature TA in the storage chamber 11 set by a user, for example, based on the operation information of the operation unit 40. The control unit 50 controls the driving of the compressor 22, the condenser fan 25, and the blower fan 26 of the cooling device 20 based on the state quantity of the storage device 1 obtained from the detection signals of the sensors 30 to 34 and the operation information of the operation unit 40.

Next, the control of the cooling device 20 by the control unit 50 will be described in detail with reference to fig. 4. The control unit 50 repeatedly executes the processing shown in fig. 4 at a predetermined calculation cycle. The cooling flag F is set to the on state when the cooling device 20 is activated.

As shown in fig. 4, first, as the processing of step S1, the control unit 50 acquires various information such as the outside air temperature To, the temperature Ti in the storage chamber 11, the surface temperature Tsk of the storage 2, the evaporator blowing temperature Tco, and the evaporator taking-in temperature Tci based on the detection signals of the sensors 30 To 34. As the processing of step S2 following the processing of step S1, control unit 50 determines whether or not cooling is underway. Specifically, when the cooling flag F is on, the control unit 50 determines that cooling is underway.

When the cooling operation is being performed, an affirmative determination is made in step S2, and the controller 50 determines whether or not the temperature Ti in the storage chamber 11 is lower than the temperature threshold value Tth as the processing of the next step S3. The temperature threshold value Tth is set in advance to a temperature higher than the set temperature TA by a predetermined value. The predetermined value is set to, for example, "5 [ ° c ]. Since the inside of the housing chamber 11 is not cooled when the cooling device 20 is activated, the temperature Ti in the housing chamber 11 is often equal to or higher than the temperature threshold value Tth. When the temperature Ti in the storage chamber 11 is equal to or higher than the temperature threshold Tth, the control unit 50 makes a negative determination in the process of step S3 and executes the cooling control as the next process of step S4. The cooling control is control for driving the cooling device 20 to rapidly cool the inside of the storage chamber 11. As the cooling control, the control portion 50 drives the cooling device 20 to obtain, for example, a predetermined cooling performance. The predetermined cooling performance is, for example, the maximum cooling performance of the cooling device 20. Thus, the inside of the housing chamber 11 is rapidly cooled when the cooling device 20 is activated, and therefore, the cooling time required until the temperature Ti in the housing chamber 11 reaches the set temperature TA can be shortened. After executing the process of step S4, control unit 50 once ends the series of processes, and executes the process shown in fig. 4 again in the next calculation cycle.

When the temperature Ti in the housing chamber 11 is less than the temperature threshold value Tth during the execution of the cooling control, an affirmative determination is made in step S3, and the control unit 50 calculates an estimated value Δ τ of the cooling time required until the temperature Ti in the housing chamber 11 reaches the set temperature TA from the temperature threshold value Tth as the processing of the subsequent step S5. For example, as shown in fig. 5, when the temperature Ti in the storage chamber 11 reaches the temperature threshold Tth at the time τ 1, the control unit 50 analytically extrapolates data of the temperature Ti in the storage chamber 11, which is stored in the memory 51 during a period from the time τ 0 before the time τ 1 to the time τ 1, as shown by a two-dot chain line in the figure. The control unit 50 estimates a time τ 2 at which the temperature Ti in the housing chamber 11 reaches the set temperature TA based on the extrapolated data of the temperature Ti in the housing chamber 11, and calculates a cooling time Δ τ from the current time τ 1 to the time τ 2. The time Δ τ is an estimated value of the cooling time required from the current time τ 1 until the temperature in the storage chamber 11 reaches the set temperature TA.

As shown in fig. 4, as the processing of step S6 following the processing of step S5, the control unit 50 calculates an estimated value Tsk (τ 2) of the temperature of the stored item 2 at the time point when the temperature Ti in the storage chamber 11 reaches the temperature threshold Tth and an estimated value dTsk (τ 2)/d τ of the temperature change speed of the stored item 2. For example, as shown in fig. 6, the control unit 50 extrapolates data of the surface temperature Tsk of the container 2 by an analysis method as shown by a two-dot chain line in the figure, the data of the surface temperature Tsk of the container 2 being stored in the memory 51 during a period from the time τ 0 to the time τ 1. The control unit 50 calculates an estimated value Tsk (τ 2) of the temperature of the stored item 2 at a time τ 2 when the estimated value Δ τ of the cooling time has elapsed from the current time τ 1, based on the data of the surface temperature Tsk of the stored item 2 that is extrapolated. The control unit 50 calculates a differential value of the surface temperature Tsk of the storage 2 at the time τ 2 to obtain an estimated value dTsk (τ 2)/d τ of the temperature change rate of the storage 2.

