| 摘要 |
PURPOSE:To restrain metal contact through the improvement of the oil film formation rate of a sprag cam surface, and prevent the wear and peeling damage, by forming independent, minute, recess-shaped hollows innumerably and randomly on the outer surface of a sprag of an engagement type. CONSTITUTION:When the surface roughness of a minute rough surface 11a formed at the cam surface of a sprag 11 in a random direction, is indicated by means of a parameter RMS by seeking each of the shaft direction and the perimeter direction of the cam surface, the ratio of a width direction surface roughness to a perimeter direction surface roughness RMS(L)/RMS(C) is made to be less than 1.0 at the mean value, and at the same time, the parameter SK value of the surface roughness is to come off less than -1.6 at the mean value both in the shaft direction and circumferential direction. The surface processing whose purpose is to obtain such a cam surface rough surface condition as this, is done by means of a special barrel polishing, and a finished surface is obtained. Thus, the durability of a one way clutch using an engagement type sprag can be made to improve drastically. |
