Ntn Corporation

Kousuke Obayashi

Shinji Oishi

Tetsuya Hayashi

Yasuyuki Watanabe

Shingo Kono

Hideki Akamatsu

Kazuyuki Yamamoto

Takumi Fujita

Kazuyoshi Harimoto

Tomoaki Kawamura

Masatoshi Niina

Ayumu Yamamoto

Seiji Takahashi

A roller follower includes a roller ring, a shaft and a plurality of rollers. At least one of the roller ring, the shaft and the rollers is a steel member made of steel containing 0.7 to 2.4% carbon and 10.0 to 20.0% chromium, with remainder iron and impurities. In addition, carbide containing at least any one of iron and chromium as well as carbon and having an area of 12.6 &#x3bc;mor greater is generated at an area ratio of 5.0% or higher, at a rolling contact surface of the steel member (a roller ring rolling contact surface, a shaft rolling contact surface and a roller rolling contact surface.

Roller follower, valve train, induction hardening apparatus, method of heat treatment of shaft member, method of manufacturing shaft, and shaft

A thrust bearing component is formed of cold-reduced steel sheets and strip having surface roughness of Rmax&#x2266;2 &#x3bc;m and provided by cold rolling a high-carbon steel containing 0.9 wt % to 1.2 wt % of carbon, 1.2 wt % to 1.7 wt % of chrome, 0.1 wt % to 0.5 wt % of manganese, and 0.15 wt % to 0.35 wt % of silicon.

Thrust bearing component

A thrust roller bearing comprises a plurality of rollers and a disk-shaped retainer having a plurality of pockets for holding the plurality of rollers and having an outer flange part bent in a rotation axis direction. The inner surface of the outer flange part forms the outer wall surface of the pocket and the outer wall surface of the pocket is processed by the ironing.

Thrust roller bearing

A roller bearing utilizing a roller retainer, which has an excellent assemblability in the sense that the assembly line can be automated and which eliminates various problems inherent in the full complement roller bearing The roller bearing includes an outer race having a raceway, a plurality of rollers held in rolling contact with the raceway, and a ring-shaped roller retainer having a plurality of pockets, each rollingly receiving the respective roller, spacedly defined therein in a direction circumferentially thereof to form a ladder-like structure. The roller retainer has a plurality of slits that are spacedly defined in a direction circumferential thereof so as to extend from one axial end or the other axial end of the roller retainer to a position adjacent the other axial end or one axial end.

Roller bearing and method of assembling the same

A thrust roller bearing comprises a plurality of cylindrical rollers each having a rolling surface on its side surface and a cage formed of a disk-shaped member having a hole formed in the center and comprising a plurality of pockets penetrating in a thickness direction for housing the rollers. The pocket has a plurality of stopper parts at a wall surface opposed to the rolling surface of said roller, and a plurality of guide parts between said adjacent stopper parts. When it is assumed that the distance between the outer wall surface of said pocket in the diameter direction and the guide part located on the outer side in the diameter direction of the two guide parts is Land the distance between the inner wall surface of said pocket in the diameter direction and the guide part located inner side in the diameter direction of the two guide parts is L, it is satisfied that L&#x3e;L.

Manufactured by quench hardening, a bearing washer for a thrust bearing inexpensive and excellent in durability is used without being subjected to grinding after quenching. In a bearing washer group including a plurality of bearing washers for the thrust bearing, when camber/waviness of each bearing washer constituting the bearing washer group that is randomly extracted is measured, a value obtained by adding a value three times as large as standard deviation of camber/waviness to an average value thereof is at most 40 &#x3bc;m.

Bearing washer for thrust bearing and thrust bearing

A thrust needle roller bearing has a washer formed of a thin steel plate and needle rollers, at least said washer has a nitrogen enriched layer at a surface layer portion, amount of retained austenite in said surface layer portion is at least 5 volume % and at most 25 volume %, and austenite grain number of said surface layer portion is 11 or higher. Thus, a long life thrust needle roller bearing resistant to an early failure caused by surface damage such as surface-originated flaking and also resistant to common, load dependent rolling contact fatigue can be provided.

