JPS583172B2 - High frequency heating device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a high-frequency heating device for heating an object using radio wave energy, and more particularly to a means for controlling the heating of an object to be heated by the device.

It is well known that radio wave energy in the microwave band is used to heat objects.The conventional configuration of such high-frequency heating devices is to directly or guidedly emit radio waves from a radio wave source such as a magnetron. It has a structure in which it is supplied through a wave tube to the inside of a cavity called an oven, where the object to be heated is housed.

In the apparatus having such a configuration, the heating time of the object to be heated is usually controlled by a timer such as a timer.

In this case, it is necessary to adjust the heating time appropriately depending on the type of the object to be heated, that is, the difference in dielectric loss coefficient, the weight, and the initial temperature, that is, the temperature of the object before heating.

If the time adjustment is inappropriate, the object to be heated may be undercooked or overcooked.

The conventional method to solve this problem is to insert a temperature detection element into the object to be heated, directly detect the temperature of the object, and control the oscillation of the magnetron to control the heating of the object. has been carried out.

In the device having such a means, the object to be heated loses its shape,
This may cause damage by interfering with cooking.

SUMMARY OF THE INVENTION Therefore, it is an object of the present invention to provide a means for controlling the heating of an object to be heated, which does not depend on the type, weight, or initial temperature of the object and does not cause the object to lose its shape.

More specifically, it is desired to detect a physical change in the air flow passing through the cavity and control a radio wave generation source using the signal to control the heating of the object to be heated, and to reliably configure such a means. There is an aim of the present invention.

Examples will be described below with reference to the accompanying drawings.

In FIG. 1, 1 is the main body of the device, and 2 is a door attached to the main body 1 so as to be openable and closable.

The main body 1 has a cavity 3 as shown in FIG. 2, and a door 2 is disposed to close an entrance/exit (not shown) of the cavity 3 for the object to be heated.

In FIGS. 2 and 3, 4 is a magnetron that is a radio wave generation source.

Reference numeral 5 denotes a blower for cooling the magnetron 4. The blower 5 is surrounded by an air guide 7, and the air guide 7 is provided with a blower intake port 6.

8 is an exhaust air guide for cooling the magnetron 4, and 9 is an antenna cover that surrounds the antenna section of the magnetron 4.

The antenna cover 9 is made of a dielectric material with low loss at high frequencies.

10 is a rotating saucer, and the heated object 1 is placed in the rotating saucer 10.
3 is placed, and the rotating saucer drive motor 11 is used as a drive source,
The coupling piece 12 connects the rotary saucer drive motor 11
A driving force of
It is configured to perform rotational movement using the center of rotation as the center of rotation.

14 is an intake duct, and 15 is an intake opening formed in the cavity 3.

The wind entering the cavity 3 is introduced into the cavity 3 via the intake duct 14 and through the intake opening 15 .

Reference numeral 16 denotes an exhaust opening disposed in the cavity 3, and the exhaust opening is constituted by a metal pipe 21 in order to prevent interference radio waves.

17 is an exhaust duct.

The air leaving the cavity 3 is exhausted through the exhaust opening 16 and through the exhaust duct 17 .

One end of the exhaust duct 17 is disposed near the blower intake port 6 and configured so that the intake force of the blower 5 acts on the exhaust duct 17.

Reference numeral 18 denotes a detection element for detecting physical changes in the wind, that is, airflow, and in this embodiment, an element such as a thermistor that is sensitive to temperature changes in the airflow is used.

19 is an amplification means for amplifying the signal of the detection element 18;
20 is operated by the output generated from the amplification means 19;
This is a control means for controlling the oscillation of the magnetron 4.

Reference numeral 22 denotes a control valve that is a means for adjusting the flow rate of outside air introduced into the sensing element 18 section, and the control valve 22 is operated by a valve drive section 23 to adjust the flow rate of the airflow according to the setting conditions of the operation section 24. .

The operating section 24 has a movable knob 25 on the control panel of the main body 1, as shown in FIG.

Furthermore, it has a pointer 26 linked to the movable knob 25, and a display plate 27 facing the pointer 26 and showing operating conditions.
is installed.

The setting conditions of the movable knob 25 are displayed on the display board 27.

For example, the following information may be displayed.

(1) Conditions for the finishing temperature of the heated item, such as hot or lukewarm.

(2) Temperature conditions before heating the object to be heated, such as frozen, refrigerated, room temperature, etc.

(3) Conditions for the amount of food to be heated such as one serving, two servings, three servings, etc.

(4) Conditions regarding the type of food to be heated, such as alcohol, milk, and rice.

(5) Conditions for high frequency output such as high heat and low heat.

(6) Wrap. Conditions under which the object to be heated is heated, such as the presence or absence of a container and the height of the shelf board.

