Abstract: A gear comprised of a tooth surface and a hard carbon film formed on at least a part of the tooth surface. When the gear is used in lubricant including a specific component, a friction of a tooth surface of the gear is largely decreased, and therefore the gear performs an excellent power transmission efficiency. Further, when the gear is employed in a planetary gear mechanism or speed reducing mechanism which has a plurality of meshing portions of gears, the power transmission efficiency of the mechanism is also improved.

Abstract: A slidably movable member such as an adjusting shim used in a valve operating mechanism of an internal combustion engine of an automotive vehicle. The slidably movable member is used in contact with lubricating oil and comprises a substrate. A hard carbon-based film is coated on a surface of the substrate. The hard carbon-based film has a surface section which contains at least one of nitrogen and oxygen in an amount ranging from 0.5 to 30 at % and/or hydrogen in an amount of not more than 10 at %.

Abstract: A piston for an internal combustion engine of an automotive vehicle. The piston has a piston ring and a piston skirt section each of which has a sliding section in slidable contact with a cylinder bore section of a cylinder block in presence of a lubricating oil. The cylinder bore section is formed of eutectic or hyper-eutectic aluminum alloy. Additionally, a hard carbon thin film is coated on the sliding section of the piston and contains hydrogen atom in an amount of not more than 1 atomic %. Here, the lubricating oil contains at least one selected from the group consisting of ashless fatty acid ester friction modifier, ashless aliphatic amine friction modifier, polybutenyl succinimide, derivative of polybutenyl succinimide, zinc dithiophosphate, and derivative of zinc dithiophosphate.

Abstract: An engine piston-pin sliding structure includes a piston pin slidably engaged into a pin boss of an engine piston and having a base and a hard carbon coating formed on the base so as to define a sliding surface slidable over a bearing surface of the pin boss and a lubricant interposed between the sliding surface of the piston pin and the bearing surface of the pin boss. The hard carbon coating contains 25 atomic % or less of hydrogen, and the lubricant contains at least one of an ashless fatty-ester friction modifier and an ashless aliphatic-amine friction modifier.

Abstract: A low friction sliding combination of a cam and a cam follower which are in slidable contact with each other in presence of a lubricating oil. The cam follower includes a cylindrical and hollow outer roller having an outer peripheral surface in slidable contact with the cam. A fixed pin is coaxially disposed inside the outer roller and rotatably movable relative to the outer roller. A diamond-like carbon material is coated on a sliding surface of at least one of the outer roller and the fixed pin. The lubricating oil contains at least one of ashless fatty acid ester friction modifier and ashless aliphatic amine friction modifier.

Abstract: A low-friction sliding mechanism of the present invention comprises first and second sliding members slidable relative to each other at sliding surfaces thereof and a lubricant being applied to the sliding surfaces of the first and second sliding members. The first and second members are made of a diamond-like carbon material and an iron-based material, respectively, and the lubricant comprises a base oil and at least one of an ashless fatty-ester friction modifier and an ashless aliphatic-amine friction modifier.

Abstract: A sliding structure including first and second sliding elements made of metal and including first and second sliding surfaces relatively slidable via a lubricating oil film therebetween, in which at least one of the first and second sliding surfaces having a microscopic surface structure including a base portion, dimples inward recessed from the base portion and separated from one another, and a peripheral portion defining the opening area of each of the dimples and extending along a periphery of each of the dimples. A ratio of a sum of opening areas of the dimples to an area of the at least one of the first and second surfaces is in a range of 5% to 60%. The peripheral portion has a height smaller than a thickness of the lubricating oil film.

Abstract: A rare earth magnet to be used in a motor. The rare earth magnet comprises rare earth magnet particles.

Abstract: A Nd—Fe—B type anisotropic exchange spring magnet is produced by a method of obtaining powder of a Nd—Fe—B type rare earth magnet alloy which comprises hard magnetic phases and soft magnetic phases wherein a minimum width of the soft magnetic phases is smaller than or equal to 1 &mgr;m and a minimum distance between the soft magnetic phases is greater than or equal to 0.1 &mgr;m, obtaining a compressed powder body by compressing the powder, and obtaining the Nd—Fe—B type anisotropic exchange spring magnet by sintering the compressed powder body using a discharge plasma sintering unit.

Abstract: A sliding structure for a reciprocating internal combustion engine, including sliding elements relatively slidable via lubricating oil therebetween, the sliding elements including sliding surfaces opposed to each other and lubricated with a laminar flow of the lubricating oil. The sliding surfaces each have base surfaces and microscopic dimples or grooves which are so constructed as to prevent reduction of flow resistance to the lubricating oil passing through a clearance between the sliding surfaces and assure a lubricating oil film thickness required for reducing friction loss between the sliding elements.

