JP2017161184A - Vacuum cooling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vacuum cooling device 1 which continues an operation without stop when a product temperature sensor 21 is broken.SOLUTION: A vacuum cooling device 1 includes: a first decompression control unit 51 which controls an operation of a vacuum suction part 31 based on a detection temperature of a product temperature sensor 21; a second decompression control unit 52 which controls an operation of the vacuum suction part 31 based on a detection pressure of a pressure sensor 22; a product temperature sensor error judgement part 53 which judges whether an error occurs on the product temperature sensor 21; and a decompression control switching part 54 which stops an operation control of the vacuum suction part 31 by the first decompression control unit 51 and starts an operation control of the vacuum suction part 31 by the second decompression control unit 52 when the product temperature sensor error judgement part 53 judges that an error occurs in the product temperature sensor 21.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vacuum cooling device for cooling foods, foods, and the like.

  As disclosed in Patent Document 1, Patent Document 2, and the like, the inside of the treatment tank in which the object to be cooled is decompressed, moisture in the object to be cooled is vaporized, and the object to be cooled is cooled by the heat of vaporization. Vacuum cooling devices are known. In such a vacuum cooling device, a product temperature sensor is attached to an object to be cooled, and vacuum cooling is performed to a target temperature zone based on the temperature of the object to be cooled by the product temperature sensor.

  Patent Document 1 describes that pressure reduction control is performed by detecting the pressure in a processing tank, and pressure reduction control is performed by time control when a pressure sensor fails.

  Patent Document 2 describes that the product temperature of the same object to be cooled is detected by two product temperature sensors, and the cooling operation is controlled based on the detected temperature. It is described that when an abnormality occurs in one of the product temperature sensors, the cooling operation is controlled based on the temperature detected by the product temperature sensor in which no abnormality has occurred.

  In Patent Document 3, in order to prevent deterioration of the quality of the object to be cooled due to excessive cooling due to forgetting to insert the product temperature sensor, it is determined whether the product temperature sensor has been forgotten to be inserted before or after starting cooling. It is described that when forgetting is determined, the cooling of the object to be cooled is not started or the cooling is stopped.

In the alternative control based on the time described in Patent Document 1, the difference between the actual temperature of the object to be cooled and the required degree of decompression occurs, and depending on the object to be cooled, the quality is deteriorated due to the temperature difference and the yield is reduced due to scattering. There is a problem that happens.
The method described in Patent Document 2 is premised on including a plurality of product temperature sensors, and is applied to a cooling device that controls the cooling operation based on the temperature detected by one product temperature sensor. Can not.
The method described in Patent Document 3 does not start cooling of the object to be cooled or stops cooling when it is determined that the product temperature sensor is forgotten to be inserted, and does not disclose an alternative method of cooling control. Absent.

JP-A-11-137227 JP 2001-208617 A JP 2010-144981 A

  When controlling the cooling operation based on the temperature detected by the product temperature sensor, there was no method other than stopping the operation of the vacuum cooling device if the product temperature sensor failed or an abnormality such as a poor insertion occurred. .

  An object of the present invention is to provide a vacuum cooling device capable of continuing a cooling operation without stopping cooling control even when an abnormality such as a failure of a product temperature sensor or an insertion failure occurs.

  The present invention includes a cooling tank that accommodates an object to be cooled, a product temperature sensor that detects a temperature of the object to be cooled, a pressure sensor that detects a pressure inside the cooling tank, and a vacuum suction that depressurizes the cooling tank. A vacuum suction unit connected to the vacuum suction line, and a control unit, wherein the control unit controls the operation of the vacuum suction unit based on the temperature detected by the product temperature sensor. A product pressure sensor that determines whether or not an abnormality has occurred in the product temperature sensor, a second pressure reduction control unit that controls the operation of the vacuum suction unit based on a pressure reduction controller, a pressure detected by the pressure sensor When the abnormality determining unit and the product temperature sensor abnormality determining unit determine that an abnormality has occurred in the product temperature sensor, the operation control of the vacuum suction unit by the first pressure reduction control unit is stopped, and the second Operation of the vacuum suction unit by the decompression control unit A pressure reduction control switching unit which activates the control relates to a vacuum cooling apparatus comprising a.

  Preferably, the product temperature sensor abnormality determination unit determines whether or not an abnormality has occurred in the product temperature sensor based on a rate of change in temperature detected by the product temperature sensor.

  Preferably, the product temperature sensor abnormality determination unit determines that an abnormality has occurred in the product temperature sensor when the product temperature sensor does not output a detected temperature.

