Nsk Corporation

Keijiro Yamaguchi

Koji Ueda

Takashi Murai

Manabu Ohori

Osamu Fujii

Kouji Ueda

Shinichi Tsunashima

A brass is a base material, and a material containing Mn and Si is cast to make a ring material. Ametallic structure in the cross section of the ring material is under a condition where an intermetallic compound Mn Si is uniformly and finely scattered and precipitated in the base material (brass composed of &agr;- and &bgr;-phase). A machined retainer provided by matching said material has an excellent sizing precision, sound affect resistance.

Retainer

A cage is made of a low carbon steel and is for use in a rolling bearing which includes an outer ring, an inner ring and a plurality of rolling elements disposed rotationally between the outer ring and the inner ring. The cage includes a plurality of pockets for retaining the rolling elements in an equi-distribution in the rotating direction of the rolling elements. The low carbon steel is a steel containing from 0.02 to 0.10% by weight of C and from 0.10 to 0.45% by weight of Mn and is subjected to plastic working. The hardness for the pocket surface at least at a portion in contact with the rolling element is Hv 190 to 270, and the hardness for the core portion in the cage section is Hv 110 to 170.

Cage for roller bearing

In a steel cage for rolling bearing which is nitrided to form a compound layer on the surface thereof, when the thickness of a dense layer in the compound layer is predetermined to a range of from 3 &mgr;m to 20 &mgr;m, the abrasion can be inhibited, improving the abrasion resistance. Further, when a porous layer which acts as a lubricant reservoir is predetermined to a range of from 2 &mgr;m to 25 &mgr;m, the exhaustion of lubricant can be inhibited, improving the seizing resistance.

Growing community of inventors

Kanagawa, Japan

Keijiro Yamaguchi