Abstract: The ferritic stainless steel sheet involves a problem that the ridging is likely to generate at the forming step, such as the deep drawing step. The ridging is believed to be caused by a band structure in the hot rolled band, which structure exerting an influence on the formability of a cold rolled sheet. The ridging is prevented in the present invention by means of the combination of the three technical measures: incorporating aluminum into a ferritic stainless steel; heating a slab to a low temperature of 1200.degree. C. or less; and, carrying out a drastic hot rolling of at least one pass with the draft of 20%/pass or more. As a result of these technical measures, the structure of a hot rolled band is made and uniform and thus both the formability and anti-ridging property are enhanced.

Abstract: A microwave oven with a rotary antenna for feeding electromagnetic waves to a heating chamber. The antenna has a first antenna portion and a second antenna portion which extend in mutually opposite directions and substantially at right angles to a rotary shaft portion, the length of the first antenna portion being greater than that of the second antenna by approximately one quarter of the wavelength of the electromagnetic waves used and the free end of the first antenna portion being bent substantially at right angles thereto for a length not exceeding one quarter of the wavelength to thereby ensure a uniform electric field distribution within the heating chamber.

Abstract: The present invention is a high frequency heating apparatus which has a high frequency oscillator for radiating high frequency energy when energized by a high voltage, a waveguide for propagating the high frequency energy from the high frequency oscillator to a heating cavity or heating chamber of the apparatus in which an object to be heated is placed, and an electric wave radiating member provided between and extending into the waveguide and the heating chamber. The electric wave radiating member both couples, through electric waves, the waveguide with the heating chamber and also radiates the high frequency energy into the heating chamber for uniform heat distribution within the heating chamber.

Abstract: A microwave oven comprising an enclosure including a wall member defining an opening for providing access to a heating cavity, the wall member having a continuous uninterrupted planar surface portion substantially surrounding the access opening. A door is provided for closing the opening in the wall member, the door having a continuous uninterrupted planar surface portion positioned, when the door is closed, opposite and substantially parallel to the planar surface portion of the wall member. An energy seal comprising walls defining a sealing cavity is formed in either the wall member or the door, the sealing cavity extending in a longitudinal direction to substantially surround the continuous uninterrupted planar surface portion of the member in which it is located. A segmented partition wall is interposed between the walls of the sealing cavity thereby separating it into two longitudinally extending spaces.

Abstract: A ferritic stainless steel having excellent formability, for example, in a deep drawing procedure, contains 0.04 to 0.1 weight % of C, 1.0 weight % or less of Si, 0.75 weight % or less of Mn, 10 to 30 weight % of Cr, 0.5 weight % or less of Ni, 0.025 weight % or les of N, 2 to 30 ppm of boron, and optionally, 0.005 to 0.4 weight % of an additional alloy component consisting of Al and, further optionally, a further additional alloy component consisting of at least one member selected from 0.005 to 0.6 weight % of Ti, 0.005 to 0.4 weight % of Nb, V, and Zr, 0.02 to 0.50 weight % of Cu, and 0.05 weight % or less of Ca and Ce, the sum of the contents of C and N being 0.0502 weight % or more.

Abstract: A microwave leakage-preventive device for use with a high frequency heating appliance for dielectric heating of an object by high frequency energy has a choke attenuator installed in a door for attenuation of microwaves, the choke attenuator being of the type adapted to enter an oven cavity when the door is closed. A portion of the choke attenuator is received in a recess formed within the door body, so that the choke attenuator entering the oven cavity is made smaller by an amount corresponding to the dimension thereof received in the door body. The width of the recess formed within the door body is made larger than the width of the choke attenuator entering the oven cavity, thereby providing a small-thickness door which is superior in microwave leakage prevention.

Abstract: A high frequency heating appliance which includes a magnetron, which is used as a high frequency oscillator, and which is directly mounted in a heating chamber and which further includes a stirrer fan for ensuring a uniform electric field distribution of high frequency electromagnetic radiation in the chamber; the fan is mounted coaxially with an antenna for the magnetron; the stirrer fan is provided with a vertical metallic segment for high frequency impedance matching and the vertical metallic segment has a horizontal metallic subsegment located on its end which is oriented so as to be substantially at right angles with the vertical metallic segment for providing a sufficient capacitive coupling between the wall of the heating chamber and the horizontal metallic subsegment with an adequate gap being secured from the heating chamber wall supporting the magnetron. The above-noted construction ensures an improved efficiency and improved distribution of the high frequency output of the magnetron.

Abstract: An austenitic stainless steel of a specific composition is cast into a slab and subjected to hot rolling, descaling, cold rolling without a step of preliminary annealing, and annealing.The steel sheet or strip thus obtained is of excellent quality with a satisfactorily low degree of anisotropy.

Abstract: In a process for the production of cold rolled ferritic stainless steel sheets or strips, a hot rolled strips has been annealed by a long time batchwise annealing and cold rolling and recrystallization annealing have been repeated usually twice. In the present invention, a hot rolled steel strip of an Al-containing ferritic stainless steel is heated by continuous annealing to a temperature of from 850.degree. to 1100.degree. C., AlN (aluminum nitride) is precipitated in the dispersed state and then cooling the strip to a temperature of 700.degree. to 900.degree. C., performing subsequent cooling to a level not higher than 200.degree. C. at such a cooling rate that a chromium depletion layer, which causes a gold dust defect, is not formed around the chromium carbonitride. Single cold rolling and recrystallization annealing are carried out in combination until the thickness is reduced to the gauge thickness.

