Patent Description:
During the freezing process of food, the quality of food is maintained. However, the frozen food needs to be heated before processing or eating. In order to facilitate a user freezing and heating food, in the prior art, food is generally thawed by providing an electromagnetic wave heating unit in a refrigerating and freezing apparatus such as a refrigerator.

For instance, <CIT> discloses a microwave heating apparatus and methods of controlling cooling of a microwave heating apparatus. The microwave heating apparatus typically includes a microwave source for generating microwaves, a cooling unit for cooling the microwave source and a control unit. According to one embodiment, the control unit is configured to determine the efficiency of the microwave source and then to control the cooling based on the determined efficiency. The methods and the microwave heating apparatuses of the present invention are advantageous with respect to energy consumption.

<CIT> teaches a control circuit of a microwave oven. The rotating speed of a fan is associated with the output power of a magnetron to improve the efficiency of the microwave oven. The control circuit of the microwave oven comprises a control portion, a frequency changer, the magnetron and the cooling fan. The control portion is used for outputting a pulse width modulated signal. The frequency changer is connected with the control portion so as to receive the pulse width modulated signal, the magnetron is connected with the frequency changer, and the cooling fan is connected with the control portion so as to receive the pulse width modulated signal.

<CIT> discloses a microwave oven with a variable speed motor (FM) for driving its cooling fan. The speed of the motor is linked to the output power of the oven so that the fan rotates quicker for high power operation than for low power operation.

<CIT> relates to equipment for cooling and freezing, in particular to a refrigeration and freezing device. The refrigerating and freezing device comprises a housing in which at least one storage compartment with a heating cavity is formed, and an electromagnetic heating device equipped with an electromagnetic generation module. In the upper part of the housing there is a groove for placement with an upwardly directed open part closed by a lid. Holes are formed in the lid for dissipating heat, configured to provide communication between the area for placement and the external environment in which the housing is located. The electromagnetic generation module is located in the placement area. In the area for placement, a fan is additionally installed to dissipate heat from the electromagnetic generation module.

<CIT> provides a heating device and a refrigerator with the same. The heating device comprises a cylinder provided with a pick-and-place opening, a door body used for opening and closing the pick-and-place opening, an electromagnetic generation module used for generating electromagnetic wave signals and a radiation antenna. The radiation antenna is arranged to be electrically connected with the electromagnetic generation module so as to generate electromagnetic waves with corresponding frequencies according to the electromagnetic wave signals. The heating device further comprises a signal processing, measuring and controlling circuit for measuring and controlling electromagnetic wave signals. And the signal processing and measurement and control circuit is electrically connected with the electromagnetic generation module and is arranged at the rear lower part in the cylinder body, so that the cylinder body has a larger storage space, and the circuit can be prevented from being damaged due to over-high food when the storage drawer is used for containing the food.

However, an electromagnetic wave generation system of the heating unit may generate more heat in a working process, which not only causes temperature fluctuation of a storage compartment and influences the preservation quality of food materials in the storage compartment, but also can reduce the working efficiency of the electromagnetic wave generation system. The service life of an electric device may be shortened seriously if the heating unit is kept in a high-temperature state for a long time.

An object of a first aspect of the present disclosure is to overcome at least one technical drawback in the prior art and to provide a control method for an electromagnetic wave heating unit.

A further object of the first aspect of the present disclosure is to reduce energy consumption.

An object of a second aspect of the present disclosure is to provide a heating unit.

An object of a third aspect of the present disclosure is to provide a refrigerating and freezing apparatus having the heating unit.

A further object of the third aspect of the present disclosure is to improve the cooling efficiency of an electromagnetic wave generation system.

According to the invention, as defined in claim <NUM>, provided is a control method for a heating unit disposed within a refrigerating and freezing apparatus, the heating unit includes a cylinder configured to contain an item to be treated, and an electromagnetic wave generation system of which at least one part is disposed in the cylinder or accessed into the cylinder, the electromagnetic wave generation system including an electromagnetic wave generation module configured to generate an electromagnetic wave signal and a cooling fan configured to cool the electromagnetic wave generation module, wherein the control method includes:.

Optionally, the electromagnetic wave generation module includes a frequency source, a power amplifier and a processing unit; and the control method further includes:.

