JPH07269868A - Heating and cooking device - Google Patents

Abstract

PURPOSE:To realize a heating and cooking device capable of performing a high accurate defrosting and heating operation. CONSTITUTION:A required heating time determined in response to information about a dielectric loss of food detected by an electrical field intensity sensor 7 at the beginning of starting a heating operation and information about an amount of food detected by a weight sensor is revised at a predetermined time before finishing of the predetermined heating time and corrected in response to information about the dielectric loss of the food redetected through the electrical field intensity sensor 7, thereby it becomes possible to calculate the most suitable heating time under application of an influence of hot air energy added in the midway of the operation. Then, since the heating operation is performed on the basis of the most suitable heating time calculated in this way, the high accurate defrosting and heating control not found in the prior art is realized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating cooker for thawing frozen food by utilizing high frequency energy and hot air energy.

[0002]

2. Description of the Related Art Conventionally, a cooking device for thawing and heating frozen foods is one in which heating is stopped when a thawing state is reached by manually setting a heating time according to the weight of the frozen foods. A weight sensor is provided on the structure that supports the table, the weight information obtained from it is processed into heating time information required by a control circuit such as a microcomputer, and heating is automatically controlled based on the time information. A modification of the automatic control method that automatically controls the heating output according to the weight to be measured, as well as the direction of reflection of the high-frequency energy transmitted in the waveguide during heating. Focusing on changes in the levels of components, and controlling heating by judging that thawing has been completed when the changes have reached a predetermined change (Japanese Patent Laid-Open No. 5-41287) (See the report) etc. have been put to practical use.

Among them, the one that controls the heating by paying attention to the change in the level of the reflection direction component of the high frequency energy transmitted in the waveguide has extremely high control accuracy as compared with other control examples. Although it has its characteristics, it has a drawback that it cannot escape from the trouble caused by the use of high-frequency energy that the overheating phenomenon easily occurs in the corners and thin portions of food.

Attempts have also been made to promote uniform heating so as not to damage the food even when there is a difference in the shape of the food. That is, the outside air is supplied to the heating chamber during thawing and heating to cool the surface of the food so that boiling does not occur on the surface of the food (JP-A-5-10188).
(See Japanese Patent Publication No. 1).

[0005]

In the case where cold air is supplied into the heating chamber during heating to prevent overheating of the food surface, although some effect is obtained for overheating the surface, In addition to being affected by the temperature of cold air, the fact is that it has little effect on overheating the inside of food.

In the control focusing on the level change of the reflected energy in the high frequency energy transmitted in the waveguide, the relationship between the weight of the frozen food and the time required for the predetermined change in the reflected energy occurs. Based on that, it is possible to determine at what temperature the frozen food was stored below freezing, but if uneven heating occurs, the level of reflected energy may change rapidly, so In such a case, there is a problem that it becomes difficult to predict the frozen storage temperature with high accuracy and control the thaw heating with high accuracy based on the prediction.

To cope with this difficulty, it was not useful to supply cold air into the heating chamber as described above.

[0008]

In order to solve the above-mentioned problems, the present invention provides a heating chamber for storing frozen foods, a high-frequency generating means for supplying high-frequency energy into the heating chamber, and hot air in the heating chamber. Hot air generating means for supplying, dielectric loss detecting means for detecting dielectric loss of frozen food stored in the heating chamber, weight detecting means for detecting weight of frozen food stored in the heating chamber, and heating chamber The outside temperature detecting means for detecting the outside temperature, and the dielectric loss information of the frozen food detected by the dielectric loss detecting means when the operation of the high frequency generating means and the hot air generating means are started, and the weight detecting means are detected. The information about the amount of frozen food to be taken in is taken in to determine the first required heating time for thawing the frozen food, and the operation of the high frequency generating means and the hot air generating means is continued and The frozen food detected by the dielectric loss detection means at a predetermined point in time during which the first required heating time elapses, in addition to taking in information on the heat / heat outside temperature detected by the temperature detection means and controlling the hot air generation means. The second required heating time is determined by correcting the first required heating time already determined by re-acquiring the information about the dielectric loss of The heating cooker is constituted by the means and the control means for controlling so as to stop the operation of the hot air generating means.

Further, the control means, when the information about the dielectric loss of the frozen food which is detected by the dielectric loss detecting means at that time is fetched again at a predetermined time during the elapse of the first required heating time. The first required heating time and the first high-frequency heating output of the high-frequency generating means, which have already been determined, are respectively corrected to determine the second required heating time and the second high-frequency heating output, and the second high-frequency heating is performed. The operation of the high frequency generating means and the hot air generating means is stopped when the second heating time by the heating output has elapsed.

Further, regarding the control means, when the information about the dielectric loss of the frozen food detected by the dielectric loss detecting means at that time is fetched again at a predetermined time during the elapse of the first required heating time. When the value of the dielectric loss reaches a predetermined value, the operation of the high frequency generating means and the hot air generating means is stopped.