As shown in fig. 4, as the processing of step S7 following the processing of step S6, the control unit 50 calculates an estimated value dTi (τ 2)/d τ of the temperature change rate in the storage chamber 11 at time τ 2 when the temperature Ti in the storage chamber 11 reaches the temperature threshold Tth, based on the estimated value Tsk (τ 2) of the temperature of the storage 2 and the estimated value dTsk (τ 2)/d τ of the temperature change rate of the storage 2. The estimated value dTi (τ 2)/d τ of the temperature change rate in the storage chamber 11 is calculated as follows.

Fig. 7 is a model showing the heat balance in the storage chamber 11. In the model shown in fig. 7, "Ga" indicates the air volume of the blower fan 26. "ε t" represents the heat exchange efficiency of the evaporator 21. "Tri" indicates the temperature of the refrigerant flowing into the evaporator 21. "Kbox" indicates the heat transfer rate of the housing chamber 11. "Fbox" indicates the heat transfer area of the housing chamber 11. "Kfv" indicates the heat transfer rate of the container 2. "Ffv" indicates the heat transfer area of the container 2. "Tcr" represents the core temperature, which is the temperature of the central portion of the container 2.

In the model shown in fig. 7, the following relational expression f1 holds. Note that, in the following expression f1, it is assumed that the temperature of the stored article 2 is the same, that is, the core temperature Tcr of the stored article 2 and the surface temperature Tsk of the stored article 2 are the same.

Ga·Cpa·εt·(Ti－Tri)·dτ

＝－Mfv·dTsk－Cpa·ρa·Va·dTi

+Kbox·Fbox·(To－Ti)·dτ

+Kfv·Ffv·(Tsk－Ti)·dτ···(f1)

In formula f1, "Cpa" represents the constant pressure specific heat of air. "Mfv" indicates the heat capacity of the container 2. "ρ a" represents the air density. "Va" represents the volume of the storage chamber 11, in other words, the volume of air in the storage chamber 11.

The left side of the equation f1 represents the heat quantity when the heat exchange rate ∈ t is used in the evaporator 21 to exchange heat between the air in the storage chamber 11 and the refrigerant, the air in the storage chamber 11 having a temperature Ti, and the refrigerant flowing into the evaporator 21 having a temperature Tri. The first term on the right side of the equation f1 represents the amount of heat divided by the temperature change of the container 2. The second term on the right side of the equation f1 represents the amount of heat divided by the temperature change in the storage chamber 11. The third term on the right side of the equation f1 represents the amount of heat that enters from the outside through the outer wall of the storage box body 10 per unit time d τ. The fourth term of the expression f1 represents the amount of heat released from the storage 2 into the storage chamber 11 per unit time d τ.

By modifying the expression f1, the following expression f2 can be obtained as a relational expression of the heat budget at the time τ 2.

dTi(τ2)/dτ＝1/(Cpa·ρa·Va)

·{－Mfv·(dTsk(τ2)/dτ)

+Kbox·Fbox·(To(τ2)－Ti(τ2))

+Kfv·Ffv·(Tsk(τ2)－Ti(τ2))

－Ga·Cpa·εt·(Ti(τ2)－Tri(τ2))}···(f2)

The control unit 50 calculates the estimated value dTi (τ 2)/d τ of the temperature change rate in the storage chamber 11 using the equation f 2. Specifically, assuming that the outside air temperature To (τ 2) at the time τ 2 is the same as the current outside air temperature To (τ 1), the control unit 50 uses the current outside air temperature To (τ 1) detected by the outside air temperature sensor 30 as the outside air temperature To (τ 2). Further, since the temperature Ti (τ 2) in the housing chamber 11 at the estimated time τ 2 reaches the set temperature TA, the control portion 50 uses the set temperature TA as the temperature Ti (τ 2) in the housing chamber 11. Further, when the cooling control is executed, the cooling device 20 is driven with the predetermined cooling performance, and therefore the temperature Tri of the refrigerant flowing into the evaporator 21 becomes the temperature of the refrigerant when the cooling device 20 is operated with the predetermined cooling performance. In the present embodiment, the temperature of the refrigerant during the cooling control is measured in advance by an experiment or the like. The control unit 50 uses the temperature of the refrigerant measured in advance as the temperature Tri (τ 2) of the refrigerant at the time τ 2. For the other parameters, constants previously stored in the memory 51 are used.

