JPS5920992A - High frequency heating device - 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 high-frequency heating device for dielectrically heating an object housed in a heating chamber using high-frequency waves.

Conventional configurations and their problems Conventional microwave ovens, which are high-frequency heating devices, for example, have a method of stirring the high-frequency waves supplied into the heating chamber with a stirring blade as a method of uniformly heating the object to be heated in the heating chamber. There is a method in which the object to be heated is placed on a rotating table provided in the heating chamber and rotated, or a method in which a high frequency radiator, that is, a rotating antenna is rotated in the heating chamber. Among these methods, the method in which the rotary antenna is rotated within the heating chamber occupies the smallest portion of the heating chamber, so that the effective volume of the heating chamber can be increased or the main body of the microwave oven can be made more compact. Compared to other methods, this method of rotating a rotating antenna within a heating chamber is very important in the dimensions and shape of the heating chamber, and if the dimensions of the heating chamber change or the position of the rotation axis of the rotating antenna changes.

The shape and dimensions of the rotating antenna also vary widely.

Another drawback is that even if the rotating antenna has the same shape, if one dimension changes depending on the layer of wavelength used, not only the high frequency distribution characteristics within the heating chamber but also the output characteristics of the high frequency oscillator will change completely.

Purpose of the Invention The present invention solves the above-mentioned conventional drawbacks, and aims to reduce the amount of high-frequency radiation radiated vertically from a rotating antenna and the amount of high-frequency radiation radiated horizontally from a horizontal antenna provided on a single-rotation antenna. The object of the present invention is to provide a high-frequency heating device that can uniformly heat an object by adjusting the distribution characteristics of high-frequency waves in a heating chamber and the radiation direction.

Structure of the Invention In order to achieve the above object, the high frequency heating device of the present invention has the following features:
a heating chamber for accommodating an object to be heated; a high-frequency oscillator that supplies high-frequency waves into the heating chamber via a waveguide; a rotating antenna provided facing approximately perpendicularly into the heating chamber from the waveguide; It consists of a plurality of horizontal antennas provided on a rotating antenna, and the horizontal antenna is arranged asymmetrically with respect to the rotating antenna, and the amount of high frequency radiation radiated in the vertical direction from the rotating antenna and the rotating antenna together with the horizontal antenna are arranged asymmetrically. The radiation amount and radiation direction of high frequency waves radiated horizontally from the rotating horizontal antenna can be adjusted by changing the dimensions and shape of the horizontal antenna, thereby improving the distribution characteristics of high frequency waves in the heating chamber and making the object to be heated more uneven. Can be heated without dielectric heating.

Furthermore, since the proportion of the rotating antenna in the heating chamber is small, the effective volume can be increased.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 to 7.

In Fig. 1, 1 is the main body of the high frequency heating device.

A door 3 is provided at the opening of a heating chamber 2 provided within the main body 1 so as to be openable and closable. 4 is a heater plate provided on the top of the main body 1, and when boiling food etc. with this heater plate 4, the operation knob A provided on the front of the main body 1 is used.
6 is configured to be able to control the electric power of each of the plate heaters 6 shown in FIG. Reference numeral 7 denotes an operation knob B for controlling the output of a magnetron 8 used as an example of a heater and a high frequency generator provided in the heating chamber 2.

In FIG. 2, 9 is a plate made of a heat-resistant dielectric material provided on the top of the plate heater 6, 010 is a heater provided on the top inside the heating chamber 2, and 11 is the bottom of the heating chamber outside the heating chamber 2. This is a heater installed in the The heater IQ, 11 can efficiently heat the inside of the heating chamber 2. 12 is a heat insulating material provided around the outer periphery of the heating chamber wall 13; 014 is a tapered waveguide that transmits the high frequency waves generated by the magnetron 8 into the heating chamber 2;
Reference numeral 16 denotes a rotating antenna that is provided so as to pass through the waveguide 14 and the upper wall 16 of the heating chamber and face the inside of the heating chamber 2. The rotating antenna 16 includes a plurality of horizontal antennas 1 as shown in FIG.
71L, 17b are provided, and a rotating antenna 16 and a horizontal antenna 17 are connected by a motor 19 via a belt 1B.
a, 17b are rotated. This horizontal antenna 17a
, 17b are provided asymmetrically with respect to the rotating antenna 15, and the length is set to be an integer multiple of the row of oscillation wavelengths from the magnetron β. It is structured as follows.

Figures 4 to 6 show the amount and direction of radiation of high frequency waves radiated from the rotating antenna 16 and the horizontal antennas 17a and 17b by changing the lengths of the horizontal antennas 17& and 17b. Horizontal antenna 17&
, 17b is the oscillation wavelength A, FIG. 6 is the diameter of the oscillation wavelength, and FIG. 6 is the length of the bar of the oscillation wavelength.

