JP6840038B2 - Evaluation method of temperature fluctuation of cooling storage, and cooling storage - Google Patents

Description

The present invention relates to a cold storage for storing an object at a desired temperature and a method for evaluating temperature fluctuations in the cold storage. The cold storage according to the present invention is particularly suitable for application to a chemical storage for storing a drug in a cold storage at an optimum temperature.

In the field of cooling storage, it is known that the temperature inside the storage can be maintained at a set temperature. For example, in Patent Document 1, as the operation of the chemical storage, the control device controls the operation of the compressor and the blower of the cooling device based on the output of the temperature sensor, and circulates the cold air in the storage room. It is described that the temperature is maintained at the optimum temperature of the chemical at ± 1 ° C. (Patent Document 1, paragraph number 0032). In Patent Document 2, the compressor and the condenser fan are energized so that the microcomputer maintains the freezer chamber at the set temperature (for example, -10 ± 2 ° C.) set in the operation panel based on the signal from the thermistor. It is described that the cooling operation is performed under control (paragraph number 0017 of Patent Document 2).

Japanese Unexamined Patent Publication No. 2008-11904 Japanese Unexamined Patent Publication No. 2000-234785

As in Patent Documents 1 and 2, when a target temperature is set by a user in a conventional cooling storage, a target temperature zone consisting of a predetermined temperature range centered on the target temperature is set, and the target temperature zone is within the target temperature range. The temperature inside the refrigerator is maintained. However, the "inside temperature" in the conventional cooling storage including Patent Documents 1 and 2 means the average temperature value of the inside temperature detected by the temperature sensor, and the "inside temperature" is the target temperature range. The fact that it is included in the inside means that the average temperature value of the temperature inside the refrigerator is included in the target temperature range. Therefore, even if the maximum or minimum temperature inside the refrigerator actually detected by the temperature sensor greatly exceeds the target temperature range, it is determined that the average temperature value is included in the target temperature range. It may be done. As described above, it cannot be said that the temperature expression based on the conventional average temperature value "inside temperature" accurately captures the temperature inside the inside.

The present invention has been made to solve the above-mentioned problems of the conventional cooling storage, and the cooling storage can accurately grasp the temperature condition not only in one place in the storage but also in the entire storage. An object of the present invention is to obtain a method for evaluating temperature fluctuations and a cooling storage in which the temperature fluctuations detected by the evaluation method are small and the temperature inside the refrigerator can be maintained uniformly.

The present invention includes a storage main body 1 having an internal R for storing a storage object, a door 2 that is openably attached to the storage main body 1 and closes a front opening leading to the internal R, and an internal R storage. A circulation fan 5 that circulates the internal air, a cooling device 3 that cools the internal air, a temperature sensor 6 that detects the internal temperature D, and a temperature setting unit 26 that receives the input of the target temperature D0 of the internal R. The target temperature zone is set based on the target temperature D0 input by the temperature setting unit 26, and the operating state of the cooling device 3 and the circulation fan 5 is controlled so that the internal temperature D is maintained within the target temperature zone. The subject is a method for evaluating temperature fluctuations in a cold storage provided with a control device 25. Measurement points are set at a plurality of locations in the refrigerator R, and the temperature inside the refrigerator is measured at each measurement point for a total of 1 hour from 1 hour to 2 hours after the door 2 is closed, and the measurement temperature at the measurement point is measured. The DM is characterized in that the degree of temperature fluctuation of the internal R is captured by detecting whether or not the following temperature conditions are satisfied.
<Temperature condition>
(I) (D0)-(Allowable fluctuation temperature) ≤ (DM _AVE ) ≤ (D0) + (Allowable fluctuation temperature)
(Ii) (DM _MAX )-(DM _MIN ) ≤ (allowable fluctuation temperature) x 2
(Iii) (DM _ALLMAX )-(DM _ALLMIN ) ≤ (allowable fluctuation temperature) x 2

(D0): Target temperature (DM _AVE ): Average value of measurement temperature (DM) at _{each measurement point (DM MAX} ): Maximum temperature at each measurement point (DM _MIN ): Minimum temperature at each measurement point (DM _ALLMAX ): Maximum temperature at all measurement points (DM _ALLMIN ): Minimum temperature at all measurement points

The "variable allowable temperature" in claim 1 is a temperature range that defines a target temperature zone set around the target temperature. For example, the target temperature is 3 ° C. and the target temperature zone is 3 ° C. ± 1 ° C. When set, the permissible fluctuation temperature is 1 ° C.

Specifically, by detecting whether or not the following temperature conditions (iv) are satisfied in addition to the above temperature conditions (i) to (iii), the degree of temperature fluctuation of the internal R can be determined. It can be captured.
(Iv) (D0) + (Allowable fluctuation temperature) <(DM _ALLMAX ) <(D0) + (Allowable fluctuation temperature) x 2

Specifically, at least three measuring plates, upper, middle, and lower, are installed in the internal R, and measurement points are installed at four corners of each measuring plate and at a total of five points in the center of the board. By setting measurement points at least 15 points in the refrigerator R and detecting whether or not the above temperature conditions are satisfied based on the measurement temperatures at at least 15 measurement points in the refrigerator R. It is possible to take a form that captures the degree of temperature fluctuation of the internal R.

The present invention includes a storage main body 1 having an internal R for storing a storage object, a door 2 that is openably attached to the storage main body 1 and closes a front opening leading to the internal R, and an internal R storage. A circulation fan 5 that circulates the internal air, a cooling device 3 that cools the internal air, a temperature sensor 6 that detects the internal temperature D, and a temperature setting unit 26 that receives the input of the target temperature D0 of the internal R. The target temperature zone is set based on the target temperature D0 input by the temperature setting unit 26, and the operating state of the cooling device 3 and the circulation fan 5 is controlled so that the internal temperature D is maintained within the target temperature zone. The target is a cold storage provided with a control device 25. Then, the measured temperature DM at the measurement point by the above evaluation method is characterized in that it satisfies all the following temperature conditions (i) to (iv).
<Temperature condition>
(I) (D0) -1 ° C ≤ (DM _AVE ) ≤ (D0) + 1 ° C
(Ii) (DM _MAX )-(DM _MIN ) ≤ 2 ° C
(Iii) (DM _ALLMAX )-(DM _ALLMIN ) ≤ 2 ° C
(Iv) (D0) + 1 ° C <(DM _ALLMAX ) <(D0) + 2 ° C

(D0): Target temperature (DM _AVE ): Average value of measurement temperature (DM) at _{each measurement point (DM MAX} ): Maximum temperature at each measurement point (DM _MIN ): Minimum temperature at each measurement point (DM _ALLMAX ): Maximum temperature at all measurement points (DM _ALLMIN ): Minimum temperature at all measurement points

The cooling storage has at least two modes: a high-precision operation mode in which the target temperature zone is set within the target temperature ± 1 ° C, and an eco mode in which the target temperature zone is set within the target temperature ± 2 ° C. The control device 25 controls the operating states of the cooling device 3, the heating heater 4, and the circulation fan 5 according to the selection of these modes. Then, in the high-precision operation mode, the operation mode in the normal state where the temperature inside the refrigerator is within the target temperature range is defined as the normal operation mode, and in the high-precision mode, the operation when the temperature inside the refrigerator falls into an abnormal state outside the target temperature range. When the mode is defined as the return mode, it can be assumed that the temperature of the refrigerator R in the normal operation mode satisfies all of the temperature conditions (i) to (iv).

