Apparatus and Method For Thawing Foodstuff

Abstract

An apparatus and method for thawing foodstuff that includes a thawing chamber for accommodating the foodstuff, the thawing chamber includes a sensor for sensing a level of frozenness of the foodstuff in the thawing chamber, the sensor includes a microwave transmitter and a microwave receiver that is spaced from the microwave transmitter, the microwave receiver configured to receive a transmission signal transmitted by the microwave transmitter, the microwave transmitter and the microwave receiver are arranged inside the thawing chamber such that the foodstuff is, at least temporarily, situated between the microwave transmitter and the microwave receiver during a thawing process carried out with the apparatus.

Claims

1.-17. (canceled)

18. An apparatus for thawing foodstuff comprising a thawing chamber for accommodating the foodstuff, the thawing chamber comprises a sensor for sensing a level of frozenness of the foodstuff in the thawing chamber, the sensor comprising a microwave transmitter and a microwave receiver that is spaced from the microwave transmitter, the microwave receiver configured to receive a transmission signal transmitted by the microwave transmitter, the microwave transmitter and the microwave receiver are arranged inside the thawing chamber such that the foodstuff is, at least temporarily, situated between the microwave transmitter and the microwave receiver during a thawing process carried out with the apparatus.

19. The apparatus according to claim 18, wherein the apparatus comprises a base, and the thawing chamber is arranged movably with respect to the base such that the thawing chamber is movable with respect to the base during the thawing process.

20. The apparatus according to claim 19, wherein the sensor is arranged at a fixed location inside the thawing chamber such that the sensor is movable together with the thawing chamber.

21. The apparatus according to claim 19, wherein the apparatus or the sensor comprises a position detector for detecting a position of the thawing chamber or a position of the sensor with respect to the base, wherein the apparatus is configured to sense the level of frozenness of the foodstuff depending on the position detected by the position detector.

22. The apparatus according to claim 18, wherein the apparatus or the sensor includes a processing unit that is configured to analyze an amplitude of the transmission signal received by the microwave receiver.

23. The apparatus according to claim 22, wherein the processing unit is configured to analyze a phase of the transmission signal received by the microwave receiver, or to analyze a phase difference between a signal transmitted by the microwave transmitter and the transmission signal received by the microwave receiver.

24. The apparatus according to claim 18, wherein the sensor comprises an electrical energy storage or a battery.

25. The apparatus according to claim 18, wherein the thawing chamber comprises one or more mixing elements that are movably or rotatably arranged inside the thawing chamber.

26. The apparatus according to claim 18, wherein a steam generator is connected to the thawing chamber to feed steam into the thawing chamber.

27. The apparatus according to claim 18, wherein a vacuum generator is connected to the thawing chamber to create a vacuum inside the thawing chamber.

28. The apparatus according to claim 18, wherein a controller is connected to the sensor via a communication link or a wireless communication link, the controller is configured to stop the thawing process depending on the level of frozenness detected by the sensor.

29. A method for thawing foodstuff in a thawing apparatus comprising a thawing chamber for accommodating the foodstuff, the thawing chamber includes a sensor for sensing a level of frozenness of the foodstuff accommodated in the thawing chamber, the sensor comprising a microwave transmitter and a microwave receiver that is spaced from the microwave transmitter, the method comprising: thawing the foodstuff in the thawing chamber, wherein the foodstuff is, at least temporarily, situated between the microwave transmitter and the microwave receiver of the sensor; and measuring a transmission signal transmitted by the microwave transmitter using the microwave receiver.

30. The method according to claim 29, wherein the apparatus comprises a base and the method comprises moving or rotating the thawing chamber with respect to the base during the thawing step.

31. The method according to claim 30, wherein the method comprises detecting a position of the thawing chamber with respect to the base and measuring the transmission signal depending on the detected position of the thawing chamber.

32. The method according to claim 31, wherein the method comprises stopping movement of the thawing chamber when the thawing chamber is in a position in which the foodstuff is situated between the microwave transmitter and the microwave receiver at least for a predetermined period.

