Abstract: A thread guide wear testing machine wears a test piece by causing a thread to slide while the thread contacts the test piece. The thread guide wear testing machine includes a winding reel winding the thread thereon fed from thread feeder. A winding drum guides the thread fed from the thread feeder to the winding reel. The winding drum has an outer peripheral surface contacting an outer peripheral surface of the winding reel. Specimen holder is on a path of the thread fed from the thread feeder and moves while being wound on the winding reel. The specimen holder holds the test piece in contact with the thread under a predetermined load. Tension adjuster adjusts tension on the thread when the test piece is in contact. Contact retainer retains a state of contact between the winding reel and the winding drum by pressing the winding reel toward the winding drum.

Abstract: A steel sheet has a composition containing, in mass %, from 0.60 to 1.25% of C, 0.50% or less of Si, from 0.30 to 1.20% of Mn, 0.030% or less of P, 0.030% or less of S, from 0.30 to 1.50% of Cr, from 0.10 to 0.50% of Nb, from 0 to 0.50% of Ti, from 0 to 0.50% of Mo, from 0 to 0.50% of V, from 0 to 2.00% of Ni, the balance being Fe with unavoidable impurities. A ferrite phase as a metal matrix has dispersed therein cementite particles and Ni—Ti based carbide particles. A number density (cross section parallel to rolling and thickness directions) of the carbide particles having a circle equivalent diameter of 0.5 ?m or more is from 3,000 to 9,000 per mm2 and a number density of voids having a circle equivalent diameter of 1.0 ?m or more is 1,250 per mm2 or less.

Abstract: A steel sheet for textile machinery parts manufactured at a low cost and is excellent in wear resistance and toughness. The steel sheet for textile machinery parts contains, in mass %, 0.60% or more and 1.25% or less C, 0.50% or less Si, 0.30% or more and 1.20% or less Mn, 0.03% or less P, 0.03% or less S, 0.30% or more and 1.50% or less Cr, and 0.10% or more and 0.50% or less Nb, with the balance being Fe and unavoidable impurities. Furthermore, Nb-containing carbides having a particle size of 0.5 ?m or more are present in the matrix at a density of 3000/mm2 or more and 9000/mm2 or less. Nb-containing carbides' effect of improving wear resistance can be ensured, and deterioration in toughness due to excessive formation of Nb-containing carbides can be prevented. Hence, the resulting wear resistance and toughness are good.

Abstract: A method for producing a high fatigue life quenched/tempered steel pipe comprises a quenching treatment of keeping an unquenched starting steel pipe having a composition that comprises, % by mass, C: 0.1 to 0.4%, Si: 0.5 to 1.5%, Mn: 0.3 to 2%, P: at most 0.02%, S: at most 0.01%, Cr: 0.1 to 2%, Ti: 0.01 to 0.1%, Nb: 0.01 to 0.1%, Al: at most 0.1%, B: 0.0005 to 0.01%, and N: at most 0.01%, with a balance of Fe and inevitable impurities, at 900 to 1100° C. for 10 to 60 seconds and then rapidly cooling it. The cooled pipe is subjected to a tempering treatment of keeping the pipe at 280 to 380° C. for 10 to 60 minutes.

Abstract: A seat lifter smoothly lifts and lowers right and left seat frames relative to respective base members so that a seat can be lifted and lowered smoothly. The seat lifter has first to fourth links (4a to 4d), and a coupling (6) that couples the first link (4a) and the second link (4b), and has a first sun gear (62) and a second sun gear (162). The first link (4a) has a first link body (41) that is coupled interlockably to a first planetary gear group (40) with a plurality of first planetary gears (44), and a planetary-gear operating section (5). The second link (4b) has a second link body (141) that is coupled interlockably to a second planetary gear group (140) with a plurality of second planetary gears (144).

