JPS5841412B2 - 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 energy in the microwave band is used to heat objects.

A common configuration of such high-frequency heating devices is a configuration in which radio waves emitted from a radio wave generation source such as a magnetron are supplied directly or through a waveguide to the inside of a cavity called an oven in which the object to be heated is housed. belongs to.

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

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 rice temperature, that is, the temperature of the object to be heated before heating.

If the time adjustment is inappropriate, the result will be that the object to be heated is under-heated or over-heated.

Conventionally, as a solution to this problem, a temperature sensing element was inserted into the object to be heated, and the temperature of the object to be heated was directly detected, and the oscillation of the magnetron was suppressed to control the heating of the object. methods are being used.

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

Therefore, the present invention is designed to
And heating the object without causing the object to lose its shape?
! The aim is to provide a 1m means.

More specifically, it detects physical changes in the airflow passing through the cavity, uses the signals to suppress the radio wave generation source, and controls the heating of the object to be heated. The aim of the present invention is to construct the means reliably.

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 FIG. 2, 4 is a magnetron which is a radio wave generation source.

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

8 is an exhaust air guide for the wind that cools the magnetron 4; 9 surrounds the antenna section of the magnetron 4;
It is a ventilation guide that guides the wind introduced inside.

The ventilation guide 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 tray to the drive motor 1.
1 is transmitted, and the rotation receiving tray 10 is rotated along the rotation axis 0-
It is configured to rotate around 07.

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 .

The wind introduced into the cavity 3 is guided by the ventilation guide 9,
It goes from the air outlet 21 to the object to be heated 13 .

16 is an exhaust opening formed in the cavity 3, and 1T 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 so that the intake force of the blower 5 acts on the exhaust duct 17.

Reference numeral 18 denotes a sensing element that detects physical changes in the wind, that is, airflow, and in this embodiment, an element such as a thermistor that senses 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 along the Il axis.

Incidentally, in this embodiment, the ventilation opening 21 has a larger ventilation area than the exhaust opening 16.

Moreover, the negative side has one side that is approximately equal to the diameter of the rotary receiving tray 10.

That is, in FIG. 3, it is configured to have an L orientation.

Furthermore, the air outlet 21 is connected to the base axis x-x' in the width or depth direction of the cavity 30, which is perpendicular to the rotation axis 0-0' of the rotating saucer 10.
They are arranged approximately symmetrically with respect to each other.

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 tray 10 and is uniformly heated.

As the heating of the object to be heated 13 progresses, the object to be heated 13
The amount of radiant heat emitted 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, it becomes possible to control the heating of the object to be heated to a desired temperature regardless of the type, weight, and temperature of the rice 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, the ventilation opening 21 has a larger ventilation area than the exhaust opening 16.

This makes it possible to reliably control the heating of the object to be heated even when the rotary tray is rotating to monitor the progress of heating the object.

It is preferable to appropriately select the degree of enlargement depending on the structure of the cavity 3, but as a guide, it is preferable that the long side is approximately the same size as the diameter of the rotating saucer 10.

In this case, the object to be heated is moved into the cavity 3 due to the rotation of the rotating saucer 100.
The airflow can reliably capture the heating progress no matter where the device is placed.

Further, the arrangement of the air outlet 21 in the cavity 3 is based on the aforementioned basic axis X-
It is preferable to distribute them with respect to X', and if possible, it is preferable to arrange them approximately symmetrically with respect to the base axis x-x'.

As a result, even in the cavity 3 having the rotary saucer 10, physical changes in the airflow can be detected to reliably control the heating of the object to be heated.

As described above, according to the present invention, it is possible to control the heating of the object to be heated without deforming the object, regardless of the type of the object to be heated or the weight and rice temperature, and the means for doing so can be reliably configured. A high frequency heating device can be provided.

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 cross-sectional view of the main part. 3... Cavity, 9... Ventilation guide, 10... Rotating confinement, 15... Intake opening, 16... Exhaust opening, 1
8... Detection element, 21... Air outlet.

Claims (1)

[Claims] 1. It has a cavity 3 for storing an object to be heated, and the cavity 3 includes:
The cavity 3 has an intake opening 15 and an exhaust opening 16 through which air flows. A ventilation guide 9 is provided in the cavity 3 to guide the airflow introduced from the intake opening 15, and the ventilation guide 9 includes a detection element 18 that detects physical changes in the air.
A high-frequency heating device characterized in that the air outlet 21 is larger than the exhaust opening 16. 2. The high-frequency heating device according to claim 1, wherein the air outlet 21 has one side that is approximately the same as the rotating saucer 10. 3. The high-frequency heating device according to claim 1, characterized in that the air blowing ports 21 are arranged in a manner that is distributed with respect to the basic axis X-X in the width or depth direction of the cavity 30, which is orthogonal to the rotation axis of the rotating saucer. . 4. The high-frequency heating device according to claim 3, characterized in that the air blowing ports 21 are distributed approximately symmetrically with respect to the base axis xx' of the cavity 3.