As a result, the control unit 50 can calculate the estimated value dTi (τ 2)/d τ of the temperature change rate in the storage chamber 11 by substituting the estimated value Tsk (τ 2) of the temperature of the storage 2 and the estimated value dTsk (τ 2)/d τ of the temperature change rate of the storage 2 obtained in the process of step S7 shown in fig. 4 into equation f 2.

As the processing of step S8 following the processing of step S7, the control unit 50 determines whether the estimated value dTi (τ 2)/d τ of the temperature change speed in the storage chamber 11 is larger than the speed threshold α, and the speed threshold α is a negative value, and the speed threshold α is set in advance by an experiment or the like so as to determine whether or not the temperature in the storage chamber 11 can be converged to the set temperature TA. even when the cooling control is continuously performed, and the speed threshold α may be set based on the state quantity of the storage apparatus 1 acquired by the detection signals of the sensors 30 to 34.

However, the following control method is considered: the cooling control is executed until the temperature Ti in the housing chamber 11 reaches the set temperature TA, and the control shifts to the normal control at a point in time when the temperature Ti in the housing chamber 11 reaches the set temperature TA. The general control is as follows: the compressor 22 of the cooling device 20 is driven by feedback control such as PID control based on a deviation between the evaporator blowing temperature Tco and the set temperature TA. Since the cooling control is a control for rapidly cooling the inside of the storage chamber 11, it may be difficult to cool the center portion of the storage 2 depending on the type of the storage. When the center portion of the storage 2 is not sufficiently cooled at the time point when the cooling control is shifted to the normal control, the temperature Ti of the storage chamber 11 may deviate from the set temperature TA due to heat radiated from the storage 2 to the storage chamber 11.

On the other hand, when the central portion of the storage 2 is not sufficiently cooled, the temperature change speed dTi/d τ in the storage chamber 11 is reduced by the heat re-radiation of the storage 2, and therefore, by determining whether the estimated value dTi (τ 2)/d τ of the temperature change speed in the storage chamber 11 is larger than the speed threshold value α, it is possible to determine whether the heat re-radiation of the storage 2 is easily performed at the time point when the temperature Ti in the storage chamber 11 reaches the set temperature TA.

Therefore, when the estimated value dTi (τ 2)/d τ of the temperature change speed in the storage chamber 11 is greater than the speed threshold value α, the control unit 50 of the present embodiment makes an affirmative determination in the determination processing of step S8, in this case, the control unit 50 determines that the re-heat dissipation of the storage object 2 is likely to occur, and executes the soft landing control as the processing of step S9, the soft landing control is control of driving the cooling device 20 so as to more gently cool the storage chamber 11 than the cooling control, specifically, the soft landing control is control of driving the compressor 22 of the cooling device 20 or the like by feedback control based on the deviation of the temperature Ti in the storage chamber 11 from the set temperature TA, specifically, PID control, and the control unit 50 executes the soft landing control until the temperature Ti in the storage chamber 11 reaches the set temperature TA, and thus, the temperature Ti in the storage chamber 11 approaches the set temperature TA while the storage object 2 is gradually cooled, and as a result, the temperature Tcr in the storage chamber 11 is difficult to shift from the set temperature TA in the storage chamber 11 to the normal temperature control.

As the processing of step S10 following the processing of step S9, control unit 50 sets cooling flag F to the off state, and then ends the series of processing. In this case, when the process shown in fig. 4 is executed by the control unit 50 in the next calculation cycle, the control unit 50 makes a negative determination in the determination process of step S2, and executes the normal control as the process of the next step S12.

On the other hand, when the estimated value dTi (τ 2)/d τ of the temperature change speed in the storage chamber 11 is equal to or less than the speed threshold value α, the control unit 50 makes a negative determination in the determination process of step S8, in this case, the control unit 50 determines that the re-heat radiation of the storage object 2 is hard to occur, and continues the cooling control until the temperature Ti in the storage chamber 11 reaches the set temperature TA as the process of step S11, whereby the time required until the temperature Ti in the storage chamber 11 reaches the set temperature TA can be shortened, and further, since the re-heat radiation of the storage object 2 is hard to occur, even when the time point at which the temperature Ti in the storage chamber 11 reaches the set temperature TA is shifted from the cooling control to the normal control, the temperature Ti in the storage chamber 11 is hard to deviate from the set temperature TA., and therefore the temperature Ti in the storage chamber 11 can be controlled to the set temperature TA.