(7) Conditions of other heat sources, such as with or without heater heating.

28 is a hot air introduction port provided in the exhaust duct 17 to introduce hot air.

The flow rate of the hot air is adjusted by the regulating valve 22 through the hot air inlet 28, and the hot air is conducted to the sensing element 18 portion in a mixed flow with the air flow passing through the cavity 3.

29 is a heat source of hot air, and a heating element such as a lamp or a heater is used.

Next, the operation of the above embodiment and the effects of each part will be explained.

Radio waves generated by the magnetron 4 are radiated into the cavity 3 and heat the object 13 to be heated.

The object to be heated 13 rotates together with the rotating saucer 10 and is uniformly heated.

As the heating of the object to be heated 13 progresses, the object to be heated 13
The radiant heat radiated from increases.

This heat is transferred to the sensing element 18 by the wind passing through the cavity 3.

The detection element 18 generates a signal in response to a change in the radiant heat of the object 13 to be heated.

The signal generated from the sensing element 18 is amplified by the amplification means 19 and transmitted to the control means 20.

Therefore, when the object to be heated reaches a desired temperature, the control means 20 is activated, the oscillation of the magnetron 4 is controlled, and the heating of the object to be heated is controlled.

The present embodiment operates as described above.

Incidentally, the first feature of this embodiment is that the heating of the object to be heated is not controlled by a timer.

Therefore, since it is not necessary to adjust the heating time, the heating of the object to be heated can be controlled to a desired temperature regardless of the type, weight, or initial temperature of the object to be heated.

The second feature is that it is a so-called indirect detection method that detects temperature changes of the heated object without directly inserting the sensing element 18 into the heated object, so the heated object does not lose its shape. .

The third characteristic is the uniqueness of the wind path.

That is, as described above, the airflow passing through the sensing element 18 is a mixture of the airflow passing through the cavity and the outside air, and the flow rate of the outside air can be controlled from the outside.

The effect of adjusting the flow rate of outside air is that the response of the sensing element 18 to the progress of heating the object to be heated can be changed.

In other words, when the flow rate is increased, the response tends to be delayed, and when the flow rate is decreased, the response tends to be faster.

Therefore, the following adjustment enables more accurate heating control of the object to be heated.

(1) Increase the flow rate when concentrating the finishing temperature.

(2) Increase the flow rate for foods that have a low temperature before heating, such as frozen foods.

(3) If the amount is large, such as three or four servings, increase the flow rate.

(4) Reduce the flow rate when heating foods that are finished at low temperatures, such as in sake pots.

(5) In the case of "low heat" where the high frequency output is low, reduce the flow rate.

(6) When heating in a container with a lid, the flow rate should be reduced if the height of the shelf board is lowered and heated away from the detection element.

(7) When using other heat sources such as a heater, increase the flow rate.

Here, when the conditions of the cases shown in (1) to (7) are reversed, the flow rate adjustment is also reversed.

In order to easily perform the above adjustments from the outside, a movable knob 25 is provided as an operating means, and a pointer and a display board 27 are provided as display means on the control panel section of the main body 1. (1) to (7)
By specifying the conditions shown in the example above, adjustments can be made easily and clearly.

As described above, according to the present invention, the heating of the object to be heated can be controlled without deforming the object regardless of the type, weight, or initial temperature of the object to be heated, and the means for doing so can be reliably configured. It is possible to provide a high-frequency heating device that can.

In addition, in the embodiment, a configuration was presented in which the oscillation of the magnetron is controlled by capturing the temperature change of the airflow passing through the cavity, but the configuration is not necessarily limited to such a configuration.
For example, the idea of the present invention can also be applied to a structure in which the heating of the object to be heated is controlled by controlling the oscillation of a magnetron using other physical changes such as changes in the humidity of airflow due to water vapor generated from the object to be heated. Needless to say, it can be done.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a high-frequency heating device according to the present invention;
FIG. 2 is a schematic vertical cross-sectional view of the main part, and FIG. 3 is a schematic cross-sectional view of the main part. 1...Main body, 3...Cavity, 4...
...Magnetron, 5... Prowa, 18...
...Detection element, 25...Movable knob, 26.
...Guidelines, 27...Display board.

Claims (1)

[Claims] 1. A cavity 3 for storing an object to be heated, an opening through which air flows, and a physical change in the air flow near the outlet of the opening. A high-frequency heating device characterized by comprising a detection element 18 for detecting the detection element 18, a means for introducing outside air into the detection element 18, a means for adjusting the flow rate of the outside air, and a means for operating the same from the outside. 2. The high-frequency heating device according to claim 1, characterized in that means for operating the device from the outside is provided in the control panel section of the main body 1.