FIG. 7 shows another embodiment, in which the horizontal antenna 17 is configured in a fan shape, and a large number of small holes 2o whose oscillation wavelength is less than Mo are provided in order to reduce the weight and rotational torque of the horizontal antenna 17. It is something that

The operation of the above configuration will be explained below.

First, when the object to be heated is housed in the heating chamber 2 and the magnetron 8 is operated by external operation, the high frequency wave from the magnetron 8 passes through the waveguide 14 and is driven to rotate by the motor 19, the rotary antenna 15 and the horizontal antenna 17. The rotating antenna 16 and horizontal antenna 171L are supplied from 17b into the heating chamber 2, and the object to be heated is dielectrically heated.
By adjusting the lengths of the horizontal antennas 17a and 17b as shown in FIGS. 4 to 6, the high frequency waves radiated from the rotary antenna 17b can be transmitted to
The large horizontal antenna 17a eliminates high frequency radiation from
, 17b, or because the dimensions of the heating chamber 2 cancel out the high frequency waves 21 radiated from the horizontal antennas 17 & , 17b as shown in FIG. However, in order to improve the distribution characteristics of high frequencies within the heating chamber 2, the lengths of the horizontal antennas 17a and 17b are adjusted as shown in FIG. By radiating the high frequency wave 21 in the horizontal direction and the high frequency wave 21 in the horizontal direction from the horizontal antennas 172L and 17b in a well-balanced manner and rotating the one-rotation antenna 16 and the horizontal antennas 17a and 17b, the distribution characteristics of the high frequency wave in the heating chamber 2 can be improved. .

According to the high frequency heating apparatus of this embodiment, the object to be heated can be dielectrically heated evenly.

A horizontal antenna 17a provided on the rotating antenna 16.

Mainly by adjusting the length of the heating chamber 17b to an optimal size depending on the shape and size of the heating chamber 2, a balanced amount of high frequency radiation can be delivered into the heating chamber 2 from the rotary antenna 16 and the horizontal antennas 17a and 17b. Since the horizontal antennas 172L and 17b rotate, it is possible to dielectrically heat the object evenly.

Furthermore, since the proportion of the rotating antenna 15 and the horizontal antennas 17a and 17b in the heating chamber 2 is small, the volume within the heating chamber 2 can be effectively utilized, or the main body 1 can be made smaller.

In addition, a large number of small holes 20 are provided in the fan-shaped horizontal antenna 17,
If the horizontal antenna 17 is made lightweight, in addition to the above-mentioned effect, the torque of the rotating antenna 16 can be reduced.

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

(1) By installing multiple horizontal antennas asymmetrically on the rotating antenna facing into the heating chamber from the waveguide, the antenna can be moved vertically from the single rotating antenna.

The amount of high frequency radiation radiated horizontally from the horizontal antenna can be adjusted using the horizontal antenna.

Moreover, in order to rotate multiple horizontal antennas.

The high frequency distribution characteristics within the heating chamber are improved and the object to be heated can be dielectrically heated evenly. 0 (2) Even if the shape and dimensions of the heating chamber change, by changing the length of the horizontal antenna, the heating chamber can be heated evenly. Almost uniform high frequency distribution can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a high-frequency heating device according to an embodiment of the present invention, FIG. 2 is a front sectional view of the high-frequency heating device shown in FIG. 1, and FIG. 3 is a view of the rotating antenna shown in FIG. 2. Perspective view, 4th
6 is a schematic diagram of high frequency waves radiated from the rotary antenna shown in FIG. 2, and FIG. 7 is a perspective view showing another embodiment of the rotary antenna shown in FIG. 2. 2... Heating chamber, 8... Magnetron (
high frequency oscillator), 14...i-wave tube, 16...
...Rotating antenna, 17&, 17b...□・
horizontal antenna. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7

Claims (4)

[Claims] (1) A heating chamber that accommodates an object to be heated, a high-frequency oscillator that supplies high-frequency waves into the heating chamber via a waveguide, and a rotating antenna provided facing approximately perpendicularly into the heating chamber from the waveguide. and a plurality of horizontal antennas provided on the rotating antenna, the high-frequency heating device 0 having a configuration in which the horizontal antenna is provided asymmetrically with respect to the rotating antenna. (2) High-frequency heating device 0 according to claim 1, in which the horizontal antenna is configured in a fan shape. (3) The high frequency heating device according to claim 1, wherein the length of the horizontal antenna is an odd number multiple of % of the wavelength used. (4) The high-frequency heating device 0 according to claim 2, wherein the fan-shaped horizontal antenna is appropriately provided with holes that correspond to the wavelength used.