In the evaluation method according to the present invention, measurement points are provided not only at one location of the refrigerator R but also at a plurality of locations of the refrigerator R, and the temperature fluctuation of the refrigerator R is based on the measurement temperature DM at these measurement points. Because it is designed to capture the temperature status of the actual machine, it is possible to check the temperature status of the actual machine more accurately. _{Then, as in condition (i), by checking whether the average value (DM AVE} ) of the measured temperature DM at each measurement point is within the target temperature range (D0 ± allowable fluctuation temperature), at each measurement point. It can be confirmed that the average temperature is within the target temperature range. _{By checking whether the fluctuation range ((DM MAX} )-(DM MIN)) at each measurement point is within the temperature range twice the allowable fluctuation temperature as in condition (ii), each measurement point It can be confirmed that the temperature change in the above is substantially uniform and there is no significant difference. _{By checking whether the} fluctuation range ((DM ALLMAX)-(DM _ALLMIN )) at all measurement points is within the temperature range twice the allowable fluctuation temperature as in condition (iii), some of them It can be confirmed that the maximum temperature at the measurement points is not remarkably high and the minimum temperature at some measurement points is not remarkably low, and the temperature fluctuation in the refrigerator is substantially constant. From the above, according to the evaluation method according to the present invention, by setting the measurement points in the entire chamber, it is possible to accurately grasp the temperature condition in the entire chamber. Further, by using the evaluation method according to the present invention, by setting the measurement points in the entire chamber, the temperature distribution in the entire chamber and the fluctuation range of the temperature in the entire chamber can be accurately grasped and evaluated. can do. Based on the above, the present invention is useful for evaluating temperature fluctuations in a cooling storage where there is no variation in temperature changes in the entire chamber and more stable temperature control in the entire chamber is required, and in particular, strict stability in the entire chamber is required. It is useful for evaluation of chemical storage where sex is required.

_{When the temperature rises by allowing the maximum temperature (DM ALLMAX} ) at all measurement points to exceed the limit temperature ((D0) + (allowable fluctuation temperature)) of the target temperature range as in condition (iv). It is possible to improve the practical convenience of the cooling storage by recognizing a slight overshoot of.

At least three measuring plates, upper, middle, and lower, are installed in the internal R, and measurement points are installed at four corners of each measuring plate and a total of five points in the center of the board. The temperature inside the refrigerator is detected by installing measurement points at at least 15 points in total and detecting whether or not the above temperature conditions are satisfied based on the measurement temperatures at at least 15 measurement points in the refrigerator R. It is possible to take a form that captures the degree of fluctuation. By installing the measurement points in the entire chamber in this way, it is possible to accurately grasp the temperature condition in the entire chamber.

In the present invention, the measurement temperature DM at the measurement point by the evaluation method as described above is
(I) (D0) -1 ° C ≤ (DM _AVE ) ≤ (D0) + 1 ° C
(Ii) (DM _MAX )-(DM _MIN ) ≤ 2 ° C
(Iii) (DM _ALLMAX )-(DM _ALLMIN ) ≤ 2 ° C
(Iv) (D0) + 1 ° C <(DM _ALLMAX ) <(D0) + 2 ° C
It can be a cooling storage that satisfies all the temperature conditions of.
According to the cooling storage according to the present invention, there is no significant change in the temperature change at a plurality of locations of the internal R, and the entire internal R can be maintained at a stable and uniform temperature. Therefore, it is possible to obtain a cooling storage capable of controlling the internal temperature with higher accuracy. The cooled storage according to the present invention can be expected to be particularly applied to a chemical storage.

It is a time chart which shows the operation in the normal control mode of the high precision operation mode of the cooling storage which concerns on this invention. It is a figure which shows the structure of the cooling storage. It is a refrigerant circuit diagram of a cooling storage. It is a block diagram of a cooling storage. It is a time chart which shows the operation in the 1st return mode of a high precision operation mode. It is a time chart which shows the operation in the 2nd return mode of a high precision operation mode. It is a time chart which shows the operation in the 1st defrost mode. It is a time chart which shows the operation in the 2nd defrosting mode. It is a time chart which shows the operation in the eco-mode of the cooling storage which concerns on this invention. (A) shows the evaluation method of the temperature fluctuation in the normal control mode of the high precision operation mode, is a figure which shows the maximum temperature, the minimum temperature, and the average temperature at each measurement point, and (b) is the figure in the refrigerator. It is a figure explaining the measurement point. It is a flowchart which shows the operation in a high precision operation mode. It is a flowchart which shows the operation in a high precision operation mode.

(Examples) FIGS. 1 to 12 show a method for evaluating temperature fluctuations in a cooled storage according to the present invention, and an example in which the cooled storage is applied to a chemical storage. The front / rear, left / right, and up / down in the present invention follow the crossing arrows shown in FIG. As shown in FIG. 2, the drug storage swings open / close the storage main body (storage main body) 1 having a storage space for storing and storing the drug to be stored, and the opening / closing opening on the front surface of the storage main body 1. Door 2, a cooling device 3 that supplies cold air to the storage space R of the storage body 1, a heating heater 4 that heats the air in the storage R, a circulation fan 5 that circulates the air in the storage, and the like. It has. A machine room 8 is provided under the storage main body 1, and a compressor 9 constituting a cooling device 3, a condenser 10, a condenser fan 11 and the like are arranged therein.

The storage main body 1 is configured as a heat insulating box, and a heat exchange chamber 12 is partitioned in the upper part of the chamber R, and a cold air duct 13 is partitioned along the rear surface wall. The circulation fan 5 and the evaporator 14 constituting the cooling device 3 are arranged near the rear of the heat exchange chamber 12, and the heater 4 is arranged on the rear surface of the evaporator 14. Further, a temperature sensor 6 for detecting the temperature D in the refrigerator is provided adjacent to the front surface of the evaporator 14 in the ceiling wall of the heat exchange chamber 12, and the defrost sensor 15 is provided in the evaporator 14. The internal R is provided with a multi-stage shelf 16 for storing and storing medicines such as reagents, blood products, and vaccines for each group. The internal air supplied by the circulation fan 5 is cooled while passing through the evaporator 14 and flows to the cold air duct 13, and from the cold air outlets opened at a plurality of places above and below the duct 13 to the internal R. Will be sent. In FIG. 2, reference numeral 17 is an open / close sensor for detecting the opening / closing of the door 2, and reference numeral 18 is a control box arranged in the upper part of the front surface of the storage body 1. The rotation speed of the circulation fan 5 can be changed in three stages: low speed (first rotation speed), medium speed (second rotation speed), and high speed.

