KR100339949B1 - Microwave oven control method and microwave oven for cooking and heating food according to the method and its use - Google Patents

Abstract

A microwave oven control method, a microwave oven, and a method of using the same for automatic cooking and heating of food are disclosed. The control program is selected based on the type of food and the information about the food category information and the food weight for the initial state. The control program is divided into time periods in which the microwave radiation source 20, the microwave active crystal plate 4 and the grill element are activated at the power level determined by the program. The implementation of the program is monitored by determining and decreasing the predicted duration of the time period based on the constant and the food weight determined by the food category (FIG. 1).

Description

Microwave oven control method and microwave oven for cooking and heating food according to the method and its use

The present invention relates to a microwave oven which acts as a separate heating source for food and which can be controlled via a control unit 15 of a microwave oven by means of a microwave oven which is in the form of a recceptacle, To a method for controlling the process for cooking or heating food in a microwave oven using a possible bottom heater (4) and a microwave radiation source (20) of a microwave oven. The present invention also relates to a microwave oven for implementing such a method as well as a method of using such a microwave oven for cooking or heating various types of food by automatically controlled processes.

The microwave radiation source and its associated microwave supply system distribute the microwave into an oven cavity which carries out volume heating of the so-called food.

The microwave oven may have an additional heating source of food in the form of a so-called microwave-activatable crisp or browning plate. Additional heating sources may be provided. The cryp plate may be composed of an aluminum-aluminum plate having a small amount of heat and an excellent thermal conductor provided with a microwave absorbing layer at the bottom.

Swedish Patent Application No. 9003104-8 discloses such a crypt plate. The Browning plate can be composed of a glass or ceramic plate having a larger amount of heat and equipped with a microwave absorbing layer. Generally, the crisp plate and the Browning plate are adapted to rotate during cooking or heating.

The microwave oven may also have another heating source in the form of a so-called grill element or similar IR-radiating element usually mounted on the ceiling of the cavity (see, for example, Swedish Patent Application No. 9201786-2).

Microwave ovens with these three types of heating sources can basically be close to volume heating, floor heating and top heating, in which case the heat release from the two preceding heaters will control the microwave supplied to the cavity , And the top heater is directly controlled with respect to the activation time and power level. To optimize the heating or cooking of certain types of food, the three heating sources must be used in an appropriate manner. That is, it must be activated at the adjusted power levels during the proper period of the cooking or heating process. However, the problem is that the active time and power levels vary greatly for different types of food. For general users, this is too complicated, and therefore there is usually no opportunity for the user to control the cooking or heating process in this way. Instead, the microwave ovens are so configured that there is only one power balance determined by the manufacturer between the other heating sources.

In some countries, the power consumption of a single-phase connection device is limited, which means that the microwave radiation source, and also the grill element, can not be activated simultaneously between different materials. This also places special requirements on the utilization of heating sources depending on the type of food being discussed and tends to complicate matters further for the user.

Accordingly, one object of the present invention is to provide a microwave oven without any of the above-mentioned drawbacks, to favor the utilization of heating sources, and at the same time to provide a more familiar microwave oven.

By optimizing the use of the heating sources, microwave ovens are generally more useful so that the microwave oven can be used in a variety of applications, such as those that must be heated in conventional ovens today to avoid the crispiness of food and cooking And cooking or heating cooks.

According to the invention, this object is achieved by a method of the type mentioned in the opening paragraph, characterized by the following steps.

- providing food category information to the oven for the food,

Selecting a cooking or heating program separated in one or more time periods based on the provided food category information;

- activating the heating sources at power levels according to the selected program for each time period,

Calculating a control variable based on parameter information determined by the food category and one or more parameters obtained from one or more sensors that repeatedly sense the state of the food during each time period;

Decreasing the time periods from the maximum value to zero determined by the food category, after the start of the program,

Ending each time period when the time is reduced to zero or the calculated value of the control variable exceeds a value determined by the food category,

- terminating the program when all time periods have expired.

