JPH0139640B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a thawing cooking method using a high-frequency heating device, and particularly to one configured to automatically perform thawing and cooking sequentially.

Configuration of conventional examples and their problems Thawing of frozen foods by microwave heating is completed in an extremely short time, resulting in good quality after thawing, and has been put into practical use more widely than ever before. Here, we will refer to the so-called thawing cooking method, which involves heating frozen cooked foods and frozen vegetables such as Mitsu Vegetables all at once after thawing them.
Conventionally, such defrosting cooking methods generally involve heating at a constant power from defrosting to cooking. It then uses an infrared sensor to detect when the food is heated and automatically finishes cooking. This traditional thawing cooking method requires a short heating time, but on the other hand, it tends to cause cold spots in the center of the food, which are unthawed parts.
There was a problem in that homogeneity was impaired between areas where melting started earlier and areas where melting slowed, resulting in a mushy finish even though there was no difference in temperature.

OBJECTS OF THE INVENTION The present invention solves the above-mentioned conventional drawbacks, and aims to provide a heating pattern that can reduce temperature differences in food during thawing and cooking and improve homogeneity.

Configuration of the Invention In order to achieve the above object, the high frequency heating device of the present invention includes a weight sensor that detects the weight of frozen food;
Equipped with a non-contact temperature sensor such as an infrared sensor that detects the surface temperature of the heated object, the frozen food is first heated at high output until the surface temperature detected by the non-contact temperature sensor reaches a predetermined value, and then heated by a weight sensor. The food is thawed at low power for a time calculated based on the detected weight of the food, and then automatically cooked using a non-contact temperature sensor.The food is thawed automatically for a time calculated based on the weight of the food, and then automatically cooked using a non-contact temperature sensor. realizable.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on the drawings.

FIG. 1 is a perspective view of a high-frequency heating device according to the present invention. A door body 2 is pivotally supported on the front surface of the main body 1 so as to be freely openable and closable, and an operation panel 3 is arranged. An auto key is provided on the operation panel 3, and a thawing/cooking key 4 according to the present invention is provided therein.

FIG. 2 is a block diagram showing one embodiment of the configuration of the present invention. Commands input from the thawing/cooking key 4 on the operation panel 3 are decoded by the control section 5. Then, the control unit 5 starts defrosting and cooking the frozen food, which is the object to be heated 7 placed in the heating chamber 6 . The heating is controlled by being supplied with power via a driver 8 to a magnetron serving as high frequency generating means 9.

For heating, thawing is first performed by sequentially changing the output, and then cooking is performed using high output. Thawing is time-controlled based on the weight of the frozen food 7 on the mounting tray 11 detected by the weight sensor 10, using a non-contact temperature sensor 12 in combination.
This is because the non-contact temperature sensor 12 can only detect the surface temperature of the food, so it cannot eliminate the temperature difference between the surface and the center, leaving a cold spot in the center, especially in thick foods. Since this was unavoidable, this problem will be improved using weight data. In other words, the temperature difference between the surface and the center is estimated based on the weight of the food, and the time from when the surface reaches a certain temperature until the center has fully thawed is controlled. This is because the dielectric loss of frozen food is constant regardless of the material, meaning that meat and vegetables of the same weight can be thawed in the same amount of time. Furthermore, by heating the surface until it reaches a certain temperature before shifting to time control, differences in freezing temperatures can also be resolved.

When thawing by weight is completed, the microwave is then switched to high output and the cooking begins. Once thawed, time control is no longer possible as the dielectric loss of the food differs depending on the material. In other words, even if meat and vegetables have the same weight, the cooking time is very different, and cooking time cannot be determined based on weight, as is the case with thawing. Therefore, cooking is automatically performed using the non-contact temperature sensor 12. The non-contact temperature sensor 12 detects the point in time when the surface temperature of the food reaches a predetermined temperature, and controls the point in time when cooking is completed.

Note that the weight sensor 10 may employ a capacitance method or a strain gauge method to detect the amount of displacement of the mounting plate 11, or a vibration method that measures a fixed frequency. In addition, as the non-contact temperature sensor 12, a pyroelectric infrared sensor and a SAW using surface acoustic waves are used.
Sensors are available. 13 is a detection circuit for these sensors; 14 is a motor that rotates the mounting plate 11 to improve uneven heating; and 15 is a cooling fan.

