Patent ID: 7329198

Claim:
A chain transmission comprising a silