Patent ID: 9648670
Date: 2017-05-09
CPC Classifications: H05B

Claim:
1. A microwave heating device comprising: a microwave oscillation portion including plural phase-locked loops connected to a single reference-signal oscillator and having plural outputs; plural amplification portions for amplifying the respective outputs from the microwave oscillation portion; plural radiation portions which are adapted to be supplied with outputs from the amplification portions and to radiate microwaves to a heating chamber; and a control portion for controlling the microwave oscillation portion, wherein each of the radiation portions has plural microwave feeding points, the respective outputs from the amplification portions are supplied to the respective microwave feeding points, the radiation portions are antennas having a substantially-disc shape, the radiation portions are placed on the same wall surface of the heating chamber, wherein the radiation portions are not placed on the rest of wall surfaces of the heating chamber, the radiation portions and the microwave feeding points in the radiation portions placed on the same wall surface of the heating chamber are placed symmetrically with respect to a line passing through an approximate center of the wall surface; one microwave feeding point in the respective radiation portions is placed on a line connecting a respective center points of the respective radiation portions to each other, and another microwave feeding point of the respective radiation portions is placed on a respective lines which pass through the center points and are orthogonal to the line connecting the respective center points to each other.