FIG. 3 is a heating pattern for thawing cooking showing an embodiment of the present invention. Diagram a shows the microwave output, and diagram b shows the temperature rise of the food. Heating is done in defrosting mode “DEF” and cooking mode “COOK”
The decompression mode is further divided into three small modes. First, _T1 ends when the microwave is heated at full power and the surface temperature () reaches a predetermined value A. In this mode, the temperature of the frozen food is raised all at once, and before the surface starts to boil, it is transferred to the next T ₂ mode.
In other words, it shifts to sleep mode. _T2 time is _T1
T ₂ =K ₂ T ₁ (K ₂ : constant) is calculated based on the time, and carryover heating is performed during this time to eliminate temperature unevenness. () in figure b is the temperature at the center of the food, but the center is difficult to thaw, and even if the surface () rises to A °C in _T1 mode, the center still remains ice. Therefore, in T ₂ mode, the surface temperature drops again and begins to freeze. This is the role of _T2 mode. In addition to this, the T ₂ time may be determined by using a non-contact temperature sensor to detect the point at which the surface temperature returns to a certain temperature, for example 0°C, and from the weight of the food, T ₂ = K ₂ ′W (K ₂ ′: (constant).

The following T ₃ mode is a mode in which the power is reduced to prevent the surface from boiling while thawing the center of the food, and the time is calculated by T ₃ = K ₃ W (K ₃ : constant). In other words, the time is controlled based on the weight detected by the weight sensor.

Once defrosting is completed through these steps, the next step is to move to the cooking mode "COOK". Here, the time required for the surface temperature of the food to reach the predetermined temperature B is t ₄
is counted, and based on this, T ₄ =t ₄ +Kt ₄ (K: constant) is calculated. K may be zero.

As described above, the thawing cooking of the present invention uses a weight sensor and a non-contact temperature sensor to effectively automatically heat food in two modes: thawing and cooking.

Effects of the Invention As described above, according to the present invention, the following effects can be obtained.

(1) Allows for thawing cooking with small temperature differences without localized boiling or cold spots in the middle.

(2) At the end of thawing mode, there is little difference in the degree of melting of each part, and subsequent cooking can be thawed without compromising homogeneity and without becoming mushy.

(3) Using a weight sensor and a non-contact temperature sensor,
You can defrost and cook automatically.

(4) At the beginning of thawing mode, a non-contact temperature sensor is used to raise the surface temperature of the food to a constant value, so even if the frozen temperature is different or it has been a long time since the food was taken out of the freezer, it can be corrected during _T1 mode. , and there is little variation in the degree of thawing.

[Brief explanation of drawings]

FIG. 1 is a perspective view of the main body of a high-frequency heating device showing one embodiment of the present invention, FIG. 2 is a block diagram showing the same configuration, and FIGS. 3a and 3b are diagrams showing the same heating pattern. 4... Thawing cooking key, 5... Control unit, 6... Heating chamber, 7... Item to be heated, 9... High frequency generation means,
10... Weight sensor, 12... Non-contact temperature sensor.

Claims (1)

[Claims] 1. A heating chamber for accommodating an object to be heated, a high frequency generating means coupled to this heating chamber, a control section for controlling power supply to this high frequency generating means, a weight sensor for detecting the weight of the object to be heated, and a It consists of a non-contact temperature sensor that detects the surface temperature of the heated object and a key that commands defrosting and cooking, and when heating is commanded by the key, the control section starts supplying power to the high frequency generating means, and The non-contact temperature sensor detects the surface temperature of the heated object, and when it reaches a certain predetermined temperature, the power supply to the high frequency generating means is controlled to reduce the output, and the heated object detected using the weight sensor thawing is continued at a low output for a time calculated based on the weight of the food, then the power supply to the high frequency generating means is switched to a higher power to perform cooking, and the end of cooking is controlled by the non-contact temperature sensor. A high-frequency heating device configured as follows.