JPS5927133A - High-frequency heater - Google Patents

Abstract

PURPOSE:To thaw frozen foods more ideally without failure by a method wherein an indicating unit for providing an user with an information obtained by a temperature sensor through a control unit including micro-computers. CONSTITUTION:An input unit 1 is provided with a defrost key 2 capable of selecting the defrosting while it is also capable of setting the weight of the frozen food simultaneously by the operation of a tap. The temperature sensor 6 is provided in a heating chamber 7 at a position capable of detecting the atmosphere of the interior of the heating chamber 7 while the approximate value of a temperature is indicated in the indicating tube 5 of the central control unit 4 by the temperature information of the temperature sensor 6. The user coincides the indication of a temperature correcting lamp 9, provided below said temperature indicating value, with said indication in accordance with the indicated temperature by the tap control of a temperature key 8, provided in the input unit 1. Next, when a start signal is inputted into the input unit 1 and first relay 11 is put ON, the high-frequency wave is oscillated by a high-frequency oscillating circuit consisting of a high-voltage transformer 12, a magnetron 15 and the like. Said relay 11 is put ON or OFF in accordance with a pattern memorized in the micro- computer of the central control unit 4 previously based on the kind of the food to be heated, which has been inputted selectivey into the input unit 1.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to the thawing of frozen foods by high frequency heating.

Conventional structure and problems In general, there are two types of thawing: external heating thawing using heat conduction and internal heating thawing using high frequency heating.External heating thawing involves placing the area around the food at a higher temperature than the temperature of the food, and the heat is transferred to the frozen food. Thawing is caused by heat sensitivity, which increases the enthalpy of the food.

In this method, the frozen food thaws from the periphery to the center. External heating thawing involves thawing using an electric heater, hot water, infrared light bulb, etc. External heating thawing takes a long time because food products generally have poor thermal conductivity. When the outer layer melts and becomes water, that part has a lower thermal conductivity than ice, so the conduction to the inside becomes poor. It takes almost twice as long as the time required for freezing. The fact that thawing takes a long time results in quality differences even in the solid state immediately after thawing.

In contrast, defrosting using high-frequency radio waves generates heat in the food itself to increase enthalpy and defrost the food. Thawing progresses very quickly as the frozen food itself is used as a heating element to thaw from the surface and from the inside using radio waves.
For this reason, the quality of the solid is generally uniform and stable.

Although internal heating thawing is superior to external heating thawing, conventional high-frequency heating equipment requires careful consideration of the ambient temperature, radio wave distribution, the size, shape, and weight of frozen foods, and the difference in dielectric constant between water and ice. Because this was not done, problems often occurred when thawing with a high-frequency heating device.

In order to eliminate the drawbacks of thawing using high-frequency heating, in recent years a cylindrical four-wave heating system has been developed that uses a microcomputer (hereinafter abbreviated as microcomputer) to control the heating pattern according to the weight of the frozen food. has been well received in the market.

That is, each stage has a plurality of execution stages consisting of a predetermined constant high frequency output, and the execution time of each stage is stored in advance in the microcomputer according to the weight of the food input from the weight input section. By calculating by a function and inputting a signal to start thawing cooking, the above-mentioned plurality of predetermined execution steps are executed, thereby achieving faster and better thawing of frozen foods. According to this method, above the external temperature of the food! 1, the internal temperature can be raised most ideally,
This was only possible when the outside temperature and the temperature inside the heating chamber were at a certain temperature. In other words, there can be a 40 degree difference in external temperature between summer and winter, and among high-frequency heating devices, the so-called microwave oven with a built-in electric heater, which is the most widely available on the market,
When the frozen food was thawed after heating, the temperature of the food was completely different. This has some disadvantages, such as the fact that unthawed food ends up being kneaded or heated due to the environment, or conversely, most of the food ends up being boiled.

OBJECTS OF THE INVENTION The present invention solves the above-mentioned conventional drawbacks, and aims to thaw frozen foods more efficiently and with fewer failures under any conditions.

In order to achieve the second object of ``Structure of the Invention'', the high-frequency heating device of the present invention is provided with a temperature sensor that detects the internal temperature of the heating chamber, and the information obtained by the temperature sensor is transmitted via a control unit including a microcomputer. In addition to displaying information on the display section for providing information to the user, it also has an input section for adjusting the finished product that allows the user to select a heating pattern based on the temperature information. If the temperature is so high that heating cannot be performed, the control configuration is such that heating is not performed even if a start signal is input.
It has the effect of being able to defrost frozen foods quickly and with almost no failures even under any environment.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

1 to 3, the input unit 1 has a thawing key 2 for selecting thawing, and the thawing key 2 can also set the weight of the frozen food by tapping at the same time. When an input signal is input to this decompression key 2, the signal is sent via an input control section 3 to a central control section 4 including a microcomputer. The central control unit 4 displays the set weight on the display tube 5 based on the input signal. Further, the temperature sensor 6 is provided at a position where it can detect the atmosphere inside the heating chamber 7, and based on the temperature information from the temperature sensor 6, the central control section 4 displays an approximate temperature value on the display tube 5. The user selects the input section 1 according to the displayed temperature.
By tapping the temperature key 8 provided in the
Match the temperature correction lamp 9 below the displayed temperature value.