  The product temperature sensor abnormality determination unit preferably determines that an abnormality has occurred in the product temperature sensor when the temperature detected by the product temperature sensor indicates a value outside a predetermined range.

  According to the present invention, even if the product temperature sensor breaks down, as a backup, it can be switched to the pressure reduction control based on the pressure detected by the pressure sensor, and can be continuously operated without stopping the vacuum cooling device.

It is a mimetic diagram showing a schematic structure of one embodiment of vacuum cooling device 1 of the present invention. It is a functional block diagram which shows the structure of the control part 5 as an operation | movement determination part which concerns on this embodiment, and a control switching part. It is a flowchart which shows operation | movement of the vacuum cooling device 1 which concerns on this embodiment. It is a flowchart which shows operation | movement of the vacuum cooling device 1 which concerns on this embodiment.

  Hereinafter, a preferred embodiment of a vacuum cooling apparatus of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram showing a schematic configuration of an embodiment of a vacuum cooling device 1 of the present invention.

  As shown in FIG. 1, the vacuum cooling device 1 includes a cooling tank 2, a decompression unit 3, a decompression unit 4, and a control device 5.

  The cooling tank 2 accommodates an object 23 to be cooled. The cooling tank 2 includes an opening / closing door (not shown) for taking in and out the object 23 to be cooled, and the cooling tank 2 can be completely sealed by closing the opening / closing door. In this embodiment, the foodstuff is accommodated in the cooling tank 2 at the same time as the object 23 to be cooled.

  The cooling tank 2 is provided with a product temperature sensor 21 that detects the temperature of the food that is the object to be cooled 23 accommodated in the cooling tank 2. This product temperature sensor 21 measures the temperature of the part by being inserted into the food accommodated in the cooling tank 2.

  The cooling tank 2 is provided with a pressure sensor 22 for detecting the pressure in the cooling tank 2.

The decompression means 3 includes a vacuum suction part 31, and the vacuum suction part 31 is connected to the cooling tank 2 via a vacuum suction line 33.
The vacuum suction unit 31 includes, for example, a water ring vacuum pump.
The vacuum suction line 33 is preferably provided with a heat exchanger 32. A steam ejector (not shown) may be provided on the upstream side of the heat exchanger 32 in the decompression line 33.

  The heat exchanger 32 cools and condenses the food vapor in the vacuum suction line 33 and the vapor of the vapor ejector (when a vapor ejector is provided). The food vapor in the vacuum suction line 33 and the steam of the steam ejector are cooled and condensed in advance, thereby reducing the temperature of the fluid in the vacuum suction line 33 and reducing the volume of the fluid to be discharged. By doing so, the load of the vacuum suction part 31 can be reduced and the pressure reduction in the cooling tank 2 can be effectively achieved.

  The steam ejector sucks and discharges the fluid in the cooling tank 2 by ejecting steam. The pressure on the suction side of the vacuum suction unit 31 can be increased by the steam ejector, and the pressure in the cooling tank 2 can be effectively reduced.

The return pressure means 4 is means for introducing outside air into the decompressed cooling tank 2 to release the vacuum state and return the pressure. Specifically, the outside air is taken in through the filter 41 and can be supplied into the cooling tank 2 through the return pressure line 42.
In the middle of the return pressure line 42, a return pressure operation valve 43 for switching presence / absence of communication between the outside air and the inside of the cooling tank 2 is provided. Therefore, after the decompression means 3 is decompressed by the decompression means 3 with the decompression operation valve 43 closed, the decompression by the decompression means 3 is stopped, and the decompression operation valve 43 is opened, so that the cooling tank 2 The vacuum state inside can be released and returned to atmospheric pressure.

The return pressure operation valve 43 is configured such that its opening degree can be arbitrarily adjusted like a proportional control valve. Therefore, the pressure in the cooling tank 2 can be arbitrarily adjusted by adjusting the opening of the return pressure operation valve 43 when the pressure reducing means 3 depressurizes the cooling tank 2.
More specifically, the pressure in the cooling tank 2 can be easily adjusted by performing the pressure reducing operation by the pressure reducing means 3 while adjusting the opening of the return pressure operation valve 43.

  The control unit 5 controls the decompression means 3, the decompression means 4, and the like. In this embodiment, the product temperature sensor 21, the pressure sensor 22, the vacuum suction unit 31, and the return pressure operation valve 43 are connected to the control unit 5, and various controls can be performed by the control unit 5.

