Abstract: A magnetic fluid composition comprising a less volatile organic solvent as a dispersing medium, a dispersing agent having oleophilic groups exhibiting an affinity therewith, fine ferromagnetic particles coated at the surface thereof with the dispersing agent and dispersed in the less volatile organic solvent and a fluorocarbon surface active material having an organophobic portion and an organophilic portion together in a unitary molecular structure. The magnetic fluid is prepared by the steps of adding the low boiling organic solvent and the dispersant having oleophilic groups to fine ferromagnetic particles to obtain an intermediate medium, separating the fine particles of poor dispersibility from the intermediate medium and, then adding the less volatile organic solvent and heating the resulting material to evaporate the low boiling organic solvent thereby obtaining a magnetic fluid and, further, adding the fluorocarbon surface active material to the magnetic fluid.

Abstract: A rolling bearing in which a bearing ring and/or a rolling element comprises an alloy steel wherein the hardness of a surface layer over a thickness corresponding to greater than 2% of a mean diameter of a rolling element is equal to or greater than 60 HRC and the hardness at least of the raceway surface or the rolling contact surface is equal to or greater than 64 and equal to or less than 69 HRC, and carbides of equal to or greater than 6 .mu.m converted as the diameter of a circle are not contained in a range from the raceway surface of the rolling contact surface as far as the depth corresponding to 2% of the mean diameter of the rolling element.

Abstract: A fault detection device for an occupant protective system for use in an automotive vehicle, which has a plurality of squibs connected in parallel with each other. A common signal is generated for actuating the squibs to operate the system when the vehicle undergoes deceleration in excess of a predetermined value. A squib circuit has the squibs, at least one resistance connected to the squibs in such a manner that a slight amount of current flows through the squibs, and a unilateral conductive element connected to the squibs and the resistance in such a manner that the slight amount of current flows through the squibs in a predetermined single direction. A fault detection circuit detects a fault in any of the squibs based on a potential at a predetermined location in the squib circuit.

Abstract: A dynamic pressure bearing device includes a sleeve and a shaft member which is rotatably fitted into the sleeve. The sleeve is made of an aluminum alloy containing a carbon fiber and has a radial bearing surface formed in an inner peripheral surface and a thrust bearing surface formed in a lower end surface. The shaft member includes a base portion having a thrust receiving surface formed on an upper surface, and a shaft portion extending upright from the base portion and having a radial receiving surface formed on an outer peripheral surface. A first dynamic pressure generating groove is formed in at least one of the radial bearing surface and the radial receiving surface, and a second dynamic pressure generating groove is formed in at least one of the thrust bearing surface and the thrust receiving surface. The shaft member including the shaft portion and the base portion is molded from a synthetic resin as a unitary body.

Abstract: A linear movement guide bearing including a main body accommodating a pair of side by side roller trains is linearly movable in an axial direction along a raceway surface through rolling of the roller trains. A pair of side protection covers formed of metal plates are attached to the main body to respectively cover substantially the whole lateral sides of the main body and end caps which are fixed to axial opposite ends of the main body. A pair of end protection covers formed of metal plates are respectively fixed to outer end surfaces of the end caps to protect the end caps. The side and end protection covers insure the mechanical strength of the guide bearing against external impacts. Seal members are respectively attached to lower edges of the side and end protection covers to seal clearances between the lower edges of the protection covers and the raceway surface.

Abstract: A nut block, which is driven by a feed screw shaft and which is movable axially within a guide rail having a U-shaped cross section, is provided with extending portions extending laterally from both upper side portions thereof. The extending portions are positioned near the upper surfaces of both side walls of the guide rail to cover these upper surfaces. A flexible seal plate of a magnetic material is provided to cover the whole length of the opening in the guide rail. The seal plate forms an expanded portion expanding upwardly at a portion corresponding to the nut block with the movement of the nut block. The seal plate has opposite ends respectively fixed to opposite axial ends of the guide rail. Both edge portions of the seal plate are attracted to rubber magnets mounted on the upper surfaces of the side walls of the guide rail.

Abstract: A rolling bearing comprise a bearing ring having inner and outer rings, and rolling elements. At least one of the inner and outer rings and the rolling elements is formed of a sintered alloy steel and has pores and carbides present therein. The largest one of the pores has a diameter equal to or smaller than 3 .mu.m in terms of a diameter assued if the largest pore were converted to a spherical shape. The largest one of the carbides has a diameter equal to or smaller than 12 .mu.m in terms of a diameter assumed if the largest carbide were converted to a spherical shape. The at least one of the inner and outer rings and the rolling elements has hardness higher than 64 and lower than 69 in terms of HRC.