As shown in FIG. 3, in the cooling device 3, the compressor 9, the condenser 10, the dryer 21, the expander 22, and the evaporator 14 driven by a motor are connected in a loop by a refrigerant pipe 24. It is composed of. A control device 25 is housed inside the control box 18 in order to control the operating states of the compressor 9, the heater 4, and the circulation fan 5 to maintain the internal temperature D in the target temperature range. In FIG. 3, reference numeral 26 is a target temperature setting unit (temperature setting unit) for inputting a target internal temperature (hereinafter referred to as a target temperature D0) to the control device 25, and is provided on the front surface of the control box 18. The target temperature D0 can be set to, for example, 3 ° C., 4 ° C., 5 ° C., or the like, depending on the type of the drug stored in the chamber R.

As shown in FIG. 4, a start / stop protection timer 30 is connected to the control device 25. Further, the memory connected to the control device 25 stores a correction value table 31 in which a temperature correction value determined by the outside air temperature and the target temperature D0 in the refrigerator is stored. The start / stop protection timer 30 has an on-protection time T1 (3 minutes in this embodiment) that can be stopped after the compressor 9 is started, or an off-protection time that can be started after the compressor 9 is stopped. It is timed that T2 (5 minutes in this embodiment) has passed. The control device 25 has a target temperature D0 input in advance, an internal temperature D detected by the temperature sensor 6, a time measurement result of the start / stop protection timer 30, and a temperature according to the outside air temperature read from the correction value table 31. The operating state of each device is controlled based on the correction value. This chemical storage has two control modes, a high-precision operation mode and an eco-mode. In the high-precision operation mode, the internal temperature D is set to a target temperature of ± 1 ° C centered on the target temperature D0. Maintain within the band range (eg, D0 ± 1 ° C.). In the eco mode, the temperature inside the refrigerator D is maintained within a target temperature range of ± 2 ° C. centered on the target temperature D0 (for example, D0 ± 2 ° C.). In the eco mode, power consumption can be suppressed as compared with the high precision operation mode.

In the following description, the normal operation mode of the high-precision operation mode is defined as the normal control mode, and the operation mode when an abnormal state occurs in the high-precision operation mode is defined as the return mode. That is, when the high-precision operation mode is selected, the control device 25 normally controls the temperature in the normal control mode, which is the main operation mode, and exceptionally, the internal temperature D is the upper limit of the target temperature range. If the temperature exceeds the temperature and becomes abnormally high, follow the first return mode, and if the rate of decrease of the internal temperature D is abnormally fast, follow the second return mode. By controlling the operating state of the above, the temperature D inside the refrigerator is returned to a state where it can be controlled in the normal control mode, and the temperature is shifted to the normal control mode.

(Normal control mode)
The normal control mode in the high-precision operation mode will be described with reference to the time chart of FIG. 1 and the flowchart of FIG. As shown in FIG. 1, the compressor 9 and the heater 4 are in the off state, the circulation fan 5 is rotating at a low speed, and the internal temperature D, which tends to rise, is equal to or lower than the on temperature Dn1 of the compressor 9. When the state is set to the initial state (t0), the control device 25 performs the primary temperature control to the fourth temperature control as described in detail below to maintain the internal temperature D in the target temperature zone. Here, the target temperature D0 is 3 ° C., and the target temperature zone is set in the range of ± 1 ° C. centered on the target temperature D0, that is, 2 ° C. to 4 ° C. (3 ° C. ± 1 ° C.).

First, in the initial state (t0), since the circulation fan 5 is only rotated at a low speed and the compressor 9 is in the off state, the cooling operation by the evaporator 14 is not performed, and the internal temperature D is the time. It gradually rises with the passage of time (start in FIG. 11). Then, in a state where the time measured by the start / stop protection timer 30 has passed the “off protection time T2” which is the shortest off time of the compressor 9 (“YES” in S1 of FIG. 11), the time tends to increase. Primary temperature control at the time when a certain internal temperature D rises above the target temperature D0 (3 ° C.) and reaches the compressor on temperature Dn1 (3.3 ° C.) (t1, “=” in S2 of FIG. 11). Is done. Specifically, when the temperature D inside the refrigerator, which is on the rise, rises above the target temperature D0 (3 ° C.) and reaches the compressor on temperature Dn1 (3.3 ° C.) (t1), the control device 25 The compressor 9 is started while the circulation fan 5 is rotating at a low speed, and the heater 4 is operated at the same time (S3 in FIG. 11). In this way, if the compressor 9 is operated when the temperature inside the refrigerator D rises by 0.3 ° C. from the target temperature D0 to lower the temperature D inside the refrigerator, which has tended to rise until then, compression is performed. It is possible to moderate the temperature change in the vicinity of the machine-on temperature Dn1 and reliably prevent the internal temperature D from falling into an overshoot state. Further, since the compressor 9 and the heating heater 4 are operated in the state where the circulation fan 5 is rotated at a low speed, the internal temperature D is set higher than that in the case where only the compressor 9 is started without operating the heating heater 4. It can be gradually lowered to slow down the temperature drop when the on-protection time T1 elapses, and to prevent overcooling. As a result, the time from the start of the compressor 9 to the next stop of the compressor 9 can be made sufficiently longer than the on-protection time T1 to prevent the compressor 9 from operating frequently. Further, since not only the compressor 9 but also the heating heater 4 is operated at the same time while the circulation fan 5 is rotated at a low speed, it is possible to suppress the supply of a large amount of cold air to the chamber R in a short time. .. Therefore, it is possible to suppress the occurrence of variation in the internal temperature D and contribute to the uniformity of the internal temperature D.

When the heating time T3 elapses after the start of the operation of the heater 4 in the state of performing the primary temperature control (t2, YES in S4 of FIG. 11), the control device 25 stops the operation of the heater 4. Then (S5 in FIG. 11), the secondary temperature is controlled. The heating time T3 can be derived from the correction value stored in the correction value table 31, and differs according to the change in the outside air temperature. The time T3 when the outside air temperature is low is the time when the outside air temperature is high. It is set to be longer than T3. In the secondary temperature control as described above, since the operation of the heater 4 is stopped, the degree of decrease in the internal temperature D is larger than the degree of decrease in the internal temperature D before the secondary temperature control is performed. ..

