Koyo Seiko Company, Ltd.

Jtekt Corporation

Daisaku Tomita

Kazutoshi Toda

Shinichirou Kashiwagi

Tomohiro Ishii

Tadashi Mitarai

Masaru Deguchi

Naoki Morimura

Eiji Murata

A bearing device is provided with a bearing ring and a shaft body that is made of carbon steel including pearlite having a cementite layer structure, and has an end portion caulked onto the bearing ring, and in this device, at least in the end portion of the shaft body, the layer gap of the cementite in the pearlite is made greater.

Bearing device and method of manufacturing the bearing device

A vehicle-use bearing apparatus including a hub wheel formed of steel material to which a wheel is mounted and a rolling bearing mounted to an outer periphery of the hub wheel. An end portion of the hub wheel is expanded radially outward toward an inner ring provided to the rolling bearing to be formed into a caulked portion and a percentage of sulfur content is adjusted to be 0.020% by weight or less in steel material of which the 10 caulked portion is formed.

Vehicle-use bearing apparatus

In a bearing device in which a free end of a shaft body to which a rolling bearing is mounted is bent outward in its radial direction into a shape to be pushed against an end face of an inner ring of the rolling bearing so as to prevent the rolling bearing from falling out, a raceway surface of the inner ring of the rolling bearing is subjected to hardening treatment, and another portion of the inner ring is made of raw material which is not hardened. With this arrangement, the caulked portion formed by the caulking plastically deforms the relatively soft inner peripheral corner of the inner ring and as a result, the caulked portion and the inner peripheral corner are adhered to each other strongly.

Bearing device

A rolling bearing unit includes a shaft body, an inner ring mounted on the shaft body, an outer ring concentric with the inner ring, and a plurality of balls between the inner ring and the outer ring. A caulking portion to be caulked onto the outer end face of the inner ring is formed on the shaft body. A pre-load is applied to the balls to fix the inner ring to the shaft body. The retained austenite amount of an edge of the inner ring in the vicinity of the caulking portion is between 3% or more and 20% or less.

Rolling bearing unit

The present invention relates to an axial force controlling method for controlling an axial force applied to a rolling bearing in a bearing apparatus having a shaft body, the rolling bearing being mounted to the shaft body such that the rolling bearing fits an outside of the shaft body, and the bearing apparatus.

Axial force controlling method and bearing apparatus

A double row tapered roller bearing with vertex of contact angles outside of the bearing is externally fitted to an outer periphery of a hub wheel to which a wheel is attached. A shaft end of the hub wheel is deformed outwardly in a radial direction so as to be caulked to an outer end surface of an inner ring of the bearing. A raceway track of at least one of the inner ring and the outer ring in the bearing is designed so as to satisfy a condition that a predetermined form is secured in a state that the raceway track is elastically deformed by the caulking. As a result, satisfactory rolling performance of the tapered roller after the caulking is secured, and a predetermined life of the bearing apparatus after the caulking can be obtained.

A bearing device comprising a shaft body having an axially cylindrical portion in a free end side thereof and a rolling bearing fitted around an outer peripheral surface of the shaft body, wherein the cylindrical portion is bent and deformed radially outward by a rolling caulking to be caulked thereby on an outer end face of an inner ring of the rolling bearing. An inner peripheral surface of the cylindrical portion is formed by a turning work, and a residual stress left in a surface layer of the inner peripheral surface of the cylindrical portion by the turning work is set to a value capable of restraining a crack generation ratio in the inner peripheral surface to less than a predetermined rate, desirably to not more than 5 kgf/mm .

A bearing device comprising a shaft body having an axially cylindrical portion in a free end side thereof and a rolling bearing fitted around an outer peripheral surface of the shaft body, wherein the cylindrical portion is bent and deformed radially outward by a rolling caulking to be caulked thereby on an outer end face of an inner ring of the rolling bearing, and a surface roughness of the inner peripheral surface of the cylindrical portion is set to 12.5 &mgr;m or less by a ten-point mean roughness (Rz).

A vehicle-use bearing apparatus including a hub wheel formed of steel material to which a wheel is mounted and a rolling bearing mounted to an outer periphery of the hub wheel. An end portion of the hub wheel is expanded radially outward toward an inner ring provided to the rolling bearing to be formed into a caulked portion and a percentage of sulfur content is adjusted to be 0.020% by weight or less in steel material of which the caulked portion is formed.

In a bearing device in which a free end of a shaft body to which a rolling bearing is mounted is bent outward in its radial direction into a shape to be pushed against an end face of an inner ring of the rolling bearing so as to prevent the rolling bearing from falling out, a raceway surface of the inner ring of the rolling bearing is subjected to hardening treatment, and other portion of the inner ring is made of raw material which is not hardened. With this arrangement, the caulked portion formed by the caulking plastically deforms the relatively soft inner peripheral corner of the inner ring and as a result, the caulked portion and the inner peripheral corner are adhered to each other strongly.

Growing community of inventors

Kashiwara, Japan

Daisaku Tomita