Abstract: A linear guide apparatus includes an axially extending guide rail having ball rolling grooves formed in both side surfaces, and a slider movably straddling the guide rail and having ball rolling grooves formed in inner surfaces of both side walls. At least one of a clearance between an upper surface of the guide rail and a lower surface of the slider and a clearance between a side surface of the guide rail and an inner side surface of the slider is set smaller than the amount of displacement caused by an elastic deformation of contact portions at which the ball is in contact with the groove surfaces of the ball rolling grooves of the guide rail and the slider when a load equal to a fundamental static rating load is applied to the slider.

Abstract: A clamp band has an inner end and an outer end. A first tool engaging portion to be engaged with one of paired clamping force application portions of a clamping tool, a first clamp portion and a projection adjacent to the first clamp portion are formed in sequence as viewed from a tip edge of the inner end. A second clamp portion to be engaged with the first clamp portion is formed near a tip edge of the outer end, and a second tool engaging portion to be engaged with the other clamping force application portion of the clamping tool is formed on the outer end at a position further from the tip edge. A distance between the first clamp portion and the projection and a distance between the second clamp portion and the tip edge of the second end are selected such that the tip edge of the second end is juxtaposed to an end edge of the projection when the first clamp portion is engaged with the second clamp portion.

Abstract: In a tripod type constant velocity joint a tripod is disposed within a cylindrical housing such that three equi-angularly spaced trunnions of the tripod are received within corresponding recesses of the housing. Each trunnion has a spherical roller mounted thereon through a plurality of rolling bearing members, and a cylindrical roller mounted on the spherical roller. An inner peripheral concave spherical surface of the cylindrical roller is in intimate sliding contact with an outer peripheral convex spherical surface of the spherical roller, and an outer cylindrical surface of the cylindrical roller is in rolling contact with the opposite side surfaces of the corresponding recess. The rolling bearing members, the spherical rollers, and the cylindrical rollers are disposed within a circle formed by linking the ends of the trunnions together.

Abstract: A through anchor suitable for use in a seat belt system is disclosed. In use, the through anchor is mounted by way of a through bore formed in a fixing member arranged on a side of a vehicle body. The through anchor comprises a metal plate, a fixing bolt, a resin covering and an internally-threaded member. The metal plate defines therein a through hole and a webbing slot. The fixing bolt has a head portion, a threaded portion and a base portion. The resin covering is molded as an integral member on a surface of the head portion of the fixing bolt and a surface of the metal plate. The internally-threaded member has a cylindrical portion and a flange portion extending radially and outwardly from the cylindrical portion.

Abstract: A roller type linear guide apparatus includes a guide rail having V-shaped roller rolling grooves, respectively formed in lateral side surfaces, and a slider having V-shaped bearing mounting grooves respectively formed in inner surfaces of both side walls. A roller bearing which is mounted to each of the V-shaped bearing mounting grooves of the slider includes a pair of roller rows, and each row of rollers circulate along an elliptic infinitely circulating path. Circulating planes respectively containing the elliptic infinitely circulating paths of the two roller rows of the roller bearing are inclined to intersect each other so that loaded rollers of one of the two roller rows roll on one inclined surface of the V-shaped roller rolling groove and loaded rollers of the other of the two roller rows roll on the other inclined surface of the V-shaped roller rolling groove of the guide rail.

Abstract: An overrun preventing device to prevent a slider from falling off of a guide rail is fixed to one end of the guide rail of a linear guide apparatus. The overrun preventing device includes a main body made of a metal plate having an inverted U-shaped cross section, and a slide plate. The main body has lift preventing plate portions formed by bending lower edges of both side walls of the main body inwardly at right angles so that the lift preventing plate portions are engaged with rolling member rolling grooves formed in both sides of the guide rail to prevent upward movement of the main body. The slide plate has a rectangular shape. One end of the slide plate is inserted between the main body and the upper surface of the guide rail so that the slide plate is expandable with respect to the main body depending on a fixing position of the slide plate on the guide rail.

