Abstract: A stationary induction apparatus for supplying and receiving high frequency power of several tens KHz, wherein a partition wall made of a non-magnetic metallic foil in a thickness less than 1/10 the depth of penetration in the using freqency for electromagnetic induction is provided so as to separate the supply side (primary side) from the receiver side (secondary side), so that the stationary induction apparatus is not hurt in its function as an induction apparatus, but can electromagnetically shield the primary side from the secondary side, and the secondary side of the boosting transformer of the magnetron is able to be placed within the shield casing, thus realizing a light, compact and inexpensive microwave generating device for use in an electronic oven.

Abstract: A cooking heating apparatus has a vapor sensor for sensing the state of heating of food in a heating chamber, thus performing automatic control of the heating operation. An auxiliary exhaust opening for allowing vapor from the heated food to be introduced to the vapor sensor is formed in a region where the flow of the vapor is not influenced by a main flow of air supplied into the heating chamber and flowing towards a main exhaust opening. The vapor sensor is disposed so as to be exposed to the vapor introduced through the auxiliary exhaust opening. The condition of the vapor is therefore sensed quickly without being influenced by the main flow of air.

Abstract: A high-frequency heating apparatus comprises a semiconductor power converter which is supplied with electric power from a commercial power supply, a radio wave radiation section which is energized by the semiconductor power converter, a control section which controls the operation of a semiconductor element of the semiconductor power converter, and a start control section which controls the operation of the control section at the start time of the high-frequency heating apparatus. The start control section controls the operation of the control section so that the radio wave output power from the radio wave radiation section at the start time of the high-frequency heating apparatus becomes greater than that in the steady operation state thereof, whereby optimization of the performance and price of the heating apparatus can be realized.

Abstract: A high frequency heating device includes a high frequency oscillator, a heating chamber for accommodating an object to be heated, and a cylindrical wave guide for coupling the high frequency oscillator to the heating chamber. The output antenna for the high frequency oscillator is disposed at an input end portion of the cylindrical wave guide and along the center axis of the wave guide. The heating chamber has a wall which is coupled to the cylindrical wave guide, the wall being positioned in an end plane of the cylindrical wave guide opposite to the output antenna. An arcuate slit is formed in the wall with the center of curvature of the slit being centered at the center axis of the cylindrical wave guide. This construction suppresses higher harmonics, and furthermore impedance matching and adjustment of the heating performance are facilitated.

Abstract: An arrangement comprises a hinge (4) positioned in the lowest region of the front surface at a front opening (2) in a heating chamber (1), a door (3) swingable around the axis of the hinge (4), and a weight detecting section (11) provided on the hinge (4) of the door (3) for detecting the weight of a heating load (20) by converting deformation produced by the load into an electric signal, wherein the weight of the heating load (20) placed on the door (3) when the latter is opened is detected by the weight detecting section (11). Accurate weight detection is possible no matter where the heating load (20) may be placed on the door (3). Tare subtraction weight detection is possible by utilizing a microcomputer. Further, it is also possible to automatically control heating operation in association with weight detection.

Abstract: An electromagnetic energy seal for use in a microwave oven comprises a first sealing cavity formed along at least one of a peripheral edge portion of an entrance opening of a heating chamber and a portion of a door for opening and closing the entrance opening of the heating chamber which is opposite to the peripheral edge portion of the entrance opening of the heating chamber, and a second sealing cavity disposed in the opening of the first sealing cavity. These first and second sealing cavities have a simple structure which produces high shield effects against the fundamental microwave frequency and the higher harmonic microwave frequency components thereof, respectively, and the adjustment and optimization of the choking frequency characteristics of the cavities can be made easy.

Abstract: A turntable drive mechanism for a microwave oven having an oven-defining structure having a bottom wall and a hingedly supported door for selectively closing and opening an access opening leading into the interior of the oven-defining structure. The turntable drive mechanism has a turntable assembly removably positioned on the bottom wall for rotation about its own center through a plurality of rollers situated between the turntable assembly and the bottom wall, and a plurality of magnets. Cooperating with these magnets carried by the turntable assembly are magnets carried by a rotary carriage driven by a drive unit in one direction and situated below the bottom wall and externally of the oven-defining structure. Rotation of the turntable assembly is induced by rotation of the rotary carriage by the effect of magnetic forces of attraction developed through the bottom wall between the magnets on the turntable assembly and the magnets on the rotary carriage.