[0011]

When the operation of the high frequency generating means and the hot air generating means is started, the control means measures the dielectric loss of the frozen food, which is the object to be heated, through the dielectric loss detecting means, and takes in the information. At the same time, the weight of the frozen food is measured by the weight detecting means, and information regarding the amount of the frozen food is taken in. At that time, the information about the heating outside temperature is also taken in through the heating outside temperature detecting means, the first required heating time expected to be necessary for thawing the frozen food is determined, and the heating operation is continued while controlling the hot air generating means. . Then, at a predetermined time point during the elapse of the first required heating time which is determined and executed, the information about the temperature of the frozen food which is in the process of rising in temperature is re-acquired through the dielectric loss detection means, and the already-executed first The one required heating time is corrected to determine the second required heating time, and when the corrected second required heating time elapses, the control of the high frequency generating means and the hot air generating means is stopped.

[0012] Further, when the control means fetches again the information regarding the dielectric loss of the frozen food detected by the dielectric loss detection means at that time at a predetermined time during the elapse of the first required heating time, The second required heating time and the second high frequency heating output are determined by correcting the already determined first required heating time and the first high frequency heating output of the high frequency generator, respectively, and the second high frequency heating output is determined. When the second heating time by the output has elapsed, the operation of the high frequency generating means and the hot air generating means is controlled to stop.

Further, when the control means fetches the information about the dielectric loss of the frozen food detected by the dielectric loss detecting means at that time at a predetermined time during the elapse of the first required heating time, When the value of the dielectric loss has reached a predetermined value, control is also performed so as to stop the operation of the high frequency generating means and the hot air generating means.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

In FIG. 1, 1 is a heating chamber, and 2 is a frozen food contained in the heating chamber 1. 3 is a magnetron for supplying high-frequency energy into the heating chamber 1, and 4 is a hot air generator for supplying hot air into the heating chamber 1. The hot air generator 4 is composed of an electric heater 5 such as a sheath heater and a radial fan 6. Reference numeral 7 is a sensor that outputs information regarding the dielectric loss of food, and here, an electric field intensity sensor that detects the energy intensity of the high frequency energy supplied from the magnetron in the heating chamber 1 is used. This electric field strength sensor 7
Focusing on the fact that the high-frequency energy intensity in the heating chamber 1 relatively decreases in order to increase the absorption amount of the high-frequency energy in the heating chamber as the dielectric loss of food increases with the temperature rise. It is used to estimate the temperature of frozen food itself from the decrease rate of electric field strength with respect to time and the information on the weight of food output from the weight sensor described later. It is used to estimate the degree of increase in loss) and whether or not a thawed state has been reached. When the frozen food is in a thawed state, the dielectric loss of the food becomes maximum and the electric field strength detected by the electric field strength sensor 7 becomes minimum. Reference numeral 8 denotes a heating-room temperature sensor that detects the temperature outside the heating chamber 1, and detects the temperature of the room in which the cooking device is installed. 9 is a turntable on which frozen foods are placed, and 1
0 is an electric motor that drives the turntable 9 to rotate, 11
Is a weight sensor for detecting the weight of the frozen food placed on the turntable 9. 12 is a control device, which includes an electric field strength sensor 7, a heating chamber outside temperature sensor 8,
The information of the weight sensor 11 is taken in to perform information processing, and the operations of the hot air generator 4, the magnetron 3, and the turntable driving electric motor 10 are controlled.

Next, the operation of the embodiment thus configured will be described.

When the frozen food 2 such as tuna sashimi is placed on the turntable 9 in the heating chamber 1 and the controller 12 is instructed to start the heating operation, the controller 12 starts the operation of the magnetron 3. At the same time, measurement of the electric field intensity in the heating chamber 1 and the weight of the frozen food 2 is started through the electric field intensity sensor 7 and the weight sensor 11. Controller 12
Is the temperature of the sashimi material (for example, whether it has been frozen at minus 20 ° C. or minus if the rate of change of the electric field strength within a predetermined time is taken into consideration and the information obtained from the weight sensor 11 is added. It was stored at 5 ° C), and the high-frequency output and the required heating time estimated to thaw the sashimi material of that temperature and weight were determined, and the timer function in the controller 12 The required heating time is set, and the driving of the magnetron 3 is continued during that time. At that time, the output of the magnetron 3 is appropriately adjusted by gradually reducing it according to the lapse of operating time, and the output of the magnetron 3 is devised so as to suppress uneven heating as much as possible. At the same time, the information from the heating-room temperature sensor 8 is taken in,
The drive control of the hot air generator 4 according to the temperature outside the heating chamber is started. That is, heating with hot air energy is performed in addition to heating with high-frequency energy, and the advantages of each heating are maximized.

By the way, not only high-frequency energy but also hot air energy is added to the actual heating operation, and the amount of hot air energy is adjusted according to the temperature outside the heating chamber. Needless to say, the required heating time determined based on the information of the weight sensor 11 needs to be corrected.