Optionally, after the step of controlling the frequency source and the power amplifier to stop working, the control method further includes:
controlling the cooling fan to work at a rated rotation speed for a first preset time, and controlling the cooling fan to stop working after the first preset time. The claimed subject-matter is defined by the claims.

The above and other objects, advantages and features of the present disclosure will become more apparent to those skilled in the art from the following detailed description of specific embodiments thereof taken in conjunction with the accompanying drawings.

Some specific embodiments of the present disclosure will be described in detail hereinafter by way of example and not by way of limitation with reference to the accompanying drawings. The same reference numerals in the drawings identify the same or similar elements or parts. Those skilled in the art will appreciate that the drawings are not necessarily drawn to scale. In the drawings:.

<FIG> is a schematic exploded view of a refrigerating and freezing apparatus <NUM> according to an embodiment of the present disclosure. <FIG> is a schematic structural view of a heating unit <NUM> according to an embodiment of the present disclosure. Referring to <FIG> and <FIG>, the refrigerating and freezing apparatus <NUM> may include a cabinet <NUM> defining at least one storage compartment, at least one door configured to open and close the at least one storage compartment, a heating unit <NUM> and a controller. In the present disclosure, the refrigerating and freezing apparatus <NUM> may be an apparatus with a refrigerating or freezing function such as a refrigerator, a freezer, a cooler, a wine cabinet and so on.

The cabinet <NUM> may include a liner defining at least one storage compartment, an outer tank and a heat insulating layer disposed between the liner and the outer tank.

The heating unit <NUM> may include a cylinder <NUM> disposed in one storage compartment of the cabinet <NUM>, a door and an electromagnetic wave generation system.

Specifically, the cylinder <NUM> may define a heating chamber configured to contain an item to be treated <NUM>, and a pick-and-place opening may be formed in the front wall of the heating chamber and is configured to pick and place the item to be treated <NUM>.

The door may be mounted with the cylinder <NUM> together by an appropriate method, such as connection by a slide track and connection in a hinged manner, and is configured to open and close the pick-and-place opening.

At least one part of the electromagnetic wave generation system may be disposed in the cylinder <NUM> or accessed into the cylinder <NUM> to generate an electromagnetic wave in the cylinder <NUM> to heat the item to be heated <NUM>.

The cylinder <NUM> and the door may be respectively provided with electromagnetic shielding features, so that the door is in conductive connection with the cylinder <NUM> when the door is closed to prevent electromagnetic leakage.

<FIG> is a schematic structural view of a controller in <FIG>. Referring to <FIG>, the controller <NUM> may include a processing unit <NUM> and a storage unit <NUM>. A computer program <NUM> is stored in the storage unit <NUM>. The computer program <NUM> is configured to implement the control method according to an embodiment of the present disclosure when the computer program is executed by the processing unit <NUM>.

In some embodiments, the electromagnetic wave generation system may include an electromagnetic wave generation module <NUM>, a power supply module <NUM>, a radiating antenna <NUM>, and a matching module <NUM>.

The electromagnetic wave generation module <NUM> may be configured to generate an electromagnetic wave signal. <FIG> is a schematic structural view of the electromagnetic wave generation module <NUM> in <FIG>. Referring to <FIG>, in some embodiments, the electromagnetic wave generation module <NUM> may include a frequency source <NUM>, a power amplifier <NUM> and a processing unit <NUM>.

The power supply module <NUM> may be disposed to be electrically connected to the electromagnetic wave generation module <NUM> so as to provide electric energy for the electromagnetic wave generation module <NUM>, and then the electromagnetic wave generation module <NUM> generates the electromagnetic wave signal.

The radiating antenna <NUM> may be disposed in the cylinder <NUM> and is electrically connected to the electromagnetic wave generation module <NUM> so as to generate an electromagnetic wave with a corresponding frequency according to the electromagnetic wave signal to heat the item to be treated <NUM> in the cylinder <NUM>.

The matching module <NUM> may be connected between the electromagnetic wave generation module <NUM> and the radiating antenna <NUM> in series, and is configured to adjust load impedance of the electromagnetic wave generation module <NUM> by means of adjusting self impedance to achieve load matching and improve heating efficiency.