Abstract: A method for producing a high fatigue life quenched/tempered steel pipe comprises a quenching treatment of keeping an unquenched starting steel pipe having a composition that comprises, % by mass, C: 0.1 to 0.4%, Si: 0.5 to 1.5%, Mn: 0.3 to 2%, P: at most 0.02%, S: at most 0.01%, Cr: 0.1 to 2%, Ti: 0.01 to 0.1%, Nb: 0.01 to 0.1%, Al: at most 0.1%, B: 0.0005 to 0.01%, and N: at most 0.01%, with a balance of Fe and inevitable impurities, at 900 to 1100° C. for 10 to 60 seconds and then rapidly cooling it. The cooled pipe is subjected to a tempering treatment of keeping the pipe at 280 to 380° C. for 10 to 60 minutes.

Abstract: A steel plate for band-shaped die-cutting blades has a base part to a depth of more than 200 ?m from the steel plate surface and a chemical composition containing 0.40 to 0.80 mass % C and 0.10 to 0.50 mass % Nb. A spherical carbide constituted of cementite is present in the bainite or tempered martensite structure of the blade in an amount of 1.0 vol % or more. A Nb-containing carbide having an equivalent-circle diameter of 0.5 ?m or more is present at an existential density of 10.0 or more grains per 900 ?m2. The base part has a controlled hardness of from 300 to 450 HV. The surface layer part has a decarburized surface layer of ferrite single-phase and a thickness of 5 ?m or more. In a 15-?m-thick surface layer region, the existential density of the Nb-containing carbide is from 0 to 5.0 grains per 900 ?m2.

Abstract: Provided is a steel pipe designed to have a further increased high strength and a further improved fatigue life with suppressing the material cost and the production cost, especially such a steel pipe suitable for machine structure members that are required to be lightweight. The steel pipe is a high fatigue life steel pipe produced according to a process of using a steel plate having a composition that comprises, % by mass, C: 0.1 to 0.4%, Si: 0.5 to 1.5%, Mn: 0.3 to 2%, P: at most 0.02%, S: at most 0.01%, Cr: 0.1 to 2%, Ti: 0.01 to 0.1%, Nb: 0.01 to 0.1%, Al: at most 0.1%, B: 0.0005 to 0.01%, N: at most 0.01%, and optionally at least one of Ni: at most 0.5%, Ca: at most 0.02%, Mo: at most 0.5%, and V: at most 0.5%, with a balance of Fe and inevitable impurities, and having, on at least one side thereof, a smoothed surface of which the surface roughness Ra in the direction (C direction) perpendicular to the direction to be the longitudinal direction of the steel pipe is at most 0.

Abstract: A seat lifter smoothly lifts and lowers right and left seat frames relative to respective base members so that a seat can be lifted and lowered smoothly. The seat lifter has first to fourth links (4a to 4d), and a coupling (6) that couples the first link (4a) and the second link (4b), and has a first sun gear (62) and a second sun gear (162). The first link (4a) has a first link body (41) that is coupled interlockably to a first planetary gear group (40) with a plurality of first planetary gears (44), and a planetary-gear operating section (5). The second link (4b) has a second link body (141) that is coupled interlockably to a second planetary gear group (140) with a plurality of second planetary gears (144).

Abstract: Provided is a steel pipe suitable for machine structure members that are required to be lightweight, of which the strength is increased and the fatigue life is prolonged with preventing the increase in the material cost and the production cost. The steel pipe is a high fatigue life quenched/tempered steel pipe having a composition comprising, % by mass, C: 0.1 to 0.4%, Si: 0.5 to 1.5%, Mn: 0.3 to 2%, P: at most 0.02%, S: at most 0.01%, Cr: 0.1 to 2%, Ti: 0.01 to 0.1%, Nb: 0.01 to 0.1%, Al: at most 0.1%, B: 0.0005 to 0.01%, N: at most 0.01%, and optionally at least one of Ni: at most 0.5%, Ca: at most 0.02%, Mo: at most 0.5% and V: at most 0.5%, with a balance of Fe and inevitable impurities, in which the mean grain size of the precipitated carbides is at most 0.5 ?m and of which the hardness in the center part of the wall thickness in the cross section perpendicular to the longitudinal direction of the steel pipe is at least 400 HV.