Abstract: A power transmission joint comprises a pair of rotational members each having a rotation axis and arranged so as to be axially spaced from each other. A guide pin is disposed between the pair of rotational members and has an end portion thereof rotatably and swingably engaged with opposite end portions of the rotational members at rotation axes, respectively. A pair of drive pins are arranged symmetrically with respect to and in parallel to an axis of the guide pin and each is engaged with the opposite ends of the rotational members so as to transmit torque while allowing the drive pins to slide in a radial direction on the rotational members, swing and axially slide. A member is disposed between the pair of rotational members and rigidly ties the guide pin and the drive pins to keep a prescribed fixed relation therebetween.

Abstract: A surface, of an inner sleeve of a combustion apparatus for a gas turbine, which is subjected to a flame radiation heat is coated with a ceramic coating. A coating which is superior in high temperature corrosion resistant characteristics to a metal material forming the inner sleeve is provided on the opposite surface of the inner sleeve. Thus, heat transferred to the inner sleeve by the radiation from the flame is shielded by the ceramic coating. A formation of oxides on the coating of the corrosion resistant metal material formed on the opposite surface of the sleeve is prevented. A heat release through the surface from the metal material forming the inner sleeve is enhanced, whereby a thermal stress generated in the inner sleeve is suppressed to thereby prevent a generation of a cracks.

Abstract: The present invention is to extrude helical internal gears and helical gears by pushing materials processed to any type of blank into a die unit successively by use of a punch, i.e., by passing the materials once through the die unit. The invention is directed to a die unit comprising an outer contour restraining container into which metal material blanks each having a central bore are to be inserted, a die placed contiguously below the container, these container and die being arranged to be circumferentially rotatable relative to each other, and upper and lower mandrels disposed inside the container and the die in alignment with their axes, respectively, and interconnected for being circumferentially rotatable relative to each other, the metal materials being successively pushed into gaps between the upper mandrel and the container and between the lower mandrel and the die by means of a punch to mold helical internal gears.

Abstract: A wear-resistant metal member comprises a surface that has a sprayed layer consisting essentially of, by weight, 2 to 10% C, 18 to 60% Cr, 0.3 to 20% V, 25% or less Mo, 25% or less W, 10% or less Nb, 10% or less Ti, 10% or less Zr, 10% or less Hf and the balance being Fe in a proportion of 20% or greater. The sprayed layer has a martensite-phase matrix containing carbide particles, nitride particles or carbonitride particles. In addition, the member of the present invention is produced by the steps of: plasma-spraying the above-described metal in a reduced pressure atmosphere; and quenching the thus-sprayed metal layer from a predetermined temperature to form a materisite phase in that layer. In addition, the sprayed metal layer may be subjected to carburizing, nitriding or carbonitriding to form a carburized, nitrided or carbonitrided layer in the sprayed metal layer.

Abstract: A gas sensor includes a pair of electrodes printed on an electrically insulating substrate, a sensitive layer deposited on tip portions of the electrodes and a part of the substrate adjacent to the tip portions and bridging the space between the electrodes at the tip portion, and a protective film deposited on the electrodes and a part of the substrate adjacent to the tip portion so that a part of each electrode covered with the sensitive layer is free of the protective film. The sensitive layer is formed by depositing titanium oxide by plasma spraying on the substrate, and then heat-treating the deposited titanium oxide, so as to provide a diffusion reactive layer between the sensitive layer and the substrate and to form fine grooves on the surface of the sensitive layer.

Abstract: Gas sensor which is constructed of an electrically insulating base, electrodes formed on said base, and a gas sensitive film formed on the surface of said base at a portion where it detects a gas to be sensed, e.g., an oxygen gas. The gas sensor of the present invention is characterized in that the gas sensitive film is a thermal-sprayed film which is made of an oxide having a perovskite structure. The thermal-sprayed film has its surface formed with fine cracks to have its effective surface area increased so that the response is speeded up. Moreover, the thermal spraying process is so effected during the formation of the oxide film that an impurity to adversely affect the reliability may be avoided from being mixed.The gas sensor may have said gas sensitive film coated with a ceramic material so that is performance may be further improved while protecting the gas sensitive film. Furthermore, it is also effective to add another sensor with the electrically insulating base being commonly used.

