Patent ID: 7846050

Claim:
A power transmission chain comprising: a plurality of first pins; a plurality of second pins; and a plurality of links each having front and rear passage portions for the passage of the first and second pins therethrough, wherein the first pins and the second pins are arranged in a forward-rearward direction, and interconnect the links arranged in a direction of a width of the chain such that the front passage portion of one link corresponds to the rear passage portion of other link, and the first pin and the mating second pin move relative to each other in rolling contact with each other such that the links can be bent relative to each other in a direction of a length of the chain, wherein the plurality of first pins comprise a length which is substantially equal in an axial direction, wherein two kinds of pins comprising rolling contact surfaces of different shapes are used as the plurality of first pins, wherein a discrimination portion is formed at a part of each of the first pins of two kinds and disposed between a chain outer periphery-side edge portion thereof and the rolling contact surface thereof, and enables the first pin of one of the two kinds to be discriminated from the first pin of the other kind from their appearance, and wherein the discriminatio portion of a first pin of the one kind of the plurality of first pins comprises a straight shape in transverse cross-section, while the discrimination portion of a first pin of the other kind of the pluiality of first pins comprises a concave generally-arc-shape in transverse cross-section.