Thrust needle roller bearing, support structure receiving thrust load of compressor for car air-conditioner, support structure receiving thrust load of automatic transmission, support structure for continuously variable transmission, and support structure receivin

A support structure carries a thrust load of a transmission which includes a torque converter having an impeller and a turbine opposite to each other with a stator therebetween. A thrust needle roller bearing having needle rollers arranged in two rows is provided at, at least one of places respectively between the stator and the impeller and between the stator and the turbine. The support structure carrying a thrust load of the transmission, a method of manufacturing the support structure and the thrust needle roller bearing are thus obtained, with an improvement in inflow and outflow of a lubricating oil, a reduction of the differential slip of the needle rollers, and an improvement in strength durability.

Support structure carrying thrust load of transmission, method of manufacturing thereof and thrust needle roller bearing

A support structure carrying a thrust load of a compressor has a swash plate which contributes to a compressing operation by rotating according to rotation of a rotating shaft which is rotatably supported by a housing. The swash plate is rotatably supported with respect to the housing, and the support structure includes a thrust needle roller bearing having double-row needle rollers. The support structure carrying a thrust load of a compressor and the thrust needle roller bearing are thus obtained, with an improvement in inflow and outflow of a lubricating oil, a reduction of the differential slip of the needle rollers, and an improvement in strength durability.

Support structure carrying thrust load of compressor and thrust needle roller bearing

To provide a roller bearing assembly that can provide a high load bearing capacity and in which the strength of roller retainers can be increased, the roller bearing assembly includes inner and outer roller retainers () each having a plurality of circumferentially arranged pockets (), and a circular row of rollers () received in part within the pockets in the inner roller () and in part within the pockets in the outer roller (). The inner roller retainer () has pillars () each left between the neighboring pockets to retain the circular row of the rollers from radially inwardly and having an outer diameter smaller than the diameter of the pitch circle PCD of the circular row of the rollers. The outer roller retainer () has pillars () each left between the neighboring pockets to retain the circular row of the rollers from radially outwardly and having an inner diameter greater than the pitch circle diameter PCD. One of the outer and inner roller retainers is made of a metallic material while the other thereof is made of a resinous material.

Roller bearing assembly

A thrust needle roller bearing and a method for manufacturing the bearing with improved lubricant circulating ability, reduced drilling abrasion of the cage, and improved durability of the bearing has a plurality of needle rollers and two annular cages. Each of the cages is formed with a plurality of pockets. Each pocket has a radial length longer than the height of the roller. The two annular cages hold the needle rollers by sandwiching them between the cages within roller holding portions formed in the pockets. The radial length of each of the roller holding portions of the cages is formed shorter than the height of the roller. The two cages are assembled by folding them as a unit so that both the portions of the unit on either radially outer and inner side of the roller holding portions have their axial thickness smaller than that of the roller holding portions. The two cages are secured to one another at both their radially outermost and innermost end portions.

Thrust needle roller bearing and method for manufacture thereof

To provide a roller bearing assembly, which can be assembled with a minimized number of assembling steps and without any drop-off preventing sleeve being employed and which can provide a large load bearing capacity, the roller bearing assembly includes an inner racehaving a raceway surfacedefined therein, a plurality of rollers, and a ring-shaped roller retainerhaving a plurality of pocketsdefined therein in a direction circumferentially thereof for accommodating therein the respective rollersin a circular row. The roller retaineralso has pillarseach defined between the neighboring pockets. The roller retaineris positioned on the inner racewith each of the pillarsthereof intervening between the neighboring rollersto thereby retain the rollersin position within the respective pocketsfrom a direction radially outwardly of the row of the rollers. The diameter of the circle depicted by and in touch with the pillarsis chosen to be greater than the diameter of the pitch circle PCD depicted in the circular row of the rollers

Roller bearing

A thrust needle roller bearing includes a plurality of needle rollers, and an annular retainer having a plurality of pockets for retaining the needle rollers. The plurality of pockets accommodate the needle rollers arranged in multiple rows shifted from each other in a radial direction of the retainer, and the retainer is made of synthetic resin. The thrust needle roller bearing is light, can reduce friction between the retainer and the needle rollers, and has high durability.

Thrust needle roller bearing

An object is to provide a cage and a thrust roller bearing with improved oil passage performance of a lubricating oil in the inside of a bearing while holding a needle roller in a stable manner so as to ensure excellent durability. The thrust roller bearing includes a needle roller and a cage holding the needle roller in pockets for accommodating the same. A length La of a roller holding portion provided in the pocket is set to be within a range of 30% to 80% of a length in a radial direction of the pocket.

Growing community of inventors

Iwata, Japan

Kousuke Obayashi