Abstract: A gas sensor is described which includes a layer of a sensitive material formed on an electric insulating substrate and spaced electrodes electrically connected to the layer. The layer is formed of a porous film of a uniform mixture which contains a p-type compound oxide semiconductor with a perovskite type of crystal structure as the major ingredient and one or more of vanadium, niobium, tantalum and/or compounds thereof as minor ingredients. The minor ingredients are contained in the layer in an amount of 0.01 to 5% by weight, based on the weight of the p-type compound oxide semiconductor, and are incorporated into the layer by diffusing them into the layer. The gas sensor exhibits a small change with time and a reduced tailing effect attendant on variations in the gas combustion. With this, it is possible to effect measurements, detection and control with a high reliability.

Abstract: A gaseous compound of a metal species or a semi-metal species is reacted with another gaseous substance capable of reacting with the gaseous compound of the metal or semi-metal species under a total pressure of not more than 10 Torr, where the partial pressure of the gaseous compound is not more than that of the gaseous substance, the reacting being carried out by the glow discharge generated between an electroconductive workpiece connected to a cathode, at least one secondary cathode provided at a position near enough to the workpiece to generate interactions of glow discharge between at least selected portions of the workpiece and the at least one secondary cathode, and an anode, thereby coating the at least selected portions of the workpiece with the resulting reaction product containing the metal or semi-metal species.

Abstract: A glow discharge surface treatment process wherein only the selected portions of a workpiece adjacent to or surrounded by the associated secondary electrodes are surface-treated so as to provide different treatments on the workpiece according to the position of the secondary electrodes. The each secondary electrode is provided close to at least a portion of the workpiece, and the workpiece and the associated secondary electrode are both connected to the cathode. When a voltage is applied between the cathode and the wall of the container in the treatment apparatus which forms the anode, mutual interference effect (which is referred to as a hollow cathode effect) of negative glow discharges is established between the workpiece and the associated secondary electrode so as to accelerate the heat treatment for the selected portion of the workpiece surrounded by the secondary electrode. The gas pressure in the container is varied to control the hollow cathode effect.

Abstract: In a method of joining two metal members by forming an annular groove at least on one of the two metal members to be joined and causing part of the material of the metal member to flow into the annular groove by plastic deformation to form a joint, at least one annular angled member is formed in the annular groove. The annular angled member extending the entire periphery of the annular groove is substantially triangular in axial cross-sectional shape. The joint has increased strength and can be formed with reduced pressure.

Abstract: Guiding drums for a magnetic tape scanning assembly for use in a video tape recorder and playback apparatus are made of a specific aluminum-silicon alloy consisting essentially of 8 to 15% by weight of silicon, 1 to 4% by weight of copper, 0.05 to 0.6% by weight of magnesium, and the balance being aluminum. A mean grain size of silicon crystal in eutectic structure is controlled to be 5 .mu.m or less. The drums are provided with a diagonal or helical guiding path on the peripheries thereof in which there are formed on the guiding path generally continuous, fine machining lines having a roughness (H max) of 1 to 6 .mu.m, preferably 2 to 5 .mu.m, in a direction parallel with sliding travel of a magnetic tape.

Abstract: An aluminum alloy consisting essentially of 8 to 15% by weight of silicon, 0.05 to 0.7% by weight of magnesium, 1 to 4.5% by weight of copper, the balance being aluminum, wherein a silicon crystal in eutectic structure crystallized out in an aluminum matrix has a mean grain size not larger than 5 microns and intermetallic compounds of magnesium and copper are finely precipitated in the matrix as age-hardening elements for the matrix, and the alloy has at least 40 kg/mm.sup.2 tensile strength and at least 10% elongation, good antiwearing and excellent workability.The disclosure is also concerned with a method of making the above-mentioned aluminum alloy.