摘要 |
<p>Satisfactory durability is realized even when a CVT fluid of low viscosity is used and further the flow rate thereof is limited, and the efficiency of belt type non-stage transmission is enhanced while ensuring the durability. As the material constituting a bearing ring including outer ring (4), use is made of an iron alloy containing 0.15 to 0.5 wt.% of C, 0.1 to 1.5 wt.% of Si, 0.1 to 1.5 wt.% of Mn and 0.5 to 3.0 wt.% of Cr. Not only is this material subjected to carbonitriding, quench hardening, tempering and polish finishing but also a surface layer containing 0.8 to 1.2 wt.% of C and 0.05 to 0.50 wt.% of N is provided at a surface portion of outer ring raceway (6) disposed on an inside wall surface of the outer ring (4). <IMAGE></p> |