In this embodiment, the electric field in the heating chamber 1 is again passed through the electric field intensity sensor 7 at a predetermined time before the required heating time determined at the beginning of heating is finished, for example, 10% before the total required heating time. The strength is detected and the degree of temperature rise of the food is checked.If it is determined from the result of the check that the required heating time initially set needs to be increased or decreased, the initial required heating time is corrected to an optimum value. Control to continue heating.

As described above, the required heating time determined in advance on the basis of the information on the dielectric loss of the food detected by the electric field strength sensor 7 at the start of heating and the information on the amount of the food detected by the weight sensor 11 Since the correction is made based on the information on the actual dielectric loss of the food measured through the electric field strength sensor 7 at a predetermined time point before the end, it is possible to perform the thawing heating just enough.

Further, the hot air generator 4 for supplying hot air into the heating chamber 1 is controlled according to the output value of the temperature sensor 8 outside the heating chamber. It was possible to be free from the influence of the dispersion of the detected values due to the temperature unevenness of.

In the above description, an example in which the required heating time is corrected based on the value detected by the electric field strength sensor 7 during the heating operation has been taken up. However, not only the time value but also the high frequency output of the magnetron 3 is corrected. It is also meaningful to do.

Furthermore, during heating, the electric field strength sensor 7
Needless to say, it is preferable to immediately stop the operation of the high-frequency generating means and the hot air generating means when the value detected by has already reached the predetermined region.

[0024]

As described above, according to the present invention, the required heating time determined on the basis of the information of the food weight detecting means and the means for detecting the dielectric loss of food such as the electric field strength sensor at the beginning of heating. , Was corrected based on the information about the dielectric loss of the food that is detected by the dielectric loss detecting means again at a predetermined time before the end of the required heating time, and the effect of hot air energy added in the middle was added. It has become possible to find a more optimal heating time. Since the heating operation is executed based on the obtained optimum heating time, the defrosting heating control with higher accuracy than ever has been realized.

Further, the hot air generating means for supplying hot air into the heating chamber may be simply controlled according to the temperature outside the heating chamber, so that the temperature inside the heating chamber is detected by detecting the temperature inside the heating chamber. It was released from the influence of variations in the detected values due to the temperature unevenness in the heating chamber.

[Brief description of drawings]

FIG. 1 is a plan sectional view of a heating cooker showing an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view of a heating cooker showing an embodiment of the present invention.

[Explanation of symbols]

 1 Heating Chamber 2 Frozen Foods 3 Magnetron 4 Hot Air Generator 5 Electric Heater 6 Radial Fan 7 Electric Field Strength Sensor 8 Heating Room Outside Temperature Sensor 9 Turntable 10 Electric Motor 11 Weight Sensor 12 Controller

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yukitoshi Sugaya 1-3, Shinjuyoji, Kashiwa City, Chiba Prefecture

Claims (3)

[Claims] 1. A heating chamber (1) for storing frozen food, a high frequency generator (3) for supplying high frequency energy into the heating chamber, and a hot air generator (4) for supplying hot air into the heating chamber. A dielectric loss detecting means (7) for detecting a dielectric loss of the frozen food contained in the heating chamber, a weight detecting means (11) for detecting a weight of the frozen food contained in the heating chamber; Heating outdoor temperature detecting means (8) for detecting the temperature outside the room, and dielectric loss of frozen food detected by the dielectric loss detecting means when the operation of the high frequency generating means and the hot air generating means is started. Information regarding the amount of frozen food detected by the weight detection means and the first required heating time for thawing the frozen food is determined to continue the operation of the high frequency generation means and the hot air generation means. In addition to controlling the hot air generating means by taking in information on the heating chamber outside temperature detected by the heating outside temperature detecting means, the dielectric loss at that time at a predetermined time during the passage of the first required heating time. By re-acquiring the information about the dielectric loss of the frozen food detected by the detection means, the first required heating time which has already been determined is corrected to determine the second required heating time, and the second required heating is performed. A heating cooker comprising a high frequency generating means and a control means (12) for controlling to stop the operation of the hot air generating means when time has elapsed. 2. The control means, at a predetermined time point during the elapse of the first required heating time, reacquires the information about the dielectric loss of the frozen food detected by the dielectric loss detection means at that time point. At this time, the second required heating time and the second high-frequency heating output are determined by correcting the already-determined first required heating time and the first high-frequency heating output of the high-frequency generating means, respectively. 2. The cooking device according to claim 1, wherein the heating cooker is controlled so as to stop the operation of the high frequency generating means and the hot air generating means when the second heating time by the second high frequency heating output has elapsed. . 3. The control means reacquires, at a predetermined time point during the elapse of the first required heating time, information regarding the dielectric loss of the frozen food detected by the dielectric loss detection means at that time point. At this time, when the value of the dielectric loss has reached a predetermined value, control is performed so as to stop the operation of the high frequency generating means and the hot air generating means. The cooker described.