When the start / stop protection timer 30 clocks that the "on protection time T1", which is the minimum on-time that can be stopped after the compressor 9 is started, has elapsed in the state where the secondary temperature is controlled ( When t3, “YES” in S6 of FIG. 11) and the internal temperature D exceeds the target temperature D0 (“YES” in S7 of FIG. 11), the control device 25 rotates the circulation fan 5 at a low speed. The tertiary temperature is controlled to switch from to medium speed rotation (t3, S8 in FIG. 11). By increasing the rotation speed of the circulation fan 5 from the low speed rotation to the medium speed rotation in this way, the amount of heat exchange in the evaporator 14 increases, so that the decrease in the internal temperature D can be promoted. Further, since the amount of heat exchange in the evaporator 14 is increased, the temperature D in the refrigerator can be quickly lowered to the target temperature D0, and the degree of circulation of the cold air in the refrigerator can be increased to make the temperature in the refrigerator uniform. Further, in the tertiary temperature control, after the internal temperature D drops to the target temperature D0 (“YES” in S9 in FIG. 11), the circulation fan 5 is rotated at a low speed (t4, S10 in FIG. 11). In this way, by rotating the circulation fan 5 at a low speed, the amount of heat exchange in the evaporator 14 can be reduced. Therefore, the degree of decrease in the internal temperature D is made moderate, and in the vicinity of the compressor off temperature Df1. The temperature change can be moderated.

After the tertiary temperature control, when the temperature inside the refrigerator D, which tends to decrease, drops to the compressor off temperature Df1 (2.7 ° C.) (t5, “YES” in S11 of FIG. 11), the control device 25 uses the compressor 9 4th temperature control is performed to turn the temperature D inside the refrigerator upward (S12 in FIG. 11). In this way, by stopping the compressor 9 as soon as the temperature inside the refrigerator D drops by 0.3 ° C. from the target temperature D0, the downward tendency of the temperature inside the refrigerator D can be weakened, so that the compressor off temperature can be weakened. By slowing the temperature change in the vicinity of Df1, it is possible to reliably prevent the internal temperature D from falling into an undershoot state.

After performing the 4th temperature control, the initial state is returned and the primary temperature control is performed again. Since the temperature inside the refrigerator after the fourth temperature control only rises by the amount of cold heat lost through the cold storage main body 1 and the door 2, the temperature inside the refrigerator is compared with the case where the temperature inside the refrigerator is forcibly lowered by the freezing device 3. Therefore, the temperature rise tendency becomes extremely slow and slow (t5 to t6). Therefore, regardless of the extremely high outside air temperature, in many cases where the outside air temperature is in the normal temperature range, the time measured by the start / stop protection timer 30 is before the off protection time T2 of the compressor 9 elapses. There is little possibility that the internal temperature D will rise to the compressor on temperature Dn1. Therefore, the time from when the compressor 9 is stopped until when the compressor 9 is started next can be made sufficiently longer than the off protection time T2 to prevent the compressor 9 from operating frequently. However, if the time measured by the start / stop protection timer 30 does not elapse the off protection time T2 of the compressor 9 (“NO” in S1 of FIG. 11), the compressor 9 is not operated.

As described above, in the normal control mode in the high-precision operation mode, especially in the primary temperature control, the compressor 9 and the heating heater 4 are operated in a state where the circulation fan 5 is rotated at a low speed (t1). In S3) of FIG. 11, as compared with the case where only the compressor 9 is started without operating the heater 4, the temperature inside the refrigerator D is gradually lowered to reduce the temperature when the on-protection time T1 elapses. It can be slowed down to prevent overcooling. Further, since the temperature can be lowered slowly, the time from the start of the compressor 9 to the next stop of the compressor 9 is made sufficiently longer than the on-protection time T1, and the compressor 9 operates frequently. Can be prevented. Further, since not only the compressor 9 but also the heating heater 4 is operated at the same time while the circulation fan 5 is rotating at a low speed (t1), a large amount of cold air is supplied to the chamber R at a time. However, it is possible to make the temperature D inside the refrigerator uniform by suppressing the variation in the temperature D inside the refrigerator.

(1st return mode)
The first return mode in the high-precision operation mode will be described with reference to the time chart of FIG. 5 and the flowcharts of FIGS. 11 and 12. For example, when the door 2 is opened to take in and take out medicines when the outside air temperature is higher than the inside temperature D (t0), the outside air enters the inside R, so that the off protection time T2 of the compressor 9 is set. Even though the temperature has not passed, the internal temperature D may greatly exceed the upper limit temperature (D0 + 1 ° C.) of the target temperature range (t1). Further, even when the opening time of the door 2 is prolonged, the internal temperature D may greatly exceed the upper limit temperature (D0 + 1 ° C.) of the target temperature zone. When such a situation occurs, the control device 25 controls the operating states of the compressor 9, the heating heater 4, and the circulation fan 5 in the first return mode, and promptly sets the internal temperature D to the target temperature range (D0 ± 1 ° C.). ). In such a first return mode, the target temperature is D0 + γ (in this embodiment, the temperature (2 ° C.) is twice the temperature width (+ 1 ° C.) on the high temperature side of the target temperature zone centered on the target temperature D0). Based on the upper limit threshold temperature, the control device 25 controls the operating state of the compressor 9, the heater 4, and the circulation fan 5. That is, in this embodiment, the upper limit threshold temperature is set to a temperature 2 ° C. higher than the target temperature D0.

In the first return mode, the control device 25 has the off protection time T2 measured by the start / stop protection timer 30 in a state where the door 2 is closed and the open / close sensor 17 is switched to the on state (t0). Waiting for the elapse (“YES” in S1 of FIG. 11), and if the internal temperature D exceeds the compressor on temperature Dn1 at that time (“>” in S2 of FIG. 11), the control device 25 Operates the compressor 9 and the heater 4 while the circulation fan 5 is rotating at a low speed (t1, S13 in FIG. 11), and the upper limit of the internal temperature D at this time is 2 ° C. higher than the target temperature D0. When the threshold temperature is exceeded (“>” in S14 of FIG. 11), the fifth-order temperature control is performed. When the internal temperature D is equal to or lower than the upper limit threshold temperature (“≦” in S14 of FIG. 11), the fifth-order temperature control is not performed and the normal control mode is entered (S4 of FIG. 11).

In the fifth-order temperature control, the control device 25 compresses while stopping the heater 4 (S15 in FIG. 12) until the internal temperature D drops to the upper threshold temperature (t2, “YES” in S16 in FIG. 12). Operate the machine 9. In such fifth-order temperature control, if the temperature inside the refrigerator D drops to the upper limit threshold temperature by the elapse of the compressor on protection time T1 (“NO” in S21 of FIG. 12) (t2, in S16 of FIG. 12). “YES”), the heater 4 is operated (S17 in FIG. 12), and the sixth temperature control for gradually lowering the internal temperature D is performed.

