Abstract: A resistive heating element 30 has a higher molybdenum carbide content in a central portion 35 than in a peripheral portion 34. Since molybdenum carbides have a low temperature coefficient of resistance compared to molybdenum, the amount of heat generated in the central portion 35 of the resistive heating element 30 does not increase as much as in the peripheral portion 34 even when the temperature is increased, and the increase in difference in temperature between the peripheral portion 34 and the central portion 35 can be suppressed. In other words, generation of hot spots near the center can be suppressed and a good uniform heating property in a wide range of operation temperatures can be obtained.

Abstract: A magnetic element for multi-phase is composed by burying a plurality of coils in a composite magnetic material such that a negative coupling of magnetic fluxes or a positive coupling of magnetic fluxes exists between at least two coils. This structure more miniaturizes inductors, or choke coils as the multi-phase magnetic element suitably used for application of a large current to many kinds of electronic equipment. Such multi-phase magnetic element has an excellent ripple current property.

Abstract: A temperature sensor for detecting a temperature of, for example, an exhaust gas of a vehicle is manufactured by inserting a thermistor element into a bottomed metal tube while filling an inside of the metal tube with a filler material, preferably of silicone oil, to reduce a sliding resistance between the thermistor element and the metal tube as an integral temperature sensing structure which is then mounted in a housing.

Abstract: A windbreak provided along a side of a tray prevents insulators located close to an entrance of a furnace from being directly cooled by the air coming into the furnace. All of the insulators mounted on the tray can be uniformly cooled when conveyed out of the furnace after finishing a sintering operation. A resistance value of the electric resistor in an insulator located close to the entrance is substantially equalized with a resistance value of the electric resistor in another insulator located far from the entrance.

Abstract: A windbreak provided along a side of a tray prevents insulators located close to an entrance of a furnace from being directly cooled by the air coming into the furnace. All of the insulators mounted on the tray can be uniformly cooled when conveyed out of the furnace after finishing a sintering operation. A resistance value of the electric resistor in an insulator located close to the entrance is substantially equalized with a resistance value of the electric resistor in another insulator located far from the entrance.

Abstract: A coiled heating element is manufactured by providing a coiled element of bare resistance wire in which the coil pitch is not greater than twice the cross-sectional dimension of the wire. The element is stretched by an amount permitting recovery to its original configuration and an electrically insulating particulate material is applied to the stretched element. The stretched element is then allowed to return towards its original configuration thus trapping particulate material between adjacent coils of the element and the element is heated so as to oxidize the surface of the wire.

Abstract: A method for producing negative temperature coefficient thermistor units, comprising the steps of forming a pair of green sheets of insulating ceramic material, stacking the green sheets interposing therebetween in predetermined areas a layer of paste for thermistor elements; providing for each thermistor unit a coating of paste to be formed into internal electrodes; cutting the stacked sheets into individual thermistor units; co-firing the thermistor units whereby the thermistor element is enclosed in an envelope of sintered ceramic material or sandwiched between two layers of sintered ceramic material. A pair of external electrodes is then provided on each thermistor unit.

Abstract: High temperature BN-insulated heaters for use as fuel pin simulators in reactor thermal hydraulic test facility studies comprise a cylindrical housing and a concentric heating element disposed within the housing and spaced apart from the housing to define an annular region therebetween. The annular region contains BN for providing electrical resistance and thermal conductivity between the housing and the heating element. The fabrication method of this invention comprises the steps of cold pressing BN powder at a pressure of 20 to 80,000 psig and a dwell time of at least 0.1-3 seconds to provide hollow cylindrical preforms of suitable dimensions for insertion into the annular region, the BN powder having a tap density of about 0.6-1.1 g/cm.sup.3 and an orientation ratio of at least about 100/3.5. The preforms are inserted into the annular region and crushed in place.

Abstract: A mineral insulated heating cable and a method of making same wherein the cable has the characteristic that for a given supply voltage the heat generated per unit length of the cable is substantially unaffected by the total length of the cable. The mineral insulated heating cable comprises at least two metallic conductors, a metallic protective sheath, a body of compacted mineral insulating material filling the sheath and spacing the conductors from one another and embedded in the compacted mineral insulating material and contacting each of the two said conductors throughout their lengths, at least one resistance element in the form of a thin layer consisting predominantly of resistive material.