JPS60258894A - High frequency heater - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

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

Structure of conventional example and its problems Defrosting of frozen foods by microwave heating is completed in an extremely short time, resulting in good quality after thawing, and has been widely used in practical use. Here you can find frozen cooked foods and frozen vegetables such as Minox Becitapul.
After thawing - I will mention the so-called thawing cooking method, which involves heating the food.

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 conventional thawing cooking method requires a short heating time, but on the other hand, cold spots tend to appear in the center of the food, and uniformity is lost between areas that start melting early and areas that melt slowly, resulting in temperature fluctuations. Even if there was no difference in the results, the problem was that the results were sloppy.

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

Structure 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 and a non-contact temperature sensor such as an infrared sensor that detects the surface temperature of the object to be heated. The structure is such that the frozen food is thawed by weight and then automatically cooked using a non-contact temperature sensor, and the temperature difference after thawing and cooking is small, and automatic thawing and cooking with excellent homogeneity can be realized.

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. The operation spring 1 is equipped with an auto key, and a thawing/cooking key 4 according to the present invention is provided in the auto key.

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 high frequency generating means 9, ie, a Macnetron.

As for heating, thawing is first performed using low power, and then cooking is performed using high power. 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 was improved through weight gain.

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 varies 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 can employ a capacitance method or a strain gauge method to detect the displacement amount of the mounting plate 11, or a vibration method to measure the natural frequency. Further, as the non-contact temperature sensor 12, a pyroelectric infrared sensor or a SAW sensor using surface acoustic waves can be used. 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 in thawing mode 'DEF'
and cooking mode ゜C○○ ni', and thawing mode is further divided into three small modes. First, T1 ends when the microwave is heated at full power and the surface temperature (I) reaches a predetermined value A. In this mode, the temperature of the frozen food is raised all at once, and the food shifts to the next T2 mode, that is, rest mode, before the surface of the food is boiled. The T2 time is calculated by T2=2T1 (K2: constant) based on the T1 time, and during this time carryover heating is performed to eliminate temperature unevenness. (B) in Figure b is the temperature at the center of the food, but the center is difficult to thaw, and even if the surface CI+ rises to A'C in T1 mode, the center still remains ice. Therefore, in T2 mode, the surface temperature drops again and begins to freeze. This is the role of T2 mode. In addition to this, the T2 time may be determined by detecting the point at which the surface temperature returns to a certain temperature, for example 0°C, using a non-contact temperature sensor, or by determining 2W (K2 constant number) to T2 based on the weight of the food. good.

Continued (T3 mode is a mode in which the power is reduced to prevent the surface from boiling while thawing the center of the food; T3 =
Calculate the time using 3W (K3: constant). In other words, the time is controlled based on the weight detected by the weight sensor.

Once thawing is completed through these steps, the next step is to move to the cooking mode "C00K". Here, the time t4 until the surface temperature of the food reaches a predetermined temperature B is counted, and based on this, T4 = t4 + Kt4 (K: constant).

K may be zero.

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

1' Effects of the Invention 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 center.

(2) At the end of the thawing mode, there is little difference in the degree of melting of each part, and it is possible to thaw and cook with a finish that does not become mushy without compromising homogeneity in subsequent cooking.

(3) Automatic thawing and cooking can be performed using a weight sensor and a non-contact temperature sensor.

(4) At the beginning of the thawing mode, a non-contact temperature sensor is used to raise the surface temperature of the food to a certain value, so even if the frozen temperature is different or it has been a long time since it was taken out of the freezer, it will be corrected during the T1 mode. There is little variation in the degree of defrosting.

[Brief explanation of the drawing]

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, Fig. 3a,
b is a diagram showing the same heating pattern. 4... Thawing cooking key, 5... Control unit, 6
... Heating chamber, 7 ... Heated object, 9 ...
... High frequency generation means, 10 ... Weight sensor,
12...Non-contact temperature sensor. Name of agent: Patent attorney Toshi Nakao, Idiot 1
Figure/Figure 2 Part b 4 System S; 3S8 Eny○ Part 03. 3,5;1 Enemy Reitobaba〆29 ・)15 6 Do, Ji1 Stick\i , JP-A-Sho GO-258894 (4) Figure 3 ((1) 1″□

Claims (1)

[Claims] A heating chamber in which the object to be heated is placed, a high frequency generating means coupled to this heating chamber, a control section for controlling power supply to the high frequency generating means, and a weight for inputting the weight of the object to be heated to this control section. It consists of a sensor, a non-contact temperature sensor that detects the surface temperature of the object to be heated, and a key that commands thawing cooking,
The control unit detects the weight of the object to be heated using the weight sensor based on the input of the key, calculates at least a part of the thawing time based on the weight, and then switches the high frequency output to start cooking. A high-frequency heating device configured to perform the following steps and to control the end of cooking using the non-contact temperature sensor.