In some further embodiments, the cylinder <NUM> may be made of metal to serve as a receiving pole of the radiating antenna <NUM>. In the embodiments, the cylinder <NUM> itself is an electromagnetic shielding feature of the cylinder <NUM>.

In other further embodiments, the electromagnetic wave generation system further includes a receiving polar plate which is opposite to the radiating antenna <NUM> and electrically connected to the electromagnetic wave generation module <NUM>. In the embodiments, the inner wall of the cylinder <NUM> may be coated with a metal coating or attached with a metal net and the like as the electromagnetic shielding feature of the cylinder <NUM>.

<FIG> is a schematic partial cross-sectional view of the refrigerating and freezing apparatus <NUM> as shown in <FIG>. Referring to <FIG>, particularly, the heating unit <NUM> may further include at least one cooling fan <NUM> configured to cool the electromagnetic wave generation module <NUM> and the power supply module <NUM>. In the present disclosure, the electromagnetic wave generation module <NUM> and the power supply module <NUM> are cooled simultaneously by means of the cooling fan <NUM>; thus, efficient cooling on the electromagnetic wave generation module <NUM> and the power supply module <NUM> may be realized, furthermore, occupied space is reduced, and the storage space of the refrigerating and freezing apparatus <NUM> is expanded.

In the present disclosure, the number of the cooling fans <NUM> may be one, two, or more than two. For the convenience of understanding of the present disclosure, the present disclosure will be described hereinafter by taking one cooling fan <NUM> as an example.

In some embodiments, the refrigerating and freezing apparatus <NUM> may further include cooling fins <NUM> thermally connected to the electromagnetic wave generation module <NUM> to increase the cooling area of the electromagnetic wave generation module <NUM>, and then the cooling efficiency of the electromagnetic wave generation module <NUM> is improved.

The cooling fins <NUM> may include a plurality of rib plates perpendicular to the electromagnetic wave generation module <NUM>, namely, each rib plate extends from the electromagnetic wave generation module <NUM> towards a direction away from the electromagnetic wave generation module <NUM>, and is perpendicular to a surface where the rib plate is mounted.

The cooling fins <NUM> may further include a substrate integrated with the plurality of rib plates, and the substrate is configured to be thermally connected to the electromagnetic wave generation module <NUM>.

The cooling fan <NUM> may be disposed on sides of the cooling fins <NUM> away from the electromagnetic wave generation module <NUM>, and is disposed to blow out air flow towards the electromagnetic wave generation module <NUM>. Namely, the electromagnetic wave generation module <NUM> is disposed downstream of the cooling fan <NUM> to reduce wind resistance, and the cooling efficiency of the electromagnetic wave generation module <NUM> is improved.

The extending direction of the plurality of rib plates may further be disposed to be perpendicular to a direction of the electromagnetic wave generation module <NUM> close to the power supply module <NUM>, so as to reduce influences of heat generated by the electromagnetic wave generation module <NUM> on the power supply module <NUM>.

At least one rib plate thermally connected to the middle of the electromagnetic wave generation module <NUM> is provided with an accommodating portion recessed towards a direction close to the electromagnetic wave generation module <NUM>.

The cooling fan <NUM> may be disposed in the accommodating portion. A projection of the cooling fan <NUM> in an extending direction perpendicular to the plurality of rib plates is at least located in one of the rib plates, so as to further reduce influences of the heat on the power supply module <NUM> and further improve the cooling efficiency of the electromagnetic wave generation module <NUM>.

The cooling fan <NUM> may be disposed to suck air flow via the power supply module <NUM> and prompt the air flow to be blown out towards the electromagnetic wave generation module <NUM>, so as to improve the cooling efficiency of the electromagnetic wave generation module <NUM> and the power supply module <NUM> on the whole while the compactness of the structure is improved.

The refrigerating and freezing apparatus <NUM> may further include a housing <NUM> and a separator. The housing <NUM> may be configured to cover the electromagnetic wave generation module <NUM>, the power supply module <NUM> and the cooling fan <NUM>.