Abstract: A rotary assembly for traction drives, including a plurality of rolling elements having a rotation axis and traction contact surfaces around the rotation axis and associating with each other to transmit a motive power between the rolling elements via a traction oil film formed between the traction contact surfaces, in which at least one of the traction contact surfaces has a microstructure with irregularities which sizes are larger than a thickness of the traction oil film. The process for the traction contact surface is also disclosed.

Abstract: A low friction sliding element for reciprocating engine parts, including a sliding contact surface that is in sliding contact with a counterpart during relative sliding motion of the sliding element and the counterpart. The sliding contact surface has microscopic recesses and plateaus interrupted by the recesses. The recesses have depths regularly varying in a sliding direction of the sliding element.

Abstract: A low-friction sliding mechanism includes first and second sliding members having respective sliding surfaces slidable relative to each other and a lubricant applied to the sliding surfaces of the first and second sliding members. At least the sliding surface of the first sliding member is made of a diamond-like carbon material, and at least the sliding surface of the second sliding member is made of either an aluminum-based alloy material, a magnesium-based alloy material or a diamond-like carbon material. The lubricant contains a base oil and at least one of an ashless fatty-ester friction modifier and an ashless aliphatic-amine friction modifier.

Abstract: A sliding structure for an automotive engine includes a sliding member with a sliding portion and a lubricant applied to the sliding portion so that the sliding portion can make sliding contact with a counterpart member via the lubricant. The sliding member is either of a piston ring, a piston pin, a cam lobe, a cam journal, a plain bearing, a rotary vane and a timing chain. The sliding portion has a base made of a steel or aluminum material and a hard carbon film formed on the base to coat the sliding portion. The hard carbon film has a thickness of 0.3 to 2.0 &mgr;m, a Knoop hardness of 1500 to 4500 kg/mm2, a surface roughness Ry (&mgr;m) satisfying the following equation: Ry<{(0.75−Hk/8000)×h+0.07/0.8}, where h is the thickness (&mgr;m) of the film; and Hk is the Knoop hardness (kg/mm2) of the film.

Abstract: Access history information to respective pages of hypertext is fetched, one or a plurality of pages is/are as a target page or pages, and the fetched access history information is divided into a plurality of sessions each indicating a series of accesses. A page sequence in the order of transition of pages included in each of the divided sessions is generated. Each of the sessions, which accesses the target page, is determined as a successful session, and a session, which does not access the target page, is determined as an unsuccessful session. The number of sessions and success ratio are calculated for each page, and the respective pages are displayed as a graph to have the number of sessions and success ratio as parameters.

Abstract: A rare earth magnet comprises rare earth magnet particles and a rare earth oxide being present between the rare earth magnet particles.

Abstract: A traction drive rotary assembly including a plurality of rolling elements having traction contact surfaces associating with each other to transmit power between the rolling elements. At least one of the traction contact surfaces has a surface microstructure including grooves and protrusions alternately arranged. The surface microstructure is represented by an unfiltered primary profile curve including recesses and projections corresponding to the grooves and the protrusions. Each projection includes a portion located higher than a center line of the unfiltered primary profile curve and having a shape selected from a generally trapezoidal shape with rounded corners, a generally crowning shape, a generally elliptic arc shape, a generally sinusoidal shape and a generally triangular shape with a rounded apex. A ratio &lgr;/AMP of a wavelength &lgr; of the unfiltered primary profile curve to a half depth AMP of the recess is in a range of 50-400.

Abstract: A rotary assembly for traction drives, including a plurality of rolling elements having a rotation axis and traction contact surfaces around the rotation axis and associating with each other to transmit a motive power between the rolling elements via a traction oil film formed between the traction contact surfaces, in which at least one of the traction contact surfaces has a microstructure with irregularities which sizes are larger than a thickness of the traction oil film. The process for the traction contact surface is also disclosed.

Abstract: An electrical-steel-sheet formed body is provided with an opening portion into which a permanent magnet is inserted, and an outer-peripheral hardened portion formed on the electrical-steel-sheet formed body at an outer periphery side thereof for the opening portion and having a higher hardness than a remaining area of the electrical-steel-sheet formed body. The electrical-steel-sheet formed body can be used as the rotor of the built-in permanent magnet type rotary electric machine, and the built-in permanent magnet type rotary electric machine can be obtained.

Abstract: A rotary assembly for traction drives, including a plurality of rolling elements having a rotation axis and traction contact surfaces around the rotation axis and associating with each other to transmit a motive power between the rolling elements via a traction oil film formed between the traction contact surfaces, in which at least one of the traction contact surfaces has a microstructure with irregularities which sizes are larger than a thickness of the traction oil film. The process for the traction contact surface is also disclosed.