As the processing of step S10 following the processing of step S11, control unit 50 sets cooling flag F to the off state, and then ends the series of processing. In this case, when the control unit 50 executes the processing shown in fig. 4 in the next calculation cycle, the control unit 50 makes a negative determination in the determination processing of step S2, and executes the normal control as the processing of the next step S12.

Next, the operation of the storage device 1 of the present embodiment will be described.

In fig. 8, a solid line indicates a change in temperature Ti in the housing chamber 11 in the housing apparatus 1 of the present embodiment, and a two-dot chain line indicates a change in temperature Ti in the housing chamber 11 in the housing apparatus of the comparative example. In the storage device of the comparative example, the cooling control is executed until the set temperature TA is reached, and the control shifts to the normal control at the time point when the set temperature TA is reached. In the storage apparatus of the comparative example, during execution of the normal control, the cooling control is executed again when the temperature Ti in the storage chamber 11 exceeds the temperature threshold value Tth.

As shown by the two-dot chain line in fig. 8, the storage apparatus of the comparative example executes the cooling control until the time τ 11 at which the temperature Ti in the storage chamber 11 reaches the set temperature TA. In this case, when the center portion of the storage 2 is not cooled at the time τ 11, the temperature Ti in the storage chamber 11 rises due to the heat emitted from the storage 2. When the temperature Ti in the storage chamber 11 exceeds the temperature threshold value Tth at time τ 12, the cooling control is executed again. Thereafter, in the storage apparatus of the comparative example, the temperature Ti in the storage chamber 11 converges to the set temperature TA while the cooling control and the normal control are repeatedly performed.

On the other hand, as shown by the solid line in fig. 8, in the housing apparatus 1 of the present embodiment, since the soft landing control is executed at the time point when the temperature Ti in the housing chamber 11 reaches the temperature threshold value Tth at the time τ 10, the temperature Ti in the housing chamber 11 gradually converges to the set temperature TA after the time τ 10. This can avoid a situation in which the cooling control and the normal control are repeatedly executed as in the storage device of the comparative example, and thus can reduce the power loss of the compressor 22. Further, it is possible to suppress the cooling time from increasing due to the switching of the control.

In fig. 9, a solid line indicates a change in the core temperature of the storage 2 in the storage device 1 of the present embodiment, and a two-dot chain line indicates a change in the core temperature of the storage in the storage device of the comparative example. As shown in fig. 9, the storage device 1 of the present embodiment can shorten the time until the core temperature of the storage 2 converges on the set temperature TA by the predetermined time Δ τ 10, as compared with the storage device of the comparative example.

According to the storage device 1 of the present embodiment described above, the following operations and effects (1) to (6) can be obtained.

(1) When the temperature Ti in the storage chamber 11 is equal to or higher than the temperature threshold value Tth, the control unit 50 executes cooling control. This can rapidly reduce the temperature Ti in the storage chamber 11 to the temperature threshold value Tth, and thus can increase the cooling rate. When the temperature Ti in the storage chamber 11 is less than the temperature threshold value Tth, the control unit 50 executes the soft landing control. This can gradually lower the temperature Ti in the storage chamber 11 to the set temperature TA, thereby avoiding overcooling of the stored item 2.

(2) The control unit 50 calculates an estimated value dTi (τ 2)/d τ of the temperature change speed in the storage chamber 11 when the temperature Ti in the storage chamber 11 reaches the set temperature TA based on data of the temperature Ti in the storage chamber 11, which is detected by the storage chamber temperature sensor 31 until the temperature Ti in the storage chamber 11 reaches the temperature threshold Tth, when the temperature Ti in the storage chamber 11 reaches the temperature threshold Tth, the control unit 50 performs the soft landing control if the estimated value dTi (τ 2)/d τ of the temperature change speed in the storage chamber 11 is greater than the speed threshold α, and the control unit 50 continues the cooling control if the estimated value dTi (τ 2)/d τ of the temperature change speed in the storage chamber 11 is equal to or less than the speed threshold α, thereby enabling the cooling time to be continuously controlled in a state where the temperature Ti in the storage chamber 11 converges to the set temperature TA even if the soft landing control is not performed, and therefore enabling the cooling time to be shortened.