In the sixth temperature control, when the operating time of the heater 4 reaches the heating time T3 (“YES” in S18 in FIG. 12), the heater 4 is stopped (t3, S19 in FIG. 12). When the start / stop protection timer 30 clocks that the on-protection time T1 has elapsed after the sixth-order temperature control is performed (t4, “YES” in S20 of FIG. 12), the third-order of the previous normal control mode After shifting to temperature control, the circulation fan 5 is rotated at a medium speed to lower the internal temperature D (S8 in FIG. 11), and when the internal temperature drops to the target temperature D0 (t5), the circulation fan 5 is slowed down. Rotate it to reduce the rate of decrease in the temperature D inside the refrigerator. Even when the compressor-on protection time T1 has elapsed before the internal temperature D drops to the upper limit threshold temperature (“NO” in S16 of FIG. 12) (“YES” in S21 of FIG. 12), Shifts to the tertiary temperature control of the normal control mode (S8 in FIG. 11). Even when the on-protection time T1 of the compressor 9 elapses before the energization time T3 of the heating heater 4 elapses (“NO” in S18 of FIG. 12) (“YES” in S22 of FIG. 12), the heating heater 4 is stopped (S23 in FIG. 12), and the process shifts to the tertiary temperature control in the normal control mode (S8 in FIG. 11). Since the heating heater 4 in the sixth temperature control starts operating after the internal temperature D drops to the upper limit threshold temperature, the time until the heating heater 4 stops operating and the circulation fan 5 is rotated at a medium speed ( t3 to t4) are shorter than in the normal control mode.

As described above, in the fifth-order temperature control, since only the compressor 9 is activated, the internal temperature D exceeding the upper limit threshold temperature (D0 + 2 ° C.) is rapidly lowered to the upper limit threshold temperature (D0 + 2 ° C.). be able to. Further, in the sixth temperature control, when the temperature inside the refrigerator D drops to the upper limit threshold temperature (D0 + 2 ° C.), the heating heater 4 is operated for the heating time T3 to gradually lower the temperature D inside the refrigerator, so that the temperature is turned on. It is possible to moderate the temperature drop when the protection time T1 elapses and prevent overcooling. Further, since the time from the start of the compressor 9 to the stop of the compressor 9 can be made sufficiently longer than the on-protection time T1, it is possible to prevent the compressor 9 from operating frequently. At the final stage of the 6th temperature control, the process shifts to the 3rd temperature control, the circulation fan 5 is rotated at a medium speed to lower the internal temperature D, and when the internal temperature D drops to the target temperature D0, The circulation fan 5 can be rotated at a low speed to moderate the rate of decrease in the internal temperature D, and the tendency of the internal temperature D to decrease can be weakened. Therefore, the temperature change in the vicinity of the compressor off temperature Df1 can be moderated, and the internal temperature D can be reliably prevented from falling into the undershoot state. After the third-order temperature control is completed, the normal control mode shifts to the fourth-order temperature control.

(Second return mode)
The second return mode in the high-precision operation mode will be described with reference to the time chart of FIG. 6 and the flowchart of FIG. When the door 2 is opened to take in and take out medicines when the outside air temperature is lower than the inside temperature D, the outside air enters the inside R, so that the compressor 9 timed by the start / stop protection timer 30 is turned on. Even though the protection time T1 has not elapsed, the temperature D in the refrigerator may become lower than the target temperature D0. In such a situation, the control device 25 controls the operating states of the compressor 9, the heater 4, and the circulation fan 5 in the following second return mode, so that the temperature D in the refrigerator drops rapidly. To prevent.

In the second return mode, when the door 2 is closed and the open / close sensor 17 is switched to the on state (t0), the temperature inside the refrigerator D tends to decrease, so that the on protection time T1 of the compressor 9 elapses. The temperature inside the refrigerator D may drop to the target temperature D0 before the operation. In that case, even if the on-protection time T1 of the compressor 9 has elapsed (t1, “YES” in S6 of FIG. 11 and “NO” in S7), the circulation fan 5 is still kept in a low-speed rotation state. 7th temperature control is performed. Further, in the 7th temperature control, when the internal temperature D reaches the compressor off temperature Df1 (t2), the operation of the compressor 9 is stopped to shift the internal temperature D to an increase, which is 4 in the normal control mode. Move to the next temperature control.

As described above, in the 7th temperature control, since the internal temperature D has dropped to the target temperature D0 before the on-protection time T1 of the compressor 9 has elapsed, the circulation fan 5 is maintained in the low-speed rotation state. Therefore, the amount of heat exchange in the evaporator 14 is reduced. As a result, the degree of subsequent decrease in the internal temperature D can be made gradual. Further, in the 7th temperature control, when the internal temperature D, which tends to decrease, drops to the compressor off temperature Df1 (2.7 ° C.), the compressor 9 is stopped early, so that the internal temperature D of the internal temperature D is increased. It is possible to weaken the downward tendency and moderate the temperature change in the vicinity of the compressor off temperature Df1. Therefore, even in the second return mode, it is possible to reliably prevent the internal temperature D from falling into the undershoot state.

In addition, in the normal control mode of the high-precision operation mode, the first defrosting mode as described in detail below is performed at regular intervals (3 hours) based on the detection temperature of the defrosting sensor 15, and the door is further subjected to. Every time 2 is opened, a second defrosting mode is performed to remove frost adhering to the refrigerant pipe and fin group of the evaporator 14. FIG. 7 shows a time chart of the first defrost mode, and FIG. 8 shows a time chart of the second defrost mode.

(1st defrost mode)
In the first defrosting mode, after 3 hours set in the normal control mode have elapsed, the temperature inside the refrigerator, which tends to decrease, drops to the compressor off temperature Df1 (2.7 ° C.), and the operation of the compressor 9 is stopped. It is started immediately after it is done (t0). Specifically, the control device 25 rotates the circulation fan 5 at a third rotation speed (high-speed rotation) higher than the second rotation speed at the same time as the compressor 9 is stopped, and the amount of heat exchange in the evaporator 14 Is increased to remove frost and ice adhering to the fin group of the evaporator 14 and the refrigerant pipe. At this time, if the circulation fan 5 is continuously rotated at high speed until the defrosting is completed, the internal temperature D rises before the off protection time T2 of the compressor 9 elapses, and the upper limit temperature (D0 + 1 ° C.) of the target temperature zone rises. ) May be exceeded. Therefore, the control device 25 intermittently rotates the circulation fan 5 at high speed every time the compressor 9 is stopped, and sets the operation stop condition of the circulation fan 5 to the set temperature R0 (1.5 ° C.) of the defrost sensor 15. Set as follows according to the relationship between the actual detection temperature and the temperature inside the refrigerator during defrosting.