33. The method according to claim 29, wherein the method comprises determining a level of frozenness based on the transmission signal received by the microwave receiver when the thawing chamber is in a position in which the foodstuff is situated between the microwave transmitter and the microwave receiver.

34. The method according to claim 29, wherein the thawing step is stopped when a detected level of frozenness reaches a predetermined level.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0035] FIG. 1 shows an apparatus according to an embodiment of the present invention in a tumbling and/or thawing position;

[0036] FIG. 2 shows the apparatus of FIG. 1 in a loading position;

[0037] FIG. 3 shows the apparatus of FIG. 1 in an unloading position;

[0038] FIG. 4 shows the interior of the thawing chamber of the apparatus of FIG. 1;

[0039] FIG. 5 shows a sectional view of the thawing chamber of FIG. 4;

[0040] FIG. 6 shows a block diagram of the sensor of the apparatus depicted in FIG. 1;

[0041] FIG. 7 shows the amplitude of a transmission signal vs. temperature; and

[0042] FIG. 8 shows the phase of a transmission signal vs. temperature.

DETAILED DESCRIPTION

[0043] The present invention will be described with respect to embodiments and with reference to the figures, but the invention is not limited thereto but only by the claims. The figures described are only schematic and is non-limiting. In the figures, the size of some of the elements may be exaggerated and not drawn on scale for illustrative purposes.

[0044] FIGS. 1, 2 and 3 depict an apparatus 1 for thawing foodstuff that is implemented as a thawing tumbler. The apparatus 1 comprises a base 2 and a thawing chamber 3 for accommodating foodstuff, which is moveable with respect to the base 2. The thawing chamber 3 may be tilted to be transferred between a first position in which an opening 4 of the thawing chamber 3 is in an upright position, see FIG. 1 and FIG. 2, into a second position in which the opening 4 is directed downwards, see FIG. 3. When the thawing chamber 3 is in this first position, the thawing chamber 3 may be filled with foodstuff. The second position may be taken for discharging the foodstuff from the thawing chamber 3.

[0045] The thawing chamber 3 is further movable with respect to the base 2 wherein the opening 4 either stays in its upward or downward directed position. In particular, the thawing chamber 3 may be rotated about an axis of rotation R, preferable for massaging or tumbling the foodstuff accommodated in the thawing chamber 3. According to the exemplary embodiment, the thawing chamber 3 is essentially cylindrical, and the axis of rotation R is the cylinder axis of the essentially cylindrical thawing chamber.

[0046] The thawing chamber will in detail be explained with reference to FIGS. 5 and 6. The thawing chamber 3 includes a sensor 10 for sensing a level of frozenness of the foodstuff accommodated in the thawing chamber 3, which sensor is arranged at a fixed location inside the thawing chamber 3 such that the sensor 10 is movable, in particular rotatable, together with the thawing chamber 3. The sensor 10 comprises a first antenna that serves as a microwave transmitter 11 and a second antenna which serves as a microwave receiver 12 that is spaced from the microwave transmitter 11. The microwave receiver 12 is configured to receive a transmission signal transmitted by the microwave transmitter 11. The sensor 10 is integrated into a sidewall of the thawing chamber 3 so that the microwave transmitter 11 and the microwave receiver 12 both face the interior of the thawing chamber 3. Both, the microwave transmitter 11 and the microwave receiver 12 are arranged inside the thawing chamber 3 such that the foodstuff is, at least temporarily, situated between the microwave transmitter 11 and the microwave receiver 12 during a thawing process carried out with the apparatus 1.

[0047] As depicted in FIG. 6, the sensor 10 comprises the microwave transmitter 11, the microwave receiver 12. The sensor 10 further comprises an electrical energy storage 13, preferably a battery. Another element of the sensor 10 is processing unit 14 connected to the microwave transmitter 11 and the microwave receiver 12 as well as the electrical energy storage 13.

