Panasonic Intellectual Property Management Co., Ltd.

Panasonic Corporation

Toshiyuki Okajima

Keiji Onishi

Hiroshi Nakatsuka

Takehiko Yamakawa

Toshio Ishizaki

Koji Yoshino

Tomotaka Nobue

Yoshiharu Omori

Hiroyuki Uejima

Kazuhiro Yahata

Makoto Mihara

Takashi Uno

Yoshiharu Oomori

Takanori Hirobe

Hiroyuki Uno

High frequency heating device is provided with heater disposed adjacent to mount base on which object to be heated is mounted and having a plurality of surface wave transmission lines electrically isolated from each other, and first and second high frequency power generators, each of which generates high frequency power having different frequency. Surface wave transmission lines receive at least one of the high frequency power generated by first high frequency power generator and the high frequency power generated by second high frequency power generator. According to this aspect, interference between the high frequency powers is not occurred and electromagnetic field coupling is not occurred. As a result, in the high frequency heating device provided with the surface wave transmission line using a periodic structure, uneven baking caused by the electromagnetic field coupling can be suppressed, and a heating state of an object to be heated can be easily controlled.

High frequency heating device

A microwave heating device mountable to an electric device, includes: a commercial power supply; an AC/DC converter which outputs a plurality of DC voltages according to power supplied from the commercial power supply; a controller which receives power from the AC/DC converter and totally controls the electric device; a microwave processing device using a compound semiconductor which receives a plurality of outputs of the AC/DC converter and outputs a microwave; and a plurality of loads connected between, of the DC voltages output from the AC/DC converter, a predetermined Vd voltage and ground through a plurality of contacts. The loads form a group of electric components in the electric device. The controller controls power supply to the loads, and controls on/off of the contacts to drive the loads by the Vd voltage regardless of the voltage of the commercial power supply.

Microwave heating device

A high-frequency heating device of the present invention includes at least one high-frequency power generating part, at least one high-frequency power unit including a quadrature modulation part and a high-frequency power amplification part, a radiation part, a modulation signal generating part, and a control part, and the control part supplies the modulation signal generating part with a plurality of pieces of subcarrier information respectively including pieces of information of offset frequencies and phases, generates an in-phase modulation signal and a quadrature modulation signal, performs quadrature modulation in the quadrature modulation part, and outputs a plurality of subcarrier waves.

High-frequency heating device

A radio-frequency heating apparatus includes a phase varying unit to vary the phase of radio-frequency power; and a plurality of antennas which are placed on the same plane in a heating chamber and radiate a plurality of radio-frequency waves. The radio-frequency waves have a predetermined phase difference caused by phase variation in the phase varying unit. A geometry information acquisition unit acquires the geometry of an object; and a control unit controls the phase varying unit so that the radio-frequency waves are in phase in a first mode, and the radio-frequency waves are in opposite phase in a second mode. The control unit switches between the first mode and the second mode based on the acquired geometry information.

Radio-frequency heating apparatus and radio-frequency heating method

A high-output electric power amplifier using a depression-type FET includes a drain voltage supply portion adapted to create a positive voltage to be applied to a drain terminal in the depression-type FET, and a gate bias voltage supply portion adapted to create a negative voltage to be applied to a gate terminal in the depression-type FET, wherein the drain voltage supply portion uses an external commercial power supply as an electric power source, and the gate bias voltage supply portion uses a battery as an electric power source, in order to certainly prevent breakdowns of the FET due to excessive electric currents.

High output power amplifier

A radio-frequency heating apparatus includes a radio-frequency power generation unit (), variable phase shift units (to) that change a phase of a radio-frequency power generated by the radio-frequency power generation unit (), radio-frequency power units (to), and a control unit () that sets a frequency for the radio-frequency power generation unit () and a phase shift amount for the variable phase shift units (to). Backward power detection units in the radio-frequency power units (to) individually detect a reflected power and a through power at the frequency set for the radio-frequency power generation unit () by the control unit (), and the control unit () determines a frequency for the radio-frequency power generation unit () and a phase shift amount for the variable phase shift units (to) for heating the object, on the basis of the detected amplitude and phase of the reflected wave and the through wave.

A variable-frequency oscillator, a semiconductor power amplifierfor amplifying the output of the variable-frequency oscillator; a radiatorfor radiating an electromagnetic wave for heating based on the output of the semiconductor power amplifier; a reflected wave monitoring circuitfor detecting a reflected wave of the electromagnetic wave for heating; and a controllerfor controlling the oscillation frequency of the variable-frequency oscillatorare provided. The controllerchanges the oscillation frequencies of the variable-frequency oscillatordiscontinuously, thereby getting a frequency-hopping spread-spectrum radiation done by the radiator. The electromagnetic wave radiated by the radiatorirradiates an objectto be heated (which is usually food) inside a heating chamber, thereby heating the object.

Spread-spectrum high-frequency heating device

A digital television broadcast receiving section () of a mobile telephone terminal includes an antenna (), a notch filter (), a low-pass filter (LPF) (), a low noise amplifier (LNA) (), a receiving IC (), a control section (), and an input section (). A passband for digital television broadcast is divided into several parts. The control section () switches a characteristic of each of the notch filter () and the LPF () so as to combine filters appropriate for a low-band channel or a high-band channel. Thus, frequencies in a mobile telephone transmission frequency band of the mobile telephone terminal, and frequencies in a band of other systems, the frequencies in these band being interfering waves, are largely attenuated, and at the same time, frequencies in the passband which is a frequency band for digital television broadcast are allowed to pass with low loss.

High-frequency filter

A high frequency filter includes an inductor, a serial resonance circuit including an inductor and capacitors, a serial resonance circuit including an inductor and capacitors, and a varactor diode connected between a connection point between the capacitor and the capacitor and a connection point between the capacitor and the capacitor. A controller simultaneously changes two attenuation pole frequencies of the filter device by changing a capacitance of the varactor diode.

Growing community of inventors

Shiga, Japan

Toshiyuki Okajima