Vacuum microwave thawing machine

Abstract

In a vacuum microwave thawing machine, the accuracy of the notification of thawing time and the remaining time is improved. [Solution] When transitioning from the depressurization process to the repressurization process, (S5) Target vacuum P O and equilibrium vacuum P during the current thawing cycle k The difference between this and the target vacuum level is ΔP. O , and (S6) equilibrium vacuum P during the current thawing cycle. k and equilibrium vacuum P during the previous thawing cycle k-1 The difference between this and the previous vacuum level is ΔP. k Based on both of these, (S10) a first remaining time estimation process is made possible to estimate the remaining thawing time.

Claims

1. A vacuum microwave thawing machine comprising: a thawing chamber for containing the object to be thawed; a vacuum pump for reducing the pressure inside the thawing chamber; a pressure regulating valve for restoring the pressure inside the thawing chamber; a microwave generator for generating microwaves to irradiate the thawing chamber; and a control device for controlling the vacuum microwave thawing machine, The control device is The thawing control involves alternately performing a depressurization step, in which the vacuum pressure inside the thawing chamber is reduced to an equilibrium state using the vacuum pump, and a repressurization step, in which the vacuum pressure at the equilibrium state is restored to an upper limit using the pressure regulating valve, while simultaneously irradiating the chamber with microwaves from the microwave generator at intervals. This repeatedly performs microwave heating and sublimation cooling in a reduced pressure state, and this thawing cycle consisting of microwave heating and sublimation cooling is repeated until the equilibrium vacuum reaches a target vacuum to thaw the object to be thawed. A vacuum microwave thawing machine is capable of performing a first remaining time estimation process to estimate the remaining thawing time when transitioning from the depressurization process to the repressurization process, based on both the difference between the target vacuum level and the equilibrium vacuum level during the current thawing cycle, which is the difference between the target vacuum level and the equilibrium vacuum level during the current thawing cycle, and the difference between the equilibrium vacuum level during the current thawing cycle and the equilibrium vacuum level during the previous thawing cycle, which is the difference between the equilibrium vacuum level during the current thawing cycle and the equilibrium vacuum level during the previous thawing cycle.

2. The vacuum microwave thawing machine according to claim 1, wherein the first remaining time estimation process estimates the remaining thawing time to be the set remaining time when the difference in vacuum degree relative to the target is less than or equal to the first difference threshold relative to the target, and the difference in vacuum degree relative to the previous time is greater than or equal to the difference threshold relative to the previous time.

3. The vacuum microwave thawing machine according to claim 2, wherein the remaining time for setting corresponds to the time required for the thawing cycle to be performed twice.

4. The control device estimates the thawing time based on the weight of the object to be thawed before the start of the first thawing cycle, and displays the thawing time on a display device. The vacuum microwave thawing machine according to claim 2 or 3, wherein, until the remaining thawing time is estimated to be the set remaining time by the first remaining time estimation process, the remaining thawing time is displayed on the display device by subtracting the elapsed time since the start of the thawing cycle from the thawing time, and when the remaining thawing time is estimated to be the set remaining time by the first remaining time estimation process, the set remaining time is displayed on the display device.

5. The vacuum microwave thawing machine according to claim 4, wherein the remaining thawing time displayed on the display device is updated each time a predetermined amount of time has elapsed until the remaining thawing time is estimated to be the set remaining time by the first remaining time estimation process.

6. The vacuum microwave thawing machine according to claim 2 or 3, wherein, after the remaining thawing time is estimated to be the set remaining time by the first remaining time estimation process, if the difference in vacuum degree relative to the target when transitioning from the depressurization process to the repressurization process is less than or equal to a second target difference threshold which is smaller than the first target difference threshold, a second remaining time estimation process is performed to estimate that the remaining thawing time is less than or equal to the normal single microwave irradiation time.

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