In preferred modes of implementation of the method of the present invention, the weight information is provided automatically by a weight sensor mounted adjacent to the container, plate or carrier, or manually provided by the user via the control panel of the oven.

The method according to the invention makes handling the microwave oven very convenient. The user should only provide information about the food category, possibly also about the weight, for example via the control panel of the oven. The oven can then be activated automatically or by activating the start button. The oven then selects the titration program according to the food category and fully monitors the cooking or heating process. In the case of conventional ovens, the user did not have to select any power setting and cooking time. Simply, the user can change what he has put in the oven (eg, portions of strongly cooked already cooked chicken) and what the user wants to get out of the oven (eg, portions of the heated chicken that have crusted surfaces) . The oven shows when the dish is ready.

Food and food category information is referred to herein as cooking or heating specially designed for the particular food type, such as potato products, pizza and chicken, and the state of the food in the oven, such as fresh or unfrozen frozen products and semi-processed frozen products Means information corresponding to the program.

The food category information may be provided by entering a numerical value indicating the type of food and its state, or by entering a first value indicating the type of food and a second value indicating its initial state. Food category information is also entered by operating a specific control button for the food category or by operating specific buttons for the type of food and its initial state.

The microwave oven according to the present invention comprises a cavity, a microwave radiation source for supplying microwaves to the cavity, a microwave activatable bottom heater in the form of a container, plate or carrier for containing the food to be heated or cooked, Wherein the oven has means for providing to the control unit information about the food weight and means for providing food category information for the food to the control unit, The microprocessor of the control unit is programmed to implement the following functions.

- selecting a cooking or heating program separated into one or more time periods based on the provided food category information,

- calculating the predicted duration of each time period based on the weight information (w) as well as parameter information determined by the food category;

- activating the microwave radiation source and the bottom heater during power levels and activation times according to the selected program,

After starting the program, decreasing the time periods from the calculated value to zero;

The ability to terminate each time period when the time period has been reduced to zero and

And terminating the program when all time periods have expired.

In a preferred embodiment of the present invention, the microwave oven is equipped with a top heater, for example a grill element located in the ceiling of the cavity, which is controlled by the selected program.

In another embodiment of the microwave oven according to the present invention, the weight sensor is adapted to be placed adjacent to the container, plate, or carrier and to automatically provide information about the weight of the food. In another embodiment, the control panel of the oven has means for manually providing information about the weight of the food.

The design of the microwave oven of the present invention is based on the fact that most general users use an oven to cook or heat some type of food, for example already cooked frozen food or bread and potato products, And its initial state, and that the combined information on the food category and the weight of the food is determined by the food category and is adaptable to the program automatically implemented by the oven . In addition, optimal utilization of the heating sources available in modern ovens (i.e., microwave fields in the cavity, floor heating crysplak plates, top heating grill elements) can be realized to improve the results of cooking, So that the user's intimacy with the oven is maintained or improved.

In accordance with the present invention, the use of a microwave oven with a grill element oven mounted on the ceiling of an oven cavity and a rotating crisscross plate mounted in an oven cavity allows the cooking or heating of the food to be effected by the type of food provided in the oven and its initial state And is automatically performed according to programmed cooking or heating programs that can be selected based on information about the food-category-based information and the weight of the food.

More specific aspects of the microwave oven and method thereof according to the present invention are described in the appended claims.

The invention will be described in more detail below with reference to the preferred and non-limiting embodiments shown in the drawings.

The microwave oven described in FIG. 1 has an outer case 1, an oven door 2 for closing the cavity, and a crystal plate 4 provided in the microwave oven. The crypt plate 4 is made of an aluminum sheet having a small calorie content, and a microwave absorbing layer of rubber ferrite is provided on the bottom surface. Preferably, the ferritic material used has a Curie point that stops absorption of energy from the microwaves, which means that the top surface temperature of the crystal plate in contact with the food is stabilized within a temperature range of 130 to 230 ° C. The crypt plate is rotated during the cooking or heating process. In addition to Applicant's microwave ovens VIP20 and VIP27 versions, Swedish Patent Application No. 9003104-8 describes a more detailed structure as well as the rotation mechanism of the crypt plate.

