Patent ID: 6629906
Filing Date: 2003-10-07
Classification: F16H,Y10T

Abstract:
A rotary assembly for traction drives, comprising:a plurality of rolling elements having a rotation axis and traction contact surfaces around the rotation axis and associating with each other to transmit a motive power between the rolling elements via a traction oil film formed between the traction contact surfaces; at least one of said traction contact surfaces having a microstructure with irregularities which sizes are larger than a thickness of the traction oil film, wherein the microstructure is represented by an unfiltered primary profile curve including alternately arranged recesses and top-flat lands, wherein the unfiltered primary profile curve is measured using a surface roughness tester, each of said lands of the unfiltered primary profile curve including a portion located higher than a center line with respect to the unfiltered primary profile curve where the center line is drawn at an average height determined by integrating the unfiltered primary profile curve in the direction of length, said portion having either one shape selected from a generally trapezoidal shape, a generally trapezoidal shape with rounded corners, a generally trapezoidal shape with chamfered corners, a generally crowning shape, a generally elliptic arc shape, a generally sinusoidal shape and a generally triangular shape with a rounded apex, wherein a height difference between a top of each land and a bottom of each recess is within a range of 0.5-2.5 &mgr;m.