Transmission chain

A transmission chain for cooperation with sprockets and comprising alternately outer links and inner links, each outer link comprising two outer plates and spacer members interconnecting the outer plates and each inner link comprising two generally parallel longitudinally extending laterally confronting and laterally spaced apart inner plates and tubular members rigid with the inner plates, the inner plates being trapped between the outer plates and the spacer members extending through the tubular members, each inner plate having two end portions, a center portion which interconnects said end portions and a peripheral edge which is curvilinear in the region of said end portions, said end portions respectively defining planar inner faces which are contained in a common plane, the center portion of each inner plate having at least one part which is deformed throughout its thickness and defines an inner face which extends from said peripheral edge in said center portion and is offset from said common plane laterally outwardly of the corresponding inner link, and the inner link having an outer face which is correspondingly offset laterally outwardly away from the tubular members in said at least one part of said center portion, whereby the lateral spacing between the inner faces defined by said deformed part of said inner portions is larger than the lateral spacing between the inner faces of said end portions which facilitates the engagement of teeth of the sprockets in the inner links, in particular when the chain is shifted by a derailleur, the inner plates having an asymmetrical outer profile as viewed in a direction perpendicular to said common plane and the inner plates of each inner link being disposed in reverse relation to each other.

A transmission chain for cooperation with sprockets and comprising alternatively outer links and inner links, each outer link comprising two outer plates and spacer members interconnecting the outer plates and each inner link comprising two generally parallel longitudinally extending laterally confronting and laterally spaced apart inner plates and tubular members rigid with the inner plates, the inner plates being trapped between the outer plates and the spacer members extending through the tubular members, each innerplate having two end portions, a center portion which interconnects said end portions and a peripheral edge which is curvilinear in the region of said end portions, said end portions respectively defining planar inner faces which are contained in a common plane, the center portion of each inner plate having at least one part which is deformed throughout its thickness and defines an inner face which extends from said peripheral edge in said center portion and is offset from said common plane laterally outwardly of the corresponding inner link, and the inner link having an outer face which is correspondingly offset laterally outwardly away from the tubular members in said at least one part of said center portion, whereby the lateral spacing between the inner faces defined by said deformed part of said inner portions is larger than the lateral spacing between the inner faces of said end portions which facilitates the engagement of teeth of the sprockets in the inner links, in particular when the chain is shifted by a derailleur, the outer plates having an asymmetrical outer profile as viewed in a direction perpendicular to said common plane and the outer plates of each outer link being disposed in reverse relation to each other.