(3) The control unit 50 calculates the estimated value Δ τ of the cooling time based on data of the temperature Ti in the storage chamber 11 detected by the storage chamber temperature sensor 31 until the temperature Ti in the storage chamber 11 reaches the temperature threshold value Tth. The control unit 50 calculates an estimated value Tsk (τ 2) of the temperature of the stored item 2 at a time point when the temperature Ti in the storage chamber 11 reaches the set temperature TA and an estimated value dTsk (τ 2)/d τ of the temperature change speed of the stored item 2 based on data of the temperature Ti in the storage chamber 11 detected by the storage chamber temperature sensor 31 until the temperature Ti in the storage chamber 11 reaches the temperature threshold value Tth and the estimated value Δ τ of the cooling time. The control unit 50 calculates an estimated value dTi (τ 2)/d τ of the temperature change rate in the storage chamber 11 based on the estimated value Tsk (τ 2) of the temperature of the storage 2 and the estimated value dTsk (τ 2)/d τ of the temperature change rate of the storage 2. This makes it possible to accurately calculate the estimated value dTi (τ 2)/d τ of the temperature change rate in the storage chamber 11, and as a result, it is possible to accurately determine whether or not to execute the soft landing control.

(4) As the soft landing control, the control unit 50 executes feedback control based on a deviation between the temperature Ti in the storage chamber 11 and the set temperature TA. This allows the temperature Ti in the housing chamber 11 to gradually converge to the set temperature TA.

(5) As the cooling control, the control portion 50 drives the cooling device 20 to obtain a predetermined cooling performance. This makes it possible to rapidly cool the inside of the storage chamber 11.

(6) The control unit 50 executes, as normal control, feedback control based on a deviation between the evaporator blowing temperature Tco and the set temperature TA when the temperature Ti in the housing chamber 11 reaches the set temperature TA by execution of the soft landing control. This makes it possible to easily maintain the temperature Ti in the storage chamber 11 at the set temperature TA.

The above embodiment can also be implemented as follows.

The method of execution of the normal control can be appropriately changed. For example, the control unit 50 may execute feedback control based on a deviation between the temperature Ti in the storage chamber 11 and the set temperature TA as normal control. In short, the normal control may be control for controlling the driving of the cooling device 20 based on the set temperature TA.

The method of performing the cooling control can be appropriately changed. For example, as the cooling control, the control unit 50 may change a feedback gain such as a PID gain so that the cooling capacity of the cooling device 20 is improved as compared with the normal control. In short, the cooling control may be control for driving the cooling device 20 to rapidly cool the inside of the storage chamber 11.

The method of implementing the soft landing control can be appropriately changed. For example, as the soft landing control, the control unit 50 may execute feedback control based on comparison between the evaporator blowing temperature Tco and the set temperature TA. In short, the soft landing control may be control for driving the cooling device 20 so as to cool the inside of the storage chamber 11 more gently than the cooling control.

The control unit 50 may calculate a differential value of the temperature Ti in the storage chamber 11 at the time τ 2 based on the extrapolated data of the temperature Ti in the storage chamber 11, and obtain an estimated value dTi (τ 2)/d τ of the temperature change rate in the storage chamber 11. This makes it possible to easily calculate the estimated value dTi (τ 2)/d τ of the temperature change rate in the storage chamber 11, and therefore, the calculation load of the control unit 50 can be reduced.

The control unit 50 may always execute the soft landing control when the temperature Ti in the storage chamber 11 is lower than the temperature threshold value Tth. That is, in the processing shown in fig. 4, the case dividing processing of step S8 may be omitted.

The method of detecting the temperature Ti in the storage chamber 11 is not limited to the method of directly detecting the temperature Ti by the storage chamber temperature sensor 31, and may be a method of calculating the temperature Ti from the evaporator outlet temperature Tco and the evaporator inlet temperature Tci by using, for example, a map.

As parameters such as the heat transfer rates Kbox, Kfv, the heat transfer areas Fbox, Ffv in the equation f2, the control unit 50 may use, for example, input values from the operation unit 40, instead of using information stored in advance in the memory 51. Thus, the user can easily customize various parameters of the format f2, and convenience can be improved.

The model showing the heat budget shown in fig. 7 can be modified as appropriate. For example, a model may be used in which the intake heat generated by the leakage air in the storage chamber 11, the heat generation amount of the motor of the blower fan 26, and the like are further added. Further, the calculation formula of the estimated value dTi (τ 2)/d τ of the temperature change rate in the storage chamber 11 may be appropriately changed according to the model used.