The separator may be disposed in the housing <NUM> and is disposed on a side of the cooling fan <NUM> away from the electromagnetic wave generation module <NUM>, so as to separate a space in the housing <NUM> into an air inlet area and an air outlet area. The cooling fan <NUM> and the electromagnetic wave generation module <NUM> may be disposed in the air outlet area.

<FIG> is a schematic top view of the air outlet area in <FIG>. Referring to <FIG> and <FIG>, the air inlet area and the air outlet area are respectively provided with at least one air inlet <NUM> and at least one air outlet <NUM> in a circumferential direction of the cooling fan <NUM>. At least one air vent <NUM> is formed in a position of the separator corresponding to the at least one cooling fan <NUM>. Thus, the circumstances that water and dust enter the housing <NUM> via the air inlet <NUM> and the air outlet <NUM>, and then the electromagnetic wave generation module <NUM> and the power supply module <NUM> are affected with damp and dust are avoided. Potential safety hazards are also avoided.

The flowing direction of air flow from the at least one air inlet <NUM> to the at least one air vent <NUM> respectively is perpendicular to the flowing direction of air flow from the at least one air vent <NUM> to each air outlet <NUM>, so as to further reduce wind resistance and improve cooling efficiency.

The power supply module <NUM> may be disposed in the air outlet area, and is located on a side of the electromagnetic wave generation module <NUM> perpendicular to the flowing direction of air flow from the at least one air vent <NUM> to each air outlet <NUM>, so that the cooling fan <NUM> cools the power supply module <NUM> and the electromagnetic wave generation module <NUM> respectively in processes of sucking air flow and blowing out the air flow. Influences of heat on the power supply module <NUM> are further reduced. The cooling efficiency is improved.

Further, the refrigerating and freezing apparatus <NUM> further includes a heat conducting material <NUM> thermally connected to the power supply module <NUM> and the separator, so as to improve the cooling efficiency of the power supply module <NUM>.

The electromagnetic wave generation module <NUM>, the power supply module <NUM>, the cooling fan <NUM> and the housing <NUM> may be disposed on the outer side of the heating chamber, so as to reduce influences of heat generated by the electromagnetic wave generation module <NUM> and the power supply module <NUM> on the item to be treated <NUM> in the heating chamber. Further, the electromagnetic wave generation module <NUM> and the like may be disposed on the outer side of the heat insulating layer of the cabinet <NUM>.

The cooling fan <NUM> may be disposed above the electromagnetic wave generation module <NUM>. Namely, the electromagnetic wave generation module <NUM> may be disposed above the heat insulating layer, so as to improve the stability of the electromagnetic wave generation module <NUM> and the cooling fan <NUM>.

The processing unit <NUM> may be configured to acquire a forward power signal output from the electromagnetic wave generation module <NUM> and a reverse power signal returned to the electromagnetic wave generation module <NUM> during working of the electromagnetic wave generation module <NUM>, calculate an electromagnetic wave absorption rate of the item to be treated <NUM> according to the forward power signal and the reverse power signal, and adjust a rotation speed of the cooling fan <NUM> according to the power value of the forward power signal (namely the output power of the electromagnetic wave generation module <NUM>) and the electromagnetic wave absorption rate.

A bidirectional coupler <NUM> may be connected between the electromagnetic wave generation module <NUM> and the radiating antenna <NUM> in series, to monitor the forward power signal output from the electromagnetic wave generation module <NUM> and the reverse power signal returned to the electromagnetic wave generation module <NUM>.

In the present disclosure, the heating unit <NUM> adjusts, according to the power value of the forward power signal output from the electromagnetic wave generation module <NUM> and the electromagnetic wave absorption rate of the item to be treated <NUM>, the rotation speed of the cooling fan <NUM> for cooling the electromagnetic wave generation module <NUM>. Compared to a means of adjusting the rotation speed of the cooling fan <NUM> according to the temperature of the electromagnetic wave generation module <NUM>, there is no need to arrange additional temperature sensing apparatuses, the heat generated by the electromagnetic wave generation module <NUM> can be reflected more precisely, unexpected energy waste and noise pollution are avoided while fully cooling the electromagnetic wave generation module <NUM>, and user experiences are improved.

