JPH0821685A - Electromagnetic wave heater - Google Patents

Abstract

PURPOSE:To realize efficient heating while agitating and uniformly heating an object to be heated by rotating a polygonal heating vessel at each predetermined time, and always opposing its one corner toward a microwave radiating direction. CONSTITUTION:A microwave is guided from the magnetron of a microwave generator to a waveguide 2. The waveguide 2 is longitudinally disposed, and its microwave output is guided from below to above. A heating vessel 3 of a network structure having low dielectric loss and square side faces is so disposed on the way of the waveguide 2 that one of the corners is directed downward, and an object 4 to be heated is disposed therein. The vessel 3 has a structure which can be rotated at the center of the side face as a center, and is so rotated that the adjacent corner is opposed to the electromagnetic wave direction each time of radiating the wave for a predetermined time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating device for heating an object using electromagnetic waves including microwaves. Particularly suitable for drying raw foods.

[0002]

2. Description of the Related Art Heating devices using microwaves are already widely used in microwave ovens for home use, including industrial use. Heating a substance having a large dielectric loss, such as water, by utilizing heat generated in proportion to the magnitude of the dielectric loss when exposed to microwaves. Many heating devices (for example, reference: “Nikkei New Material March 30, 1992)
As shown in FIG. 5, a turntable 7 is placed in an applicator 8 and an object to be heated is placed on the turntable 7 and rotated. Since the microwaves are irregularly reflected on the metal wall surface in the applicator 8 to irradiate the object, the microwaves are not sufficiently absorbed by the object and are largely reflected.

Therefore, in order to perform efficient heating, an applicator as shown in FIG. 4 (comparative example) is filed by the applicant of the present application in Japanese Patent Application No. 6-9029. In this case, the object to be heated is placed in a wedge-shaped or pyramid-shaped container with a low dielectric loss having a downwardly convex shape, and the microwave is irradiated from below, so that the reflection can be reduced and the efficiency is extremely high. It can be heated well.

[0004]

However, in a downwardly convex container as shown in FIG. 4, only the tip of the container is heated intensively, and as a result, only the tip is charred.

An object of the present invention is to provide an electromagnetic wave heating device which can realize uniform heating without the above drawbacks.

[0006]

An electromagnetic wave heating apparatus of the present invention has an electromagnetic wave generating apparatus, a waveguide for guiding electromagnetic waves, and a container for containing an object to be heated, said container being non-magnetic and having a low inductive loss. A rectangular shape, located in the waveguide, one convex direction of the container is arranged to face the direction of the electromagnetic wave, and the lateral shape of the container is triangular or square, or It is a rhombus and is characterized by a structure that can rotate around the center of the side surface.

Further, each time the heating vessel is irradiated with an electromagnetic wave for a predetermined time, the heating vessel is rotated such that the adjacent convex angle is opposed to the direction of the electromagnetic wave.

Furthermore, the heating container has a mesh structure.

[0009]

Next, the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram of an electromagnetic wave heating device showing one embodiment of the present invention. Microwaves are guided from the magnetron of the microwave generator 1 to the waveguide 2. The waveguide 2 is arranged vertically, and the microwave output is guided from the bottom to the top. Waveguide 2
A heating container 3 made of a resin having a low dielectric loss is placed in the middle of, and an object 4 to be heated is placed therein. The end of the waveguide has a cover of a punching metal 5 that allows gas to pass through but shields electromagnetic waves. The shape of the side surface of the heating container 3 is a quadrangle, and one corner is located directly below. By operating the microwave generator in such a state and irradiating the microwave from the lower side of the container, efficient heating with less reflection is performed. In this case, since the lower end of the container is intensively heated, the heating container 3 is rotated by 90 degrees about the center of the container at regular intervals without irradiation for a long period of time. Then, the corner next to it faces directly below. At the same time, the object to be heated also rotates, and a portion of the object to be heated 4, which has not been heated so much, is newly dropped to the corner facing downward, and heating is started. By repeating such an operation, the entire object to be heated can be uniformly heated.

The shape of the heating container 3 is shown here as a quadrangular shape, but as shown in FIG. 2, it may be a trigonal or pentagonal shape. All you have to do is face it. However, if the number of corners is too large, the sharpness of the corners may deteriorate, and the heating efficiency may decrease.

Further, as shown in FIG. 3, by forming the heating container into a mesh-shaped container 6, the exuded water is not accumulated, and the steam generated by heating can be efficiently extracted out of the heating container. .

[0012]

EFFECTS OF THE INVENTION By using the electromagnetic wave heating device of the present invention, it is possible to reduce partial burning due to the concentrated heating of the object to be heated, and to uniformly heat the whole. As a result, wasteful heating is reduced and power consumption is reduced.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an electromagnetic wave heating apparatus showing an embodiment of the present invention.

FIG. 2 is a view showing another embodiment of the present invention in which the shape of the heating container is changed.

FIG. 3 is a view showing a case where the heating container is in a mesh shape as another embodiment of the present invention.

FIG. 4 is a diagram showing a structure of an electromagnetic wave heating device having a wedge-shaped container of a comparative example.

FIG. 5 is a diagram showing a structure of a conventional microwave oven.

[Explanation of symbols] 1 electromagnetic wave generator 2 waveguide 3 heating container 4 object to be heated 5 punching metal 6 mesh container 7 turntable 8 applicator

Claims (3)

[Claims] 1. An electromagnetic wave generator, a waveguide for guiding electromagnetic waves, and a container for containing an object to be heated, the container having a non-magnetic, low inductive loss, and rectangular shape. And one side of the container is disposed so as to face the direction of the electromagnetic wave, and the side shape of the container is triangular, square, or rhombic, and can rotate around the center of the side. An electromagnetic wave heating device characterized in that: 2. The electromagnetic wave heating device according to claim 1, wherein each time the container is irradiated with an electromagnetic wave for a certain period of time, the adjacent convex corners face each other in the direction of the electromagnetic wave. 3. The electromagnetic wave heating device according to claim 1, wherein the container has a mesh structure.