FIG. 2 is a functional block diagram illustrating a functional configuration of the control unit 5.
As shown in FIG. 2, the control unit 5 can continue the cooling operation without stopping the cooling control even when the product temperature sensor 21 fails or when an abnormality such as a poor insertion occurs. A first pressure reduction control unit 51, a second pressure reduction control unit 52, a product temperature sensor abnormality determination unit 53, and a pressure reduction control switching unit 54 are provided.

The first pressure reduction control unit 51 controls the operation of the vacuum suction unit 31 until the detected temperature reaches a preset target temperature based on the detected temperature of the product temperature sensor 21. Here, the target temperature is a target cooling temperature of the object 23 to be cooled.
The first depressurization control unit 51 stores the object to be cooled 23 in the cooling bath 2 and cools it at a pressure reduction speed set in advance as a standard speed. The degree of temperature drop over time, that is, the temperature change amount (temperature gradient) is measured, and the pressure reduction is performed while the opening degree of the return pressure operation valve 43 is adjusted based on the temperature change amount (temperature gradient) of the object 23 to be cooled. By performing the decompression operation by means 3, the decompression speed in the cooling bath 2 is adjusted. That is, when the temperature change amount is large, the first pressure reduction control unit 51 makes the pressure reduction rate in the cooling bath 2 slower than the standard pressure reduction rate, and when the temperature change amount is small, the first pressure reduction control unit 51 reduces the pressure reduction in the cooling bath 2. Based on the amount of change in temperature (temperature gradient) of the object 23 to be cooled so that the speed does not suddenly boil, the decompression means 3 performs decompression while adjusting the opening of the return pressure operation valve 43. By performing the operation, the pressure reducing speed in the cooling bath 2 is adjusted.
The first decompression control unit 51 measures a temperature change amount (temperature gradient) at a predetermined elapsed time from the start of measurement of the object 23 to be cooled, and a cooling load based on the measured temperature change amount (temperature gradient). The amount may be determined, and the decompression speed in the cooling tank 2 may be adjusted based on the cooling load amount.
The first depressurization control unit 51 cools the object 23 to be cooled, stops the depressurization by the depressurization means 3 and opens the return pressure operation valve 43 when the temperature detected by the product temperature sensor 21 reaches the target temperature. Thus, the vacuum state in the cooling tank 2 is released and returned to the atmospheric pressure.
Note that, depending on the characteristics of the object to be cooled 23 (for example, cooling characteristics such that it is difficult to be cooled), the first pressure reduction control unit 51 performs, for example, a return pressure operation valve after the temperature detected by the product temperature sensor 21 reaches the target temperature. By adjusting the opening degree of 43 and performing the pressure reducing operation by the pressure reducing means 3, the pressure detected by the pressure reducing means 3 is stopped after the temperature detected by the product temperature sensor 21 has maintained the target temperature for a predetermined time (maintenance time). Then, it may be configured to release the vacuum state in the cooling tank 2 and return to the atmospheric pressure by opening the return pressure operation valve 43. By doing so, it is possible to eliminate uneven cooling.

  As described above, the first pressure reduction control unit 51 adjusts the opening degree of the return pressure operation valve 43 based on the temperature change amount measured by the product temperature sensor 21 or the cooling load amount determined from the temperature change amount. On the other hand, the decompression operation by the decompression unit 3 is performed by adjusting the decompression speed in the cooling tank 2, and the decompression by the decompression unit 3 is stopped when the temperature detected by the product temperature sensor 21 reaches the target temperature.