When the circulation fan 5 is rotated at high speed for the first time (t0), the detection temperature C1 of the defrost sensor 15 satisfies the following condition formula 1, and when that state is maintained for 3 seconds, the circulation fan 5 is slowed down. Rotate. Alternatively, the circulation fan 5 is rotated at a low speed when the actual internal temperature D satisfies the following conditional expression 2 with respect to the target temperature D0 (3 ° C.) in the internal chamber and the state is maintained for 3 seconds.
(R0: set temperature, C1: detection temperature of defrost sensor 15, target temperature D0)
Conditional expression 1 ... ((R0-0.5 ° C.) <C1)
Conditional expression 2 ... ((D0 + 1.5 ° C.) <Actual internal temperature D)
In FIG. 7, when the circulation fan 5 is rotated at high speed for the first time, the circulation fan 5 is slowed down when the detection temperature C1 of the defrost sensor 15 rises from the lowest temperature (R0-0.5 ° C.). It is rotating (t1). After rotating the circulation fan 5 at a low speed, the primary temperature control in the normal control mode described above is performed to the fourth temperature control to prevent the internal temperature D from exceeding the upper limit temperature of the target temperature zone. Waiting for the compressor 9 to stop, the circulation fan 5 is rotated at high speed again.

When the circulation fan 5 is rotated at high speed for the second time (t2), the detection temperature C1 of the defrost sensor 15 satisfies the following condition formula 3, and when that state is maintained for 3 seconds, the circulation fan 5 is slowed down. Rotate (t3). Alternatively, the circulation fan 5 is rotated at a low speed when the actual internal temperature D satisfies the above-mentioned conditional expression 2 with respect to the target temperature D0 (3 ° C.) in the internal chamber and the state is maintained for 3 seconds.
Conditional expression 3 ... (R0 <C1)
In FIG. 7, when the circulation fan 5 is rotated at high speed for the second time, the circulation fan 5 circulates when the detection temperature C1 of the defrost sensor 15, which tends to rise, reaches the set temperature R0 (1.5 ° C.) (t3). The fan 5 is rotating at a low speed.

When the circulation fan 5 is rotated at high speed for the third or fourth time (t4, t6), the detection temperature C1 of the defrost sensor 15 satisfies the following conditional expression 4, and the state is maintained for 3 seconds. The circulation fan 5 is rotated at a low speed (t5, t7). Alternatively, the circulation fan 5 is rotated at a low speed when the actual internal temperature D satisfies the above-mentioned conditional expression 2 with respect to the target temperature D0 (3 ° C.) in the internal chamber and the state is maintained for 3 seconds.
Conditional expression 4 ... ((R0 + 0.5) <C1)
In FIG. 7, when the circulation fan 5 is rotated at high speed for the third and fourth times, the circulation fan 5 reaches the time when the detection temperature C1 of the defrost sensor 15, which tends to rise, reaches 2 ° C. (t5, t7). Is rotating at low speed.

As described above, when the circulation fan 5 is intermittently rotated at high speed each time the compressor 9 is stopped, and the detection temperature C1 of the defrosting sensor 15 when the operation of the circulation fan 5 is stopped is gradually increased, the refrigerator is stored. The defrosting of the evaporator 14 can be reliably performed while preventing the internal temperature D from rising beyond the upper limit of the target temperature zone. Incidentally, in the conventional medical cold storage, every time the compressor is stopped, the defrosting operation is performed and then the cooling operation is performed. Further, even if the defrosting operation is performed every time the compressor is stopped, if the defrosting is not sufficiently performed, the defrosting operation is performed at regular intervals to shift to the cooling operation. However, such an operation control method has a problem in that it is unavoidable that the temperature inside the refrigerator rises beyond the upper limit of the target temperature range during the defrosting operation, and the drug is likely to be deteriorated or deteriorated.

(2nd defrost mode)
The second defrosting mode will be described with reference to FIG. When the door 2 is opened and closed for taking in and out medicines and the like, the moisture contained in the external air that has entered the chamber R is frosted on the evaporator 14 and the heat exchange efficiency is lowered. In order to solve such a problem, in the second defrosting mode, the defrosting operation is performed every time the door 2 is opened to remove the frost adhering to the refrigerant pipe and the fin group of the evaporator 14. Specifically, when the door 2 is opened (t0) and the internal temperature D rises beyond the upper limit temperature of the target temperature zone, the door 2 is closed and the open / close sensor 17 is turned on in the normal control mode. When the off protection time T2 of the compressor 9 elapses, the compressor 9 is started (t1). When it is timed by the start / stop protection timer 30 that the on-protection time T1 that can be stopped has elapsed since the compressor 9 is started, the control device 25 rotates the circulation fan 5 at a medium speed to set the temperature inside the refrigerator D. The decrease is promoted (t2), and when the internal temperature D decreases to the target temperature D0, the circulation fan 5 is rotated at a low speed to alleviate the decrease rate of the internal temperature D (the tertiary temperature of the previous normal control mode). control). When the internal temperature D drops to the compressor off temperature Df1 (2.7 ° C.) (t3), the compressor 9 is stopped and the mode shifts to the second defrosting mode. If the internal temperature D when the compressor 9 is started is less than 5 ° C., the circulation fan 5 is accelerated from low speed rotation to medium speed rotation at the same time as the compressor 9 is started, and the internal temperature is increased. When the temperature in the refrigerator D drops to the compressor off temperature Df1 (2.7 ° C.) (t3), the compressor 9 is stopped and the mode shifts to the second defrosting mode.

In the second defrosting mode, the circulation fan 5 is rotated at high speed (t3) at the same time as the compressor 9 is stopped, and the amount of heat exchange in the evaporator 14 is increased to form the fins of the evaporator 14 and the refrigerant pipe. Remove attached frost and ice. The operation stop condition of the circulation fan 5 is set as follows according to the relationship between the set temperature R0 (1.5 ° C.) of the defrost sensor 15 and the actual detection temperature.

When the circulation fan 5 is rotated at high speed for the first time (t3), the detection temperature C1 of the defrost sensor 15 satisfies the following conditional expression 5, and when that state is maintained for 3 seconds, the circulation fan 5 is slowed down. Rotate (t4). Alternatively, if the detection temperature C1 of the defrost sensor 15 does not rise even though 20 minutes have passed since the circulation fan 5 started high-speed rotation, for example, ((R0 + 1 ° C.)> = C1). When the circulation fan 5 is rotated at a low speed (t4).
Conditional expression 5 ... ((R0 + 1 ° C.) <C1)

In the second defrosting mode, the circulation fan 5 is accelerated from medium speed rotation to high speed rotation (t3) to increase the amount of heat exchange in the evaporator 14 to perform defrosting. As the defrosting progresses by rotating the circulation fan 5 at high speed, the detection temperature C1 of the defrosting sensor 15 rises, but when the detection temperature C1 rises to (set temperature R0 + 1 ° C = 2.5 ° C). The circulation fan 5 is rotated at a low speed (t4). In this way, the circulation fan 5 is switched from high-speed rotation to low-speed rotation before the off-protection time T2 elapses from the stop of the compressor 9, and when the off-protection time T2 elapses, the compressor 9 is turned on again. At the same time, the heater 4 is activated to reduce the temperature inside the refrigerator. The temperature D inside the refrigerator when the compressor 9 is started after the off protection time T2 has elapsed from the stop of the compressor 9, is slightly higher than the compressor on temperature Dn1, and the compressor 9 is on-protected. When the time T1 elapses, the circulation fan 5 is accelerated from low-speed rotation to medium-speed rotation to promote a decrease in the internal temperature D (t5).

