JPS5926210B2 - 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 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 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.

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, the present invention aims to provide a means for controlling the heating of an object to be heated, regardless of the type, weight, or rice temperature of the object to be heated, and which does not cause deformation of the object.

More specifically, the method detects the physical change in the airflow passing through the cavity, controls the radio wave generation source using the signal, and controls the heating of the object to be heated. The aim of the present invention is to reliably configure the following.

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 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 9 surrounding 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 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 .

16 is an exhaust opening formed in the cavity 3, and 17 is an exhaust duct.

The intake opening 15 has a larger ventilation area than the exhaust opening 16.

The intake port is composed of a group of small holes in order to prevent the generation of loud radio waves due to the large area.

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

That is, in FIG. 3, the L key ψ is configured.

Further, the intake opening 16 is connected to the rotation axis 0-0' of the rotating tray 10.
The basic axis x-x in the width or depth direction of the cavity 3 perpendicular to
They are arranged approximately symmetrically with respect to '.

The wind leaving the cavity 3 passes through the exhaust opening 16 and enters the exhaust duct 1
It is exhausted through 7.

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 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;
0 is a control means that is operated by the output generated from the amplification means 19 and controls the oscillation of the magnetron 4.

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 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.

By the way, the first feature of this embodiment is that the heating of the object to be heated is not controlled by a time limiter.Therefore, since it is not necessary to adjust the heating time, the type of object to be heated,
It becomes possible to heat and sterilize the object to be heated to a desired temperature, regardless of the weight or the temperature of the rice.

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 air intake opening 15 has a larger ventilation area than the exhaust opening 16.

As a result, even when the rotating saucer is rotating to monitor the progress of heating the object, the airflow is responsive to the progress of heating the object, and the heating of the object can be reliably controlled.

It is preferable to appropriately select the degree of enlargement depending on the structure of the cavity 3, but as a guide, it is good to make the long side 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 10.
No matter where the device is placed, the airflow can reliably capture the heating progress.

In addition, the arrangement of the intake opening 15 in the cavity 3 is preferably arranged in a manner that is distributed across the above-mentioned basic axis x-x'c.
If possible, it is desirable to make it approximately symmetrical with respect to the base axis xx' (G).

As a result, even in the cavity 3 having the rotating saucer 10,
By capturing physical changes in airflow, it becomes possible to reliably control the heating of objects 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 side sectional view of the main part, and FIG. 3 is a schematic top view of the main part. 3...Cavity, 10...Rotating saucer, 15
...Intake opening, 16...Exhaust opening, 18...Detection element.

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 high-frequency heating device characterized in that it is equipped with a detection element 18 that detects physical changes in the air, and that an exhaust opening 16 is larger than an intake opening 15. 2. The high-frequency heating device according to claim 1, wherein the intake opening 15 has one side substantially equal to the rotating saucer 10. 3. In claim 1, the intake openings 15 are arranged to be distributed with respect to the base axis x-x' in the width or depth direction of the cavity 3, which is orthogonal to the rotation axis of the rotating saucer 10. High frequency heating device. 4. The high-frequency heating device according to claim 3, characterized in that the intake openings 15 are distributed symmetrically with respect to the base axis xx' of the cavity 3.