The second decompression control unit 52 controls the operation of the vacuum suction unit 31 based on the pressure detected by the pressure sensor 22. Specifically, the second pressure reduction control unit 52 reduces the pressure until the internal pressure of the cooling tank 2 reaches a target pressure value calculated based on a preset target temperature.
Here, the target pressure value may be calculated as a saturation pressure corresponding to the target temperature. In addition, since the object to be cooled 23 is not necessarily cooled immediately, the saturation pressure value corresponding to the first target temperature obtained by subtracting a predetermined temperature ΔT (for example, 2 degrees) set in advance from the target temperature. It may be calculated.
For example, the second pressure reduction control unit 52 stores the object 23 to be cooled in the cooling tank 2 and cools the object 23 in the cooling tank 2 at a predetermined pressure reduction speed set in advance as a standard speed. By measuring the amount of change in pressure over a period of time and adjusting the opening of the return pressure operation valve 43 based on the amount of change in pressure of the object 23 to be cooled, the depressurization operation by the depressurization means 3 is performed. 2 is configured to adjust the decompression rate within 2. That is, when the pressure change amount is large, the second pressure reduction control unit 52 makes the pressure reduction rate in the cooling tank 2 slower than the standard pressure reduction rate, and when the pressure change amount is small, the second pressure reduction control unit 52 The pressure reducing means 3 performs the pressure reducing operation while adjusting the opening of the pressure reducing operation valve 43 based on the pressure change amount in the cooling tank 2 so as to make the speed faster than the standard pressure reducing speed so as not to bump. Thus, the pressure reducing speed in the cooling bath 2 is adjusted.
The second pressure reduction control unit 52 measures the amount of pressure change at a predetermined elapsed time from the start of measurement of the pressure in the cooling tank 2, determines the cooling load amount based on the measured amount of pressure change, and You may comprise so that the pressure reduction speed in the cooling tank 2 may be adjusted based on the amount of cooling loads.
The second decompression control unit 52 cools the object 23 to be cooled, and stops the decompression by the decompression unit 3 and opens the return pressure operation valve 43 when the detected pressure of the pressure sensor 22 reaches the target pressure.
Note that, according to the characteristics of the object to be cooled 23 (for example, cooling characteristics such that it is difficult to be cooled), the second pressure reduction control unit 52 returns the pressure-reducing operation valve 43 after the pressure in the cooling tank 2 reaches the target pressure value. The pressure in the cooling tank 2 is maintained at the target pressure value for a predetermined time (maintenance time) by performing a pressure reducing operation by the pressure reducing means 3 while adjusting the opening degree of the gas, and then the pressure reduction by the pressure reducing means 3 is stopped. Alternatively, the return pressure operation valve 43 may be opened to release the vacuum state in the cooling tank 2 and return it to atmospheric pressure. By doing so, it is possible to eliminate uneven cooling.

  As described above, the second pressure reduction control unit 52 adjusts the opening degree of the return pressure operation valve 43 based on the pressure change amount measured by the pressure sensor 22 or the cooling load amount determined from the pressure change amount. The decompression speed in the cooling tank 2 can be adjusted by performing a decompression operation by the decompression means 3.

  The product temperature sensor abnormality determination unit 53 determines whether or not an abnormality has occurred in the product temperature sensor 21. Typically, the product temperature sensor abnormality determination unit 53 determines that an abnormality has occurred in the product temperature sensor 21 when an abnormality signal from the product temperature sensor 21 is detected.

Further, the product temperature sensor abnormality determination unit 53 can be configured to determine whether an abnormality has occurred in the product temperature sensor 21 based on the rate of change of the temperature detected by the product temperature sensor 21.
For example, when the product temperature sensor abnormality determination unit 53 determines that the change rate of the detected temperature detected during a predetermined detection time (for example, 5 seconds) is smaller than the preset first determination temperature change rate, 23, it may be determined that the product temperature sensor 21 is not correctly inserted or the product temperature sensor 21 has been removed from the object to be cooled 23, and it is determined that an abnormality has occurred in the product temperature sensor 21.
Similarly, when the product temperature sensor abnormality determination unit 53 determines that the change rate of the detected temperature detected during the predetermined detection time is larger than the preset second determination temperature change rate, the product temperature sensor It may be determined that an abnormality has occurred in the product temperature sensor 21 by estimating that the product temperature sensor 21 has not been correctly inserted or the product temperature sensor 21 has been removed from the object 23 to be cooled.

  The product temperature sensor abnormality determination unit 53 may determine that an abnormality has occurred in the product temperature sensor when the product temperature sensor 21 does not output the detected temperature.

  Further, the product temperature sensor abnormality determination unit 53 causes an abnormality in the product temperature sensor 21 when the temperature detected by the product temperature sensor 21 is outside the measurement range and exceeds the temperature that the product temperature sensor 21 can normally determine. It may be determined that

The decompression control switching unit 54 stops the operation control of the vacuum suction unit 31 by the first decompression control unit 51 when the product temperature sensor abnormality determination unit 53 determines that an abnormality has occurred in the product temperature sensor 21. Thereafter, the vacuum control switching unit 54 performs vacuum suction by the second vacuum control unit 52 so as to reduce the pressure until the internal pressure of the cooling tank 2 reaches a target pressure value calculated based on a preset target temperature. The operation control of the unit 31 is started.
Here, the target pressure value calculated based on the preset target temperature may be calculated in advance by the control unit 5 when the target temperature is set. Further, the pressure reduction control switching unit 54 may calculate the target pressure value based on the target temperature. Alternatively, the second pressure reduction control unit 52 may calculate the target pressure value based on the target temperature.
By doing so, the second pressure reduction control unit 52 reduces the pressure until the internal pressure of the cooling tank 2 reaches the target pressure value. ,