When the internal temperature D drops to the target temperature D0 (3 ° C.) (t6), the circulation fan 5 is rotated at a low speed to moderate the subsequent temperature drop. The compressor 9 is stopped (t7) in a state where the internal temperature D has dropped to the compressor off temperature Df1 (2.7 ° C.), and at the same time, the circulation fan 5 is rotated at high speed to increase the amount of heat exchange in the evaporator 14. Then, the frost and ice adhering to the fins of the evaporator 14 and the refrigerant pipe are removed again. When the circulation fan 5 is rotated at high speed for the second time (t7), when the detection temperature C1 of the defrost sensor 15 satisfies the conditional expression 3 (R0 <C1) described above and the state is maintained for 3 seconds. The circulation fan 5 is rotated at a low speed (t8). Alternatively, if the detection temperature C1 of the defrost sensor 15 does not rise even though 20 minutes have passed since the circulation fan 5 started high-speed rotation, for example, ((R0 + 1 ° C.)> = C1). When the circulation fan 5 is rotated at a low speed (t8).

In FIG. 8, when the circulation fan 5 is rotated at high speed for the second time (t7), the circulation fan 5 circulates when the detection temperature C1 of the defrosting sensor 15, which tends to rise, reaches the set temperature R0 (1.5 ° C.). The fan 5 is rotating at a low speed (t8). As described above, in the second defrosting mode, at the same time as the compressor 9 is stopped, the circulation fan 5 is intermittently rotated at high speed in two steps. Further, when the detection temperature C1 of the defrost sensor 15 rises to (set temperature R0 + 1 ° C = 2.5 ° C) and when the detection temperature C1 reaches the set temperature R0 (1.5 ° C), the circulation fan 5 is operated. Rotate at a low speed to prevent the temperature D inside the refrigerator from rising sharply. Therefore, it is possible to reliably defrost the evaporator 14 each time the door 2 is opened, while preventing the temperature D inside the refrigerator from rising beyond the upper limit of the target temperature zone.

(Eco-mode)
The eco mode will be described with reference to the time chart of FIG. As shown in FIG. 9, the initial state is a state in which the compressor 9 is in the off state, the circulation fan 5 is rotating at a low speed, and the temperature inside the refrigerator, which tends to rise, is equal to or lower than the on temperature Dn2 of the compressor 9. At (t0), the control device 25 performs the following control to maintain the internal temperature D in the target temperature zone. Here, the target temperature D0 is 3 ° C., and the target temperature zone is set in the range of ± 2 ° C. centered on the target temperature D0, that is, 1 ° C. to 5 ° C. (3 ° C. ± 2 ° C.).

First, in the initial state (t0), since the circulation fan 5 is only rotated at a low speed and the compressor 9 is in the off state, the cooling operation by the evaporator 14 is not performed, and the internal temperature D is the time. It rises gently over time. Then, when the temperature D in the refrigerator, which tends to rise, rises above the target temperature D0 (3 ° C.) and reaches the compressor on temperature Dn2 (3.7 ° C.) (t1), the control device 25 uses the compressor 9 Is started to start the cooling operation by the evaporator 14, and the temperature D in the refrigerator is lowered. When the start / stop protection timer 30 measures the elapse of the on-protection time T1 that can be stopped after the compressor 9 is started (t2), the control device 25 changes the rotation speed of the circulation fan 5 from low speed to medium. Switch to fast rotation.

By increasing the rotation speed of the circulation fan 5 from low-speed rotation to medium-speed rotation, the amount of heat exchange in the evaporator 14 increases, so that the decrease in the internal temperature D can be promoted. In addition to being able to quickly lower the internal temperature D to the target temperature D0, the degree of circulation of cold air in the internal R can be increased to make the internal temperature D uniform. When the internal temperature D, which tends to decrease, decreases to the compressor off temperature Df2 (2.3 ° C.) (t3), the control device 25 stops the operation of the compressor 9 and reduces the rotation speed of the circulation fan 5. The temperature inside the refrigerator D is turned upward by lowering the rotation from the high speed to the low speed. In this way, when the internal temperature D drops to the compressor off temperature Df2 (2.3 ° C.) (t3), the operation of the compressor 9 is stopped, and at the same time, the rotation speed of the circulation fan 5 is changed from medium speed to low speed. When the temperature is lowered to, the temperature D in the refrigerator can be gently raised, so that the time until the temperature D in the refrigerator reaches the compressor on temperature Dn2 and the compressor 9 is started is sufficiently longer than the off protection time T2. can do. After that, by controlling the operating states of the compressor 9 and the circulation fan 5 in the same procedure as described above, the internal temperature D can be maintained in the target temperature range.

FIG. 10 shows an evaluation method of a temperature change in the refrigerator in the normal control mode of the high-precision operation mode. This evaluation method is for confirming the variation of the internal temperature D in the entire internal R in the high-precision operation mode and the uniformness of the internal temperature D, as shown in FIG. 10 (b). , Temperature sensors are installed at each of the four corners and the center of each shelf 16 installed in the upper and lower three stages of the internal R of the chemical storage, and are detected by each temperature sensor when operating in the normal control mode. It captures the change in the measured temperature DM of the internal R.

Here, the measurement points related to the four corners of the upper shelf 16 are designated as A to D, and the measurement points related to the central portion of the shelf 16 are designated as E. Similarly, the measurement points related to the middle shelf 16 are F to J, and the measurement points related to the lower shelf 16 are KO. The outside air conditions were an air temperature of 30 ° C. and a humidity of 60%. The set temperature (target temperature D0) was set to 3 ° C, the permissible fluctuation temperature was set to 1 ° C, and the target temperature range was set to 2 ° C to 4 ° C. The measurement time was 1 hour from 1 hour after the door 2 was closed to 2 hours after the door 2 was closed.

_{As shown in FIG. 10A, looking at the average temperature (DM AVE} ) at each measurement point (A to O), the minimum average temperature is 3.3 ° C. (measurement point J), and the maximum average temperature. Was 3.8 ° C. (measurement points A, D, E). Therefore, in the high-precision operation mode of the chemical storage according to this embodiment, the average temperature (DM _AVE ) at all the measurement points of the internal R is kept within the range of ± 1.0 ° C. with respect to the target temperature D0. It was confirmed that the temperature distribution in the refrigerator can be kept uniform without variation not only in the horizontal direction but also in the vertical direction. That is, it was confirmed that the temperature condition (i) in the present invention was satisfied.

In addition, the temperature fluctuation range ((DM _MAX )-(DM _MIN )) at each measurement point (A to O) was 1.8 ° C. (measurement point F) at the maximum (1.0 ° C. (minimum)). Measurement point E)). From this, in the high-precision operation mode of the chemical storage according to the present embodiment, the temperature fluctuation range at each measurement point of the internal R can be kept within 2 ° C. It was confirmed that it was prepared. That is, it was confirmed that the temperature condition (ii) in the present invention was satisfied.