Next, when a start signal is input to the input section 1, the relay drive control section 10 turns on the first relay 11 via the input control section 3 and the central control section 4. When the first relay 11 is turned on, a high frequency oscillation circuit including a high voltage transformer 12, a high voltage capacitor 13, a diode 14, and a magnetron 16 oscillates a high frequency. Moreover, the first relay 11 is
Depending on the type of the object to be heated that is selectively inputted into the input section 1, it is turned on and off according to a pattern stored in advance in the microcomputer of the medium heat control section 4. 1
9 is a low voltage transformer that supplies power to each control section. Reference numeral 17 denotes a heater for electrically heating the object to be heated, and is turned on and off by the second relay 16.

The operation of the above-mentioned configuration Kjb will be explained below based on FIGS. 4 to 6.

1. The high-frequency cutting operation pattern and the temperature of the frozen food 18 when the internal temperature of the heat chamber 7 of the force 11 is in a normal state, that is, around 10"C to 20°C, and the frozen food 18 is thawed. The relationship of increase is shown in Figure 5 a and b. In the same figure, first, continuous high output takes a certain period of time T1, and then changes to intermittent output after a pause time T2. After this time T3, further After a pause time T4, the operation ends with the final intermittent small output operation.This intermittent small output time is defined as T5.The output level and time of each of these are as follows.
This pattern is determined by multiplying the input weight of the frozen food by a pre-stored function, and the temperature rise in the center part B and surface part A of the frozen food 18 in the figure always remains below 5°C. , ideal thawing can be performed.

Next, a description will be given of defrosting when the temperature inside the heating chamber 7 is relatively high, that is, after continuous operation or in midsummer. FIG. 6C shows the frozen food 18 when the heating operation is performed in the same manner as the heating pattern described above even though the temperature inside the heating chamber 7 is high.
As is clear from the figure, the temperature of the surface area A is due to both the high frequency and the external atmosphere heating, and the rising force 1-p is steep, and the temperature rises to 0°C, where ice becomes water. From the vicinity, the dielectric constant suddenly becomes a dog, resulting in an even more rapid increase and VC boiling down for a short time. Figure 6 a, b
As mentioned above, when the internal temperature of the heating chamber 7 is high, the heating pattern is the one in which the temperature is corrected by the temperature ghee 8,
This is a diagram showing the relationship between the temperature rise of frozen foods.As is clear from the diagram, the continuous high output operation time T1 is shortened, and the rest time T1 is shortened.
By lengthening the temperature of the frozen food 18, the temperature of the frozen food 18 can be thawed in an ideal manner without any sudden rise in temperature.

Next, when thawing food at an extremely high temperature after heating with the electric heater 17 for open cooking, etc., the surface area A can be boiled in a short time even with a small amount of high-frequency output irradiation. By displaying the temperature, the user can use it as a guide for the cooling waiting time. Also, if
Even if the user gets sick and sends a start signal, the microcomputer is programmed so that high-frequency oscillation does not occur above a certain temperature (approximately 100"C).

In this way, according to this embodiment, a heating pattern is selected according to each environment, and a speedy and precisely thawed state can be obtained. In addition, when the temperature is high, the user can know the approximate waiting time,
Even if you accidentally start the food, you won't have to waste food and have many other benefits. It should be noted that when heating with an electric heater, the temperature is generally controlled using a temperature sensor, and this is not a cost amplifier at all in the case of an electric heating device or a high frequency heating device.

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

(1) Frozen foods can be thawed quickly and in the best condition according to their weight, and when the temperature is extremely high, the user can receive information such as estimated waiting time and danger signals, etc., and improve performance. It is possible to provide a high-frequency heating device that is extremely easy to use.

+2) There will be no thawing failures when the temperature inside the heating chamber is extremely high, and there will be no wastage of frozen foods.

(3) Even under any demand environment, the shortest heating operation time and the best thawing condition can be obtained depending on the temperature condition.

[Brief explanation of the drawing]

Fig. 1 is an external perspective view of a high-frequency heating device that is an embodiment of the present invention, Fig. 2 is a control circuit diagram of the device, Fig. 3 is an external perspective view of the main parts of the device, and Fig. 4 is a frozen food product. 5a, b, c and 6a. b is a diagram showing the operating characteristics of the device during thawing and heating. 0 1... Input section, 2... Thawing key, 3.
... Input control section, 4 ... Central control section, 5
...Display tube (display section), 6...Temperature sensor, 7...Heating chamber, 9...Temperature correction lamp, 15...・Magnetron (high frequency generation means), 17... Electric heater, 18...
Frozen food (items to be heated). Name of agent: Patent attorney Toshio Nakao and 1 other person No. 3
Figure 5 Figure 4 Figure 5 Shoulder T (crying)

Claims (3)

[Claims] (1) A heating chamber for storing and heating an object to be heated, a high-frequency generating means for high-frequency heating the object to be heated, an input section for selectively inputting the type and weight of the object to be heated, and the input section a control unit for controlling the high-frequency heating according to a predetermined heating pattern according to the type and weight of the object to be heated inputted to the heating chamber; a temperature sensor for detecting the temperature in the heating chamber; a heating time, etc. and a display section that displays , and when thawing heating is input to the input section and the temperature inside the heating chamber is higher or lower than normal temperature, the high frequency heating is configured to display the temperature status on the display section. Device. (2) Control programmed to not perform heating operation even if heating start signal is input when thawing and heating of frozen food is input to the input unit and the temperature inside the heating chamber is extremely high or low. A high-frequency heating device according to claim 1. (3) The high-frequency heating device according to claim 1, wherein the input section has a temperature key for changing the heating pattern.