Next, with reference to FIG.3 and FIG.4, operation | movement of the vacuum cooling device 1 which concerns on this embodiment is demonstrated. 3 and 4 are flowcharts showing an example of the operation of the vacuum cooling device 1 according to the present embodiment.
Here, a saturation pressure value P0 corresponding to a first target temperature (T0−ΔT) obtained by subtracting a preset predetermined temperature ΔT from a target temperature T0 that is a target cooling temperature of the object 23 is calculated in advance. I shall keep it.

In step ST1, after the object to be cooled is accommodated in the cooling tank 2 and the door is closed, the saturation pressure value corresponding to the first target temperature (T ₀ −ΔT) is based on the target temperature T ₀ inputted in advance. A certain target pressure value P ₀ is calculated.

  In step ST2, when the operation switch is turned on, the first pressure reduction control unit 51 activates the vacuum cooling device 1 and starts pressure reduction (cooling).

In step ST3, the first pressure reduction control unit 51 based on the detected temperature of the material temperature sensor 21, so that the detected temperature reaches the target temperature T _0, performs the decompression control by pressure reducing means 3.

  In step ST <b> 4, the product temperature sensor abnormality determination unit 53 determines whether or not an abnormality has occurred in the product temperature sensor 21. When it determines with abnormality having occurred in the product temperature sensor 21 (in the case of Yes), it moves to step ST10. When it is determined that no abnormality has occurred in the product temperature sensor 21 (in the case of No), the process proceeds to step ST5.

In step ST5, the first pressure reduction control unit 51 determines whether or not the temperature detected by the material temperature sensor 21 reaches the target temperature T _0. When it reaches the target temperature _{T 0} (the case of Yes) proceeds to step ST6. When it has not reached the target temperature _{T 0} (the case of No), the process returns to step ST3.

  In step ST6, the first pressure reduction control unit 51 adjusts the opening degree of the return pressure operation valve 43 so that the temperature detected by the product temperature sensor 21 is maintained at the target temperature for a predetermined time (maintenance time). The decompression operation according to 3 is performed.

  In step ST7, the first pressure reduction control unit 51 stops the pressure reduction by the pressure reducing means 3.

  In step ST8, the 1st pressure reduction control part 51 opens the pressure-reduction operation valve 43, cancels | releases the vacuum state in the cooling tank 2, and returns it to atmospheric pressure.

(Processing when an abnormality occurs in the product temperature sensor 21)
In step ST10, the decompression control switching unit 54 stops the decompression control by the decompression unit 3 by the first decompression control unit 51.

  In step ST11, the decompression control switching unit 54 activates the second decompression control unit 52.

In step ST12, the second pressure reduction control unit 52 based on the pressure detected by the pressure sensor 22, so that the detected pressure reaches the target pressure P _0, performs the decompression control by pressure reducing means 3.

In step ST13, the second pressure reduction control unit 52 determines whether the detected pressure by the pressure sensor 22 reaches the target pressure value P _0. When it reaches the target pressure _{P 0} (case of Yes) proceeds to step ST14. If you do not reach the target pressure _{P 0} (case of No), the process returns to step ST12.

In step ST14, the second pressure reduction control unit 52, a predetermined time, so as to maintain the pressure in the cooling tank 2 to the target pressure value P _0, while adjusting the degree of opening of the pressure recovery operation valve 43, by the pressure reducing means 3 Perform decompression.

  In step ST15, the second pressure reduction control unit 52 stops the pressure reduction by the pressure reduction means 3.

  In step ST16, the 2nd pressure reduction control part 52 opens the pressure-reduction operation valve 43, cancels | releases the vacuum state in the cooling tank 2, and returns it to atmospheric pressure.

Note that step ST6 or step ST14 may be omitted according to the characteristics of the object 23 to be cooled (for example, cooling characteristics such that it is easily cooled). That is, in step ST5, (case of Yes) when it reaches the target temperature _{T 0} may be configured to move to step ST7. Further, in step ST13, (case of Yes) when it reaches the target pressure _{P 0} may be configured to move to step ST15.