Abstract: A linear movement guide bearing includes a guide rail and a slider straddling the guide rail for movement in an axial direction through rolling of balls interposed between the guide rail and the slider. A pair of under seals are attached to lower surfaces of the slider so that inner edges of the slide are slidably in contact with the side surfaces of the guide rail. Each under seal has elastic projection portions at axial opposite ends which protrude vertically toward the lower surface of the slider. Each elastic projection portion is formed by a forked elastic projection having two projection pieces whose free ends are expanded outwardly. Hook-like holding projections are formed on the free ends of the two projection pieces and protrude outwardly therefrom. The slider has vertical apertures formed in the lower surface for fitting the forked elastic projections thereinto and has through bores respectively formed orthogonal to the vertical apertures.

Abstract: A ferrofluid composition is defined by fine particles of ferromagnetic material, a liquid carrier for dispersing the ferromagnetic material and a surfactant or surfactants acting as a dispersant. The surfactant is required to have such relation to the carrier that the surfactant has, as its hydrophobic group portion, a structure equivalent to the carrier, and the carrier is selected to be either an alkylpolyphenyl ether oil, an alkylnaphthalene oil or both. By virtue of this structural feature, fine ferromagnetic particles are uniformly and stably dispersed throughout the carrier which has low viscosity and is thermally very stable.

Abstract: A rolling contact parts steel has C: 0.2-0.6 wt%; Si: 0.3-2.0 wt%; Cr: 0.5-2.5 wt%; Mn: 1.7 wt% or less; O: 12 ppm or less; and the balance of Fe and an inevitable impurity. The steel produces a fine carbide without the need for a separate heat treatment. The dimensioal stability at high temperature of the steel is superior. A rolling bearing has at least one of the races and the rolling element thereof made of the steel, the steel being carburized or carbonitrided, then quenched and then, finally, tempered. The one of the races and the rolling element will not soften at a high temperature.

Abstract: A rolling contact element steel has C: 0.2-0.6 wt %; Si: 0.5-2.0 wt %; Cr: 5.0-8.0 wt %; Mo: 3.0 wt % or less; Mn: 1.6 wt % or less; O: 12 ppm or less; and the balance of Fe and an inevitable impurity. A rolling bearing made of this steel will not soften even at high temperature. The dimensional stability at high temperature and wear-resistance of the steel are superior. The steel can produce a fine carbide without the need for a separate heat treatment. A rolling bearing has at least one of the races and the rolling element made of the steel, the steel being carburized or carbonitrided, then quenched and finally high-temperature tempered.

Abstract: An aqueous magnetic fluid composition comprising water as a dispersion medium and fine ferromagnetic particles as a dispersed phase, in which a coupling agent having a hydrophilic group and at least one hydrolyzable group is chemically bonded by way of the reaction product of the hydrolyzable group to the surface of the fine ferromagnetic particles. The magnetic fluid composition is prepared by way of obtaining an intermediate medium by chemically bonding the coupling agent by way of the hydrolysis product to the fine particles and separating fine particles of poor dispersibility and evaporating the composite product of the hydrolysis and at least a portion of water.

Abstract: Each of the pair of under seals which are respectively attached to the lower surfaces of the side walls of a slider includes an elongate core metallic plate and a rubber member secured to the core metallic plate and having a lip portion protruding inwardly from the inner edge of the core metallic plate. Each of the end caps attached to opposite ends of a slider main body is formed with an under seal holding groove in a joining surface of each leg portion of the end cap. The slider main body is formed with a stepped recess portion to accommodate the under seal in the lower surface of each side wall. The opposite ends of the under seal are fitted into and held in the under seal holding grooves of the end caps and the remainder of the under seal is accommodated in the stepped recess portion of the slider main body. The lip portion os the under seal is slidingly in contact with the lateral side of the guide rail to prevent dust from entering into the inside of the slider.

Abstract: A bearing device assembly includes a water pump shaft supported by a rolling bearing, and a .[.plulley.]. .Iadd.pulley .Iaddend.seat press fitted to one end of the water pump shaft. A recess or recesses in the form of a ring-shaped groove, a spiral-shaped groove, and a groove extending in the axial direction of the shaft, or the like are formed in at least one of the peripheral surface of the one end portion of the water pump shaft and the inner surface of the pulley seat. The recess prevents formation of an oil film on the fitting surface between the water pump shaft and the pulley seat at the time of press fitting the pulley seat, and also allows the remaining oil on the fitting surface to flow into the recess.