Patent ID: 8157683

Claim:
A chain for a chain transmission with chain links coupled by parallel chain pins, all chain links having link plates, the chain pins forming pivot axes for the link plates at a pitch distance whereby a chain link axis perpendicularly intersects the two pivot axes, said link plates having a longitudinal side and near at least one end side of the longitudinal side of the link plates identical cam surfaces for supporting the link on cylindrical support surfaces on both sides of a sprocket wheel with a pitch angle, characterized in that a parallel part of each cam surface is parallel to the chain link axis, the parallel part starts where a line intersects the cam surface and this line begins at a pivot axis and is perpendicular to the chain link axis and the parallel part ends towards the end of the longitudinal side in an end part and the end part has a convex curved surface with an arc having a radius of curvature that is equal to or larger than half the distance from the chain link axis to the cam surface and the arc has an arc angle of at least half of the pitch angle or at least seven degrees.