As described above, the vacuum cooling device 1 of the present embodiment uses the first pressure reduction control unit 51 that controls the operation of the vacuum suction unit 31 and the detected pressure of the pressure sensor 22 based on the temperature detected by the product temperature sensor 21. Based on the second pressure reduction control unit 52 that controls the operation of the vacuum suction unit 31, a product temperature sensor abnormality determination unit 53 that determines whether an abnormality has occurred in the product temperature sensor 21, and a product temperature sensor abnormality determination When it is determined by the unit 53 that an abnormality has occurred in the product temperature sensor 21, the operation control of the vacuum suction unit 31 by the first pressure reduction control unit 51 is stopped, and the operation of the vacuum suction unit 31 by the second pressure reduction control unit 52 is stopped. And a decompression control switching unit 54 for starting the control.
Thereby, even if the product temperature sensor 21 breaks down, it can switch to the pressure reduction control based on the detected pressure of the pressure sensor 22 as a backup, and can be continuously operated without stopping the vacuum cooling device 1.

  Further, the product temperature sensor abnormality determination unit 53 of the vacuum cooling device 1 according to the present embodiment determines whether or not an abnormality has occurred in the product temperature sensor 21 based on the rate of change of the temperature detected by the product temperature sensor 21.

  Further, the product temperature sensor abnormality determination unit 53 of the vacuum cooling device 1 of the present embodiment determines that an abnormality has occurred in the product temperature sensor 21 when the product temperature sensor 21 does not output the detected temperature.

Further, the product temperature sensor abnormality determination unit 53 of the vacuum cooling device 1 according to the present embodiment determines that an abnormality has occurred in the product temperature sensor 21 when the temperature detected by the product temperature sensor 21 indicates a value outside a predetermined range. To do.
Thereby, the abnormality of the product temperature sensor 21 can be detected at an early stage, and the pressure reduction control based on the pressure detected by the pressure sensor 22 can be switched.

  As mentioned above, although this invention was demonstrated by embodiment, it cannot be overemphasized that this invention can be variously implemented in the range which does not change the main point.

[Modification]
In the present embodiment, the vacuum suction unit 31 may apply a water ring vacuum pump as a vacuum pump. The water-sealed vacuum pump forms a liquid ring inside by supplying sealed water, and sucks and discharges air by the rotation of the liquid ring.
Further, instead of or in addition to this, a steam ejector may be provided.

DESCRIPTION OF SYMBOLS 1 Vacuum cooling device 2 Cooling tank 21 Product temperature sensor 22 Pressure sensor 3 Pressure reduction means 31 Vacuum suction part 32 Heat exchanger 33 Vacuum suction line 4 Pressure recovery means 41 Filter 42 Pressure recovery line 43 Pressure recovery operation valve 5 Control part 51 1st Decompression controller 52 Second decompression controller 53 Product temperature sensor abnormality determination unit 54 Depressurization control switching unit

Claims (4)

A cooling tank for storing an object to be cooled;
A product temperature sensor for detecting the temperature of the object to be cooled;
A pressure sensor for detecting the pressure inside the cooling tank;
A vacuum suction line for decompressing the cooling tank;
A vacuum suction unit connected to the vacuum suction line;
A control unit;
With
The controller is
A first pressure reduction control unit that controls the operation of the vacuum suction unit based on the temperature detected by the product temperature sensor;
A second pressure reduction control unit for controlling the operation of the vacuum suction unit based on the detected pressure of the pressure sensor;
A product temperature sensor abnormality determination unit for determining whether an abnormality has occurred in the product temperature sensor; and
When the product temperature sensor abnormality determination unit determines that an abnormality has occurred in the product temperature sensor, the operation control of the vacuum suction unit by the first pressure reduction control unit is stopped, and the second pressure reduction control unit performs the operation A depressurization control switching unit for starting the operation control of the vacuum suction unit;
A vacuum cooling device comprising: The product temperature sensor abnormality determination unit
The vacuum cooling apparatus according to claim 1, wherein it is determined whether an abnormality has occurred in the product temperature sensor based on a rate of change in temperature detected by the product temperature sensor. The product temperature sensor abnormality determination unit
The vacuum cooling device according to claim 1 or 2, wherein when the product temperature sensor does not output a detected temperature, it is determined that an abnormality has occurred in the product temperature sensor. The product temperature sensor abnormality determination unit
The vacuum cooling device according to any one of claims 1 to 3, wherein when the temperature detected by the product temperature sensor indicates a value outside a predetermined range, it is determined that an abnormality has occurred in the product temperature sensor. .

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