The microwaves are input into the cavity 3 through one or more supply apertures 0 (not shown) connected to the microwave radiation source 20 (typically a magnetron) of the oven (see FIG. 2) through the waveguides. In the oven described, a magnetron, an associated waveguide system, a power unit 19 for operating the magnetron, and a control unit 15 are arranged behind the control panel 5. In a preferred embodiment of the microwave supply system, the use of the system with the upper and lower feed openings provided in the right sidewall of the cavity is made, while the remainder of the feed system is designed to feed the polarized microwaves through these openings . For more detailed information on the structure of the microwave supply system, reference is made not only to the applicant's microwave ovens mentioned above, but also to the Swedish patent 9003012-3.

A grill element (not shown) is mounted on the ceiling of the cavity in the manner described, for example, in Swedish Patent Application No. 9201786-2. The grill element may be a so-called " grill tube ", a quartz tube or a halogen radiation source. Examples of specific designs are found in the Applicant's VIP20 type microwave oven.

The control panel 5 has a display 6 which is controlled by a control unit 15 which displays plain-text messages or symbols for the selected program, the remaining cooking or heating time . That is, information on how cooking or heating is proceeding, and user choices made through the control panel.

The control button 7 is used to select heating through the supply of microwaves to the cavity. The button 8 is used to activate the grill element of the oven, and the time required is set by the knob 9. These basic options are the same as those of conventional ovens and allow the user to select from pre-programmed cooking or heating programs for a certain number of specific types of food while utilizing the interaction of the microwave directly acting on the crystal plate and grill element An option of the present invention is added. If the heating process includes only microwaves directly acting on the food, the removable cryp plate may be replaced by a general rotating bottom plate. When selecting preprogrammed programs, the knob 9 is also used to manually input the food weight.

The buttons 10 and 11 are each adapted to start and switch off the oven. A key set 12 is used to enter food category information and select a programmed cooking or heating program. For example, the buttons may be from top to bottom, a heating button of a frozen pizza, a heating button of a frozen pie, a heating button of a frozen potato product such as a chip, and a heating button of portions of a frozen chicken. The operation of the button requires simultaneous entry of complete food category information, that is, information about the type of food and its initial state (e.g., frozen state). In a modified embodiment of the oven, the buttons are separated into two sets, in which information about the type of food is entered via a set of buttons and information about the initial state of the food is entered via another set of buttons. In the simplest embodiment of the oven, only one food category is used, which means that only one button is required. All the buttons, as well as the knobs and the display, are connected to the control unit 15. The upper surface of the oven is provided with ventilation holes 13 connected to an exhaust channel (not shown) of the cavity, and a space exists between the ceiling of the cavity and the outer case 1 in the cavity. In the single phase connection with the mains, the oven has a cord 14 with a plug.

The block diagram of FIG. 2 shows the control unit 15 and the microprocessor and its associated program memory 16. User information is input to the control unit via block 17, which represents the control buttons and knobs described above. The control unit controls the display (6). The control unit 15 controls the microwave radiation source 20 through the driver 18 and the microwave power supply unit 19 to control the supply of the microwave to the cavity 3. [ Through the driver 21, the control unit 15 controls the grill element 22, and the IR radiation is supplied to the cavity 3. The information from the cavity is transmitted to the control unit 15 via the humidity sensor 23 and the temperature sensor 24, which sense the humidity and temperature of the air, respectively, with respect to the ventilation air in the exhaust channel of the cavity. Thus, the control of the cooking or heating process is carried out by the complete feedback, minimizing the sensitivity, starting temperature, and mains voltage of the cooking or heating process for changes in the raw food product food. For more detailed information on these unit structures, reference is made to the above-mentioned patents as well as the Makpak < RTI ID = 0.0 > Popa oven < / RTI >

Alternatively, the weight information is automatically provided to the control unit by the weight sensor 23 (indicated by the dashed line). The weight sensor 23 is disposed adjacent to the crypt plate 4 and senses the weight of the food placed on the crypt plate. For example, the weight sensor may be the design described in Swedish Patent Application No. 9300291-3.

