Sanyo Electric Co., Ltd.

Katsuaki Hayami

Yoshiharu Omori

Masaru Noda

Eiji Fukunaga

Kuniyasu Kubo

Hiroyuki Uehashi

Takashi Fukuda

Yuichi Otsuki

Masaharu Katayama

Haruo Sakai

Yoshihito Fukuda

Katsunao Takahashi

Yoshitsugu Kawamura

Chizuko Konishi

Yoshihiro Wada

Yukihiro Kitada

Yoshitsugu Takada

Kayo Sakata

Hideo Fujii

Microwave heating device

A microwave oven has a heating chamber formed inside a body frame. A radiation antenna is provided below the heating chamber. The radiation antenna is structured in such a way that a member housed in an antenna drive box appropriately operates to change the distance between a bottom surface of the body frame and the radiation antenna. Microwaves generated by a magnetron are supplied through a waveguide and the radiation antenna into the heating chamber. When the level at which the radiation antenna is positioned is changed, the way to supply microwaves from the radiation antenna into the heating chamber is accordingly changed. Specifically, microwaves are locally supplied into the heating chamber or supplied uniformly into the whole of the heating chamber.

Microwave oven capable of changing the way to supply microwaves into heating chambers

The microwave oven is provided with a magnetron and a wave guide. The wave guide is formed by a combining portion and a matching portion. The magnetron is provided with a magnetron antenna, and the magnetron antenna projects into the combining portion. The combining portion has one end connected to the matching portion, and has a structure in which the cross-sectional area does not change in the horizontal direction. The matching portion has a structure in which its cross-sectional area increases toward the side surface of a heating chamber. An antenna is provided on a mica board in the portion connecting a matching portion with another matching portion.

High frequency heating apparatus having a wave guide introducing microwaves into heating chamber

A microwave oven in which a plurality of projections are formed on an interior surface of a cavity for reflection and distribution of microwaves. The plurality of projections are dispersedly arranged so that neighboring projections do not contact each other. With this arrangement, microwaves can be efficiently distributed within the cavity, since the interior surface of the cavity does not have any depressions which would converge microwaves.

Microwave oven with a projection for uniform heating within the cavity

A microwave oven includes a cavity in which food is accommodated, a magnetron for generating microwaves, and a waveguide to supply microwaves generated from the magnetron into the cavity. The waveguide has substantially a truncated cone configuration in which the cross sectional area at the cavity side is greater than the cross sectional area at the magnetron side, and an output antenna of the magnetron is disposed to project from the bottom of the waveguide at the magnetron side into the inner space of the waveguide. The microwave oven further includes a flat radiation antenna fixed in the inner space of the waveguide around the output antenna of the magnetron while maintaining distances from the waveguide and the output antenna of the magnetron in which no spark is generated. Therefore, the radiation area for emitting the microwaves is increased significantly to improve heating nonuniformity within the cavity.

Microwave oven including antenna for radiating microwave

Growing community of inventors

Otsu, Japan

Katsuaki Hayami