[0048] The apparatus further includes a position detector 15 for detecting a position of the thawing chamber 3, in particular a position of the sensor 10, with respect to the base 2. The position detector 15 may be implemented as part of the sensor 10 as depicted in FIG. 6. Alternatively, the position detector 15 may be separate from the sensor 10, e.g. attached to the base 2 of the apparatus 1. According to the shown embodiment, the apparatus 1 is configured to sense the level of frozenness depending on the position of the thawing chamber 3 detected by the position detector 15. Here, the level of frozenness is only sensed if the position of the thawing chamber 3 detected by the position detector 15 lies within a predefined range of positions. The predefined range of positions preferably includes one or more positions in which the sensor 10 of the thawing chamber 3 is situated in a lower area of the thawing chamber 3 so that foodstuff is forced towards the sensor 10, in particular between the microwave transmitter 11 and the microwave receiver 12, by the force of gravity. Such a position is depicted in FIG. 4. In this position, it may be ensured that foodstuff is present between the microwave transmitter 11 and the microwave receiver 12 in order to correctly determine the level of frozenness of the foodstuff.

[0049] The processing unit 14 is configured to analyze the amplitude of the transmission signal received by the microwave receiver 12. An exemplary measurement of an output signal of the sensor 10 vs. temperature is shown in FIG. 7. The output signal 10 is proportional to the amplitude of the transmission signal received by the microwave receiver 12, in particular proportional to the ratio of the amplitude of the transmission signal received by the microwave receiver 12 to the signal transmitted by the microwave transmitter 11. In the transition phase between solid and liquid—here the temperature range between −5° C. and 5° C.— the amplitude of the transmission signal changes considerably, so that a change in level of frozenness can be detected.

[0050] Optionally, the processing unit is further configured to analyze a phase shift of the transmission signal received by the microwave receiver 12. An exemplary phase shift measurement vs. temperature is shown in FIG. 8. The phase of the transmission signal as received by the microwave receiver 12 may be defined relative to the phase of the signal transmitted by the microwave transmitter 11. Similar to the effect shown in FIG. 7 for the amplitude, the phase changes considerably in the transitional phase between solid and liquid—here the temperature range between −5° C. and 5° C.

[0051] The apparatus 1 further includes a controller that is connected to the sensor 10 via a communication link, preferably a wireless communication link, wherein the controller 10 is configured to stop the thawing process depending on the level of frozenness detected by the sensor 10.

[0052] According to an alternative embodiment not shown in the figures, the apparatus may be provided in the form of a thawing mixer. The thawing mixer may include a stationary thawing chamber with movable mixing elements. The sensor may be arranged in the bottom region of the thawing chamber so that the space between the microwave transmitter and the microwave receiver is filled with foodstuff with high probability.

[0053] The aforementioned embodiments of apparatuses 1 for thawing foodstuff include a thawing chamber 3 includes a sensor 10 for sensing a level of frozenness of the foodstuff accommodated in the thawing chamber 3. The sensor 10 comprises a microwave transmitter 11 and a microwave receiver 12 that is spaced from the microwave transmitter 11, the microwave receiver 12 further being configured to receive a transmission signal transmitted by the microwave transmitter 11. The microwave transmitter 11 and the microwave receiver 12 are arranged inside the thawing chamber 3 such that the foodstuff is, at least temporarily, situated between the microwave transmitter 11 and the microwave receiver 12 during a thawing process carried out with the apparatus 1. Thereby, the level of frozenness of foodstuff accommodated in the thawing chamber 3 can be reliably measured.

REFERENCE SIGNS

[0054] 1 apparatus for thawing foodstuff [0055] 2 base [0056] 3 thawing chamber [0057] 4 opening [0058] 5 lid [0059] 6 baffle [0060] 10 sensor [0061] 11 transmitter [0062] 12 receiver [0063] 13 energy storage [0064] 14 processing unit [0065] 15 position detector [0066] R axis of rotation