Until the temperature Ti of the storage chamber 11 reaches the temperature threshold Tth, the control unit 50 may calculate the estimated value Δ τ of the cooling time, the estimated value Tsk (τ 2) of the temperature of the storage 2, the estimated value dTsk (τ 2)/d τ of the temperature change rate of the storage 2, and the estimated value dTi (τ 2)/d τ of the temperature change rate in the storage chamber 11. Specifically, for example, the control unit 50 calculates each estimated value based on data of the temperature Ti in the storage chamber 11 detected by the storage chamber temperature sensor 31 before the temperature in the storage chamber 11 reaches the temperature threshold value Tth.

The functions provided by the control unit 50 can be provided by software stored in a physical storage device, a computer that executes the software, software alone, hardware alone, or a combination of these. For example, in the case where the control unit 50 is provided by an electronic circuit as hardware, the function provided by the control unit 50 can be provided by a digital circuit including a plurality of logic circuits or an analog circuit.

The present invention is not limited to the specific examples described above. That is, those skilled in the art add appropriate design changes to the above specific examples, and the present invention is also included in the scope of the present invention as long as the characteristics of the present invention are provided. For example, the elements, their arrangement, conditions, and the like included in the above-described specific examples are not limited to the examples and can be appropriately modified. The elements of the above-described embodiments can be combined as long as they are technically possible, and the combination of these elements is also included in the scope of the present invention as long as it includes the features of the present invention.

The present invention has been described in terms of embodiments, but it should be understood that the present invention is not limited to the embodiments and configurations. The present invention also includes various modifications and modifications within a range equivalent thereto. Further, various combinations and modes and further including only one of these elements, and other combinations and modes above and below are also within the scope and idea of the present invention.

Claims

1. A storage device is characterized by comprising:

a storage chamber temperature detection unit (31) that detects the temperature inside the storage chamber (11); and

a control unit (50) that controls the driving of a cooling device (20) that cools the storage chamber on the basis of a set temperature,

the control portion has a temperature threshold set to a temperature higher than the set temperature,

the control unit executes cooling control for driving the cooling device to rapidly cool the storage chamber when the temperature in the storage chamber is equal to or higher than the temperature threshold value,

the control portion executes a soft landing control, which is a control of driving the cooling device to gently cool the inside of the housing compared to the cooling control, in a case where the temperature inside the housing is lower than the temperature threshold value, and,

the control unit calculates an estimated value of a temperature change speed in the storage chamber when the temperature in the storage chamber reaches the set temperature, based on data of the temperature in the storage chamber detected by the storage chamber temperature detection unit until the temperature in the storage chamber reaches the temperature threshold,

the control unit executes the soft landing control when an estimated value of a temperature change speed in the storage chamber is greater than a speed threshold when the temperature in the storage chamber reaches the temperature threshold,

the control unit continues the cooling control when an estimated value of a temperature change speed in the storage chamber is equal to or less than a speed threshold.

2. The storage device of claim 1,

further comprises a storage temperature detecting part (32) for detecting the temperature of the storage in the storage chamber,

the control unit calculates an estimated value of cooling time required until the temperature in the storage chamber reaches the set temperature, based on data of the temperature in the storage chamber detected by the storage chamber temperature detection unit until the temperature in the storage chamber reaches the temperature threshold, and,

the control unit calculates an estimated value of the temperature of the stored object and an estimated value of a temperature change speed of the stored object at a time point when the temperature in the storage chamber reaches the set temperature, based on data of the temperature of the stored object detected by the stored object temperature detection unit until the temperature in the storage chamber reaches the temperature threshold value,

the control unit calculates an estimated value of a temperature change rate in the storage chamber based on an estimated value of the temperature of the storage object and an estimated value of a temperature change rate of the storage object.

3. The storage device of claim 1 or 2,

the control unit executes, as the soft landing control, feedback control based on a deviation between the temperature in the storage chamber and the set temperature.

4. The storage device of claim 1 or 2,

as the cooling control, the control portion drives the cooling device to obtain a predetermined cooling performance.

5. The storage device of claim 1 or 2,

further comprises a blow-out temperature detection unit (33) for detecting the temperature of the air cooled by the cooling device,

the control unit executes feedback control based on a deviation between the temperature of the air blown out from the cooling device and the set temperature when the temperature in the storage chamber reaches the set temperature by executing the cooling control or the soft landing control.