Abstract: A microwave heating apparatus has a heating chamber in which an object is to be heated both dielectrically by microwave and by radiant energy. A microwave generator for generating microwaves is disposed above the heating chamber, and a radiant energy heater is located within the heating chamber. A rectangular wave guide extends between the generator and an opening in the chamber for guiding the microwaves generated by the generator into the heating chamber from above, the wave guide being bent generally in the shape of the letter Z and the portion of the wave guide other than the portion adjacent the opening into said heating chamber being spaced from the walls of the heating chamber. Thermal insulation is provided between the chamber and the portion of the wave guide spaced from the walls of the chamber.

Abstract: An improved choke seal arrangement, in a microwave oven, in which a slit structure is provided to prevent leakage of microwave energy around the periphery of the door. The slit structure, which has been provided in one of the walls defining the choke cavity in the prior art choke seal arrangement, is provided in a door wall portion spaced apart from the choke cavity so as to facilitate mechanical formation of the choke cavity and also to prevent deformation of the choke cavity wall during use. The choke seal arrangement permits the gap between the wall of the choke cavity and the confronting inner wall of the heating chamber to be smaller than hitherto, and the microwave seal performance further improved.

Abstract: There is disclosed an energy feeding device for installation in a high frequency heating appliance which includes a heating chamber, a high frequency oscillator for supplying a high frequency energy to the heating chamber, a waveguide for transmitting the high frequency electromagnetic wave generated from the high frequency oscillator, and a rotary antenna for radiating the high frequency electromagnetic wave so transmitted by the waveguide into the heating chamber. The rotary antenna has a revolving drive shaft, made of a material with a low dielectric loss and is connected to a drive source, a metal pipe which is connected to the revolving drive shaft at its socket end. The socket end of the metal pipe is expanded and rounded off, thereby substantially preventing sparking under light load.

Abstract: The present invention is a microwave oven having a rotary antenna with a substantially tubular L-shaped configuration from which microwaves are radiated into a heating cavity. This antenna is constituted by a first antenna portion, which extends from and is perpendicularly to a wall of the heating cavity in the microwave oven and has a length substantially equal to a quarter of the wavelength, and a second antenna portion which extends parallel to the wall and has a length substantially equal to half the wavelength so as to distribute the microwaves evenly inside the heating cavity.

Abstract: A microwave heating apparatus with a heating chamber, a high frequency oscillator, and a wave guide between the oscillator and the chamber has a rotatable antenna coupling the wave guide with the heating chamber for distributing high frequency radiation in the chamber. The rotatable antenna has an inner end extending into the wave guide and which is rotatably mounted therein, a first magnet is provided in the inner end of the rotatable antenna, and an antenna drive motor located outside the wave guide has a second magnet in spaced opposed relation to the first magnet and forming a magnetic coupling therewith.

Abstract: A microwave heating apparatus has a body with a front wall, and a heating chamber within the body for holding an object to be heated. A microwave source is provided for generating microwaves, and a wave guide is connected between the microwave source and a microwave inlet for guiding the microwaves from the microwave source to the heating chamber. A radiant energy heater is disposed within the heating chamber for heating the object to be heated by radiant energy, and a power box is positioned above the chamber and housing the microwave source and the high voltage circuit components therefor. A microwave source cooling fan is provided in the power box, and thermal insulation covers the walls of the heating chamber, the upper surface of the thermal insulation on the top of the chamber and the bottom surface of the power box being spaced to provide a cooling conduit.

Abstract: A heating appliance such as a stove which has a high frequency and resistance heater therein. A high frequency oscillator supplies frequency radiation energy through a waveguide extending to a energy feeding port in the heating chamber, and a rotary antenna extends through the energy feeding port for directing the high frequency energy into the heating chamber. A motor rotates the antenna, a heater of a type other than a high frequency heater, such as a resistance heater, is in the heating chamber substantially parallel with the wall of the heating chamber in which the energy feeding port is positioned.

Abstract: A microwave oven which is provided with an electric heating arrangement for surface browning of an object to be heated which includes a heater portion having a heater surrounded by a sheath and a power supplying base portion enclosed in a metallic cover and having power supplying electrodes for the heater portion, and power feeding section having choke structure for preventing leakage of high frequency waves which is provided in one of the walls defining a heating cavity so as to receive the power supplying base portion in an opening formed in the choke structure, while the sheath is so connected to the metallic cover as to establish good electrical conduction therebetween, so that sealing of high frequency waves is achieved between the heater and choke structure.

Abstract: Microwave heating apparatus employing at least one surface waveguide which is provided in a lower portion of the apparatus below an article to be heated receives microwave output, directly or via a tubular waveguide, from an oscillator means, and acts to concentrate microwave energy in a specific region of the apparatus, whereby heating is rendered more efficient and unevenness of heating in the vertical plane is avoided. For improved evenness of heating in the horizontal plane the surface waveguide may be rotated either by separate drive means or by air supplied to cool the oscillator means, or the article to be heated may be rotated or moved reciprocally while the surface waveguide is moving or is stationary. The improved concentration of microwave energy permits greater economy, and offers a particular advantage for producing highly a baked or hardened outer surface without overheating of other portions of an article to be heated.

Abstract: A welding material for low temperature steels composed of a core wire or coated core wire, the wire containing 0.05 to 0.5% carbon, 0.15 to 0.75% silicon, 20 to 50% manganese, 4 to 17% chromium, 0.005 to 0.5% nitrogen and more than 0.5 to 10% molybdenum, with the balance being iron and unavoidable impurities.

Abstract: There is disclosed a magnetron power supply means which avoids use of bulky components and which has a frequency converter for drive of a magnetron at a frequency higher than that of a commercial power source. Feedback is supplied to the converter which in response maintains output within a specific range, which may be adjustable, whereby the power supply to the magnetron, and hence the output thereof are regulated.