In the third figure, the flow chart describing the preprogrammed cooking or heating program consists of three successive time periods T1, T2, and T3. In each cycle, the expected durations T1e, T2e, T3e are calculated based on the food weight w determined by the food category and the constants k1, k2, k3, respectively, according to the following equation:

T1e = k1 ˚w

T2e = k2 ˚w

T3e = k3 ˚w

During each cycle, microwaves are fed, and the grill element as well as the crysophanis are activated to power levels determined by the food curry ring. The power levels for the microwave and grill elements, respectively, during the associated periods are designated PM1, PM2, PM3 and PG1, PG2, PG3, respectively. These power levels are optimized for each food category and may change during those time periods in another improved oven. The constants k1, k2, k3 are optimized for each food curry. In yet another improved oven, the supplied microwave power may be distributed among other supply openings to distribute energy between the bottom heating of the crystal plate and the microwave heating inside the food. Such a distribution can be realized using a microwave input system of the kind described in Swedish Patent No. 9302302-6.

The program described in the flowchart of FIG. 3 performs the following steps, where Y represents "Yes" and N represents "No".

S1. start

S2. Detect net weight w of food

S3. Tle, T2e, and T3e respectively

S4. Power PM1 of the microwave, cooked at the power PG1 of the grill element and decreased T1e

S5. If Tle = 0 ?, Y proceeds to S6, and if N, returns to S4

S6. Microwave power PM2, grill element power PG2 and reduced T2e

S7 T2e = 0? If Y, proceed to S8; if N, return to S6

Q8. Microwave power PM3, cooked at power PG3 of the grill device and reduced T3e

S9 T3e = 0 ?, if Y, proceed to S10; if N, return to S8

S10. End of program

For example, the temperature of the ventilation air can be sensed by a temperature sensor installed in the exhaust channel of the cavity. The compensation calibration is selected through the food category and consists of selected constants that are used to calculate the predicted duration of the program time period based on the sensed initial temperature. Thus, any influence of the oven being heated even in the start step is removed. Another improvement is to provide the control unit with information about the temperature of the crysplan plate as another control parameter.

When implementing the method according to the present invention, so-called fuzzy logic judgment can be applied. Any modifications derived therefrom may be accomplished only within the scope of the appended claims.

FIG. 1 is a view of a microwave oven of the present invention with a door open; FIG.

FIG. 2 is a block diagram illustrating the supported functional units of an oven while implementing the improved method. FIG.

3 is a flow chart illustrating a cooking or heating program programmed to control the microprocessor of the control unit;

[Description of Reference Numerals]

3: cavity 5: control panel

7: Control button

Claims (15)