The processing unit <NUM> is configured to match with the rotation speed of the cooling fan <NUM> on the basis of a preset rotation speed correspondence relation according to the power value of the forward power signal and the electromagnetic wave absorption rate. The rotation speed correspondence relation records rotation speeds corresponding to power values in different ranges and electromagnetic wave absorption rates in different ranges.

Under the condition that the power values of the forward power signal are the same, the rotation speed of the cooling fan <NUM> is in negative correlation with an average value of the electromagnetic wave absorption rates in different ranges; and under the condition that the electromagnetic wave absorption rates are the same, the rotation speed of the cooling fan <NUM> is in positive correlation with an average value of the power values in different ranges, so that the electromagnetic wave generation module <NUM> is cooled efficiently in an energy-saving mode.

The rotation speed correspondence relation may also be a formula which records different power values, electromagnetic wave absorption rates and rotation speeds.

The processing unit <NUM> may also be configured to acquire a temperature of the processing unit <NUM> of the electromagnetic wave generation module <NUM> in real time when the electromagnetic wave generation module <NUM> works, and control the frequency source <NUM> and the power amplifier <NUM> to stop working when the temperature of the processing unit <NUM> is greater than or equal to a preset temperature threshold, so as to guarantee the service life of the processing unit <NUM>.

The processing unit <NUM> may further be configured to control the cooling fan <NUM> to work at a rated rotation speed for a first preset time and then stop working after controlling the frequency source <NUM> and the power amplifier <NUM> to stop working, so as to dissipate heat in the housing <NUM> quickly and avoid heat accumulation.

<FIG> is a schematic flow chart of a control method for the heating unit <NUM> according to an embodiment of the present disclosure. Referring to <FIG>, the control method for the heating unit <NUM> executed by the controller <NUM> of any embodiment mentioned above may include the following steps:.

In the control method of the present disclosure, the rotation speed of the cooling fan <NUM> for cooling the electromagnetic wave generation module <NUM> is adjusted according to the power value of the forward power signal output from the electromagnetic wave generation module <NUM> and the electromagnetic wave absorption rate of the item to be treated <NUM>. Compared to the means of adjusting the rotation speed of the cooling fan <NUM> according to the temperature of the electromagnetic wave generation module <NUM>, there is no need to dispose additional temperature sensing apparatuses, the heat generated by the electromagnetic wave generation module <NUM> can be reflected more precisely, and unexpected energy waste and noise pollution are avoided while fully cooling the electromagnetic wave generation module <NUM>, and user experiences are improved.

Claim 1:
A control method for a heating unit (<NUM>) disposed within a refrigerating and freezing apparatus, the heating unit (<NUM>) comprising a cylinder (<NUM>) configured to contain an item to be treated, and an electromagnetic wave generation system of which at least one part is disposed in the cylinder (<NUM>) or accessed into the cylinder (<NUM>), and the electromagnetic wave generation system comprising an electromagnetic wave generation module (<NUM>) configured to generate an electromagnetic wave signal and a cooling fan (<NUM>) configured to cool the electromagnetic wave generation module (<NUM>), wherein the control method comprises:
acquiring a forward power signal output from the electromagnetic wave generation module (<NUM>) and a reverse power signal returned to the electromagnetic wave generation module (<NUM>);
calculating an electromagnetic wave absorption rate of the item to be treated according to the forward power signal and the reverse power signal; and
adjusting a rotation speed of the cooling fan (<NUM>) according to a power value of the forward power signal, and the electromagnetic wave absorption rate,
wherein the step of adjusting a rotation speed of the cooling fan (<NUM>) according to a power value of the forward power signal, and the electromagnetic wave absorption rate comprises:
matching with the rotation speed of the cooling fan (<NUM>) on the basis of a preset rotation speed correspondence relation according to the power value of the forward power signal, and the electromagnetic wave absorption rate, wherein
the rotation speed correspondence relation records rotation speeds corresponding to power values in different ranges and electromagnetic wave absorption rates in different ranges; and
under the condition that the power values of the forward power signal are the same, the rotation speed of the cooling fan (<NUM>) is in negative correlation with an average value of the electromagnetic wave absorption rates in different ranges; and under the condition that the electromagnetic wave absorption rates are the same, the rotation speed of the cooling fan (<NUM>) is in positive correlation with an average value of the power values in different ranges.