Furthermore, the maximum temperature (DM _ALLMAX ) at all measurement points is 4.4 ° C (measurement points A, B, C, D, N), and the minimum temperature (DM _ALLMIN ) is 2.5 ° C (measurement points F, J). ), The fluctuation range ((DM _ALLMAX )-(DM _ALLMIN )) at all measurement points was 1.9 ° C (4.4 ° C-2.5 ° C). Therefore, in the high-precision operation mode of the chemical storage according to the present embodiment, not only the temperature fluctuation range at each measurement point of the internal R but also the temperature fluctuation range at all the measurement points of the internal R is kept within 2 ° C. It was confirmed that the inside of the refrigerator had excellent temperature stability. That is, it was confirmed that the temperature condition (iii) in the present invention was satisfied.

Further, the maximum temperature (DM _ALLMAX ) at all the measurement points was 4.4 ° C., and it was confirmed that the temperature condition (iv) in the present invention was satisfied. As described above, the chemical storage in the present embodiment satisfies all of the temperature conditions (i) to (iv) in the evaluation method of the present invention, and the temperature change does not vary in the entire storage and is more stable. It was confirmed that the temperature control of the entire chamber can be performed.

In the above embodiment, an example in which the cooling storage is applied to the chemical storage is shown, but the present invention is not limited to this. The target temperature and the target temperature zone are not limited to those shown in the above examples.

1 Storage body (storage body)
2 Door 3 Cooling device 5 Circulation fan 6 Temperature sensor 25 Control device 26 Temperature setting unit R Inside

Claims (5)

A storage body (1) having a storage body (R) for storing a storage object, and a door (2) that is openably attached to the storage body (1) and closes the front opening leading to the storage body (R). , A circulation fan (5) that circulates the inside air of the inside (R), a cooling device (3) that cools the inside air, a temperature sensor (6) that detects the inside temperature (D), and a refrigerator. The target temperature zone is set based on the temperature setting unit (26) that accepts the input of the target temperature (D0) in (R) and the target temperature (D0) input by the temperature setting unit (26), and the temperature inside the refrigerator. This is a method for evaluating temperature fluctuations in a cooling storage equipped with a cooling device (3) and a control device (25) for controlling the operating state of the circulation fan (5) so that (D) is maintained within the target temperature range. hand,
Measurement points are set at multiple points in the refrigerator (R), and the temperature inside the refrigerator is detected at each measurement point for a total of 1 hour from 1 hour to 2 hours after the door (2) is closed, and the measurement is performed. A method for evaluating temperature fluctuations in a cooling storage, which comprises detecting the degree of temperature fluctuations in the refrigerator (R) by detecting whether or not the following temperature conditions are satisfied for the measured temperature (DM) at a point.
<Temperature condition>
(I) (D0)-(Allowable fluctuation temperature) ≤ (DM _AVE ) ≤ (D0) + (Allowable fluctuation temperature)
(Ii) (DM _MAX )-(DM _MIN ) ≤ (allowable fluctuation temperature) x 2
(Iii) (DM _ALLMAX )-(DM _ALLMIN ) ≤ (allowable fluctuation temperature) x 2

(D0): Target temperature (DM _AVE ): Average value of measurement temperature (DM) at _{each measurement point (DM MAX} ): Maximum temperature at each measurement point (DM _MIN ): Minimum temperature at each measurement point (DM _ALLMAX ): Maximum temperature at all measurement points (DM _ALLMIN ): Minimum temperature at all measurement points Claim to capture the degree of temperature fluctuation in the refrigerator (R) by detecting whether or not the following temperature conditions (iv) are satisfied in addition to the above temperature conditions (i) to (iii). The method for evaluating temperature fluctuations in the cooling storage according to 1.
(Iv) (D0) + (Allowable fluctuation temperature) <(DM _ALLMAX ) <(D0) + (Allowable fluctuation temperature) x 2 At least three measuring plates, upper, middle, and lower, are installed in the refrigerator (R).
Measurement points were set at four corners of each measuring plate and at least five points in the center of the board, and at least 15 measurement points were set in the refrigerator (R).
Claim 1 that captures the degree of temperature fluctuation in the refrigerator (R) by detecting whether or not the above temperature conditions are satisfied based on the measured temperatures at at least 15 measurement points in the refrigerator (R). Alternatively, the method for evaluating temperature fluctuations in the cooling storage according to 2. A storage body (1) having a storage body (R) for storing a storage object, and a door (2) that is openably attached to the storage body (1) and closes the front opening leading to the storage body (R). , A circulation fan (5) that circulates the inside air of the inside (R), a cooling device (3) that cools the inside air, a temperature sensor (6) that detects the inside temperature (D), and a refrigerator. The target temperature zone is set based on the temperature setting unit (26) that accepts the input of the target temperature (D0) inside (R) and the target temperature (D0) input by the temperature setting unit (26), and the temperature inside the refrigerator. A cooling storage provided with a cooling device (3) and a control device (25) for controlling the operating state of the circulation fan (5) so that (D) is maintained within the target temperature range.
A cooling storage characterized in that the measured temperature (DM) at the measurement point according to the evaluation method according to claims 1 to 3 satisfies all of the following temperature conditions (i) to (iv).
<Temperature condition>
(I) (D0) -1 ° C ≤ (DM _AVE ) ≤ (D0) + 1 ° C
(Ii) (DM _MAX )-(DM _MIN ) ≤ 2 ° C
(Iii) (DM _ALLMAX )-(DM _ALLMIN ) ≤ 2 ° C
(Iv) (D0) + 1 ° C <(DM _ALLMAX ) <(D0) + 2 ° C

(D0): Target temperature (DM _AVE ): Average value of measurement temperature (DM) at _{each measurement point (DM MAX} ): Maximum temperature at each measurement point (DM _MIN ): Minimum temperature at each measurement point (DM _ALLMAX ): Maximum temperature at all measurement points (DM _ALLMIN ): Minimum temperature at all measurement points The cooling storage has at least two modes: a high-precision operation mode in which the target temperature zone is set within the target temperature ± 1 ° C, and an eco mode in which the target temperature zone is set within the target temperature ± 2 ° C. The control device (25) controls the operating states of the cooling device (3), the heating heater (4), and the circulation fan (5) according to the selection of these modes.
In the high-precision operation mode, the operation mode in the normal state where the internal temperature is within the target temperature range is defined as the normal operation mode, and in the high-precision operation mode, the operation mode when the internal temperature falls outside the target temperature range is defined as the operation mode. The cooling storage according to claim 4, wherein when the return mode is defined, the temperature inside the refrigerator (R) in the normal operation mode satisfies all of the temperature conditions (i) to (iv).

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