A microwave activatable floor heater 4 in the form of a container, plate or carrier which serves as separate heating sources for the food and in which controllable food is placed via the control unit 15 of the microwave oven, A method of controlling a process for cooking or heating food in a microwave oven using a source (20) - providing food category information for the food to the oven, - providing information about the weight (w) of the food, Selecting a cooking or heating program separated in one or more time periods based on the provided food category information; Calculating predicted durations (T1e, T2e, ...) of each time period based on the weight information as well as the parameter information (k1, k2, ...) determined by the food category; Activating the heating sources at power levels according to the selected program and during an activation time for each time period, Decreasing the time periods from the calculated value (T1e, T2e, ...) to zero after the start of the program, Terminating each cycle when the time period has been reduced to zero, and terminating the program when all time periods have expired. The method according to claim 1, The microwave oven further comprises an upper heater in the form of a grill element or some other equivalent electrical IR radiating element as an additional controllable heating source and further comprising activating the upper heater in accordance with the selected program Lt; / RTI > The method according to claim 1, The microwave oven includes a weight sensor (23) disposed adjacent to the container, plate, or carrier, wherein providing information about the weight of the food comprises, when starting the cooking or heating program, Is performed automatically. The method according to claim 1, The microwave oven has a control panel equipped with means (9) for inputting information about the weight of the food, Wherein the step of inputting information on the weight of the food is performed manually by the operator via said means before starting said cooking or heating program. The method according to claim 1, The program is divided into time periods (T1, T2, ..., Tn) having associated constants (kl, k2, ..., kn) The step of calculating the predicted durations (Tle, T2e, ..., Tne) of each time period T1e = kl ˚ w T2e = k2 ˚w ... Tne = kn ˚w (W) < / RTI > A cavity 3, A microwave radiation source 20 for supplying microwaves to the cavity, A microwave activatable floor heater 4 in the form of a container, plate or carrier in which food to be heated or cooked is placed, A microwave oven comprising a control unit (15) for controlling the bottom heater as well as supplying microwaves to the cavity, Means (9) for providing the control unit with information about the weight of the food, And means (12) for providing food category information for the food to the control unit, The microprocessor (16) of the control unit Selecting a cooking or heating program separated into one or more time periods (T1, T2, ...) based on the provided food category information, Calculating the predicted duration T1e, T2e, ... of each time period based on the weight information w as well as parameter information (k1, k2, ...) determined by the food category; Activating the microwave radiation source (20) and the bottom heater (4) during power levels and activation times in accordance with the selected program; Decreasing the time periods from the calculated value (T1e, T2e, ...) to zero after starting the program, A function of terminating each time period when the time period is reduced to zero, Programmed to implement the function of terminating the program when all time periods have expired. The method according to claim 6, The means for providing the control unit 15 with information about the weight w of the food comprises a weight sensor (not shown) disposed adjacent to the container, plate or carrier for automatically sensing the weight of the food when the program is started 23). ≪ Desc / Clms Page number 13 > The method according to claim 6, Characterized in that the means for providing information on the food weight to the control unit (15) comprises means adapted to form a part of the control panel (5) of the oven and for manual input of the weight of the food Microwave oven. 9. The method of claim 8, Wherein said input means is in the form of a knob (9) and is also used to set a predetermined cooking or heating time when said preprogrammed programs are not used. The method according to claim 6, Means for providing food category information for said food to said control unit (15) is devised as operating means for providing a parameter, said parameter being based on the type of food and its initial state and for cooking or heating Wherein the microwave oven corresponds to a program. The method according to claim 6, The means for providing food category information for the food to the control unit (15) is devised as a first means for providing a food type parameter and a second means for providing a food status parameter, Wherein the microwave oven corresponds to a cooking or heating program stored in the unit. The method according to claim 6, Characterized in that it comprises a control panel (5) equipped with a display (6) for displaying a designation, symbol or plain-text message indicating the selected cooking or heating program. The method according to claim 6, And a top heater in the form of a grill element or some other equivalent electrical IR radiating element that can be controlled via the control unit in terms of active time and heating power according to the selected program. The method according to claim 6, And a microwave absorbing layer disposed on the bottom surface of the crystal plate, wherein the grill element is mounted on the ceiling of the cavity, and the oven comprises a crucible plate (4) made of a metal having a small calorie content, Wherein the E-vector or H-vector of the polarized microwave has a feed opening on any level of the microwave absorbing layer and is adapted to supply polarized microwaves, wherein the E-vector or H-vector of the polarized microwave extends substantially in the plane of the microwave absorbing layer Features microwave oven. 1. A method of using a microwave oven having a crystal plate (4) for rotation and microwave absorption, as well as a grill element mounted on the ceiling of an oven cavity (3) Used to automatically cook or heat food according to preprogrammed cooking or heating programs that can be selected based on information about the weight of the food as well as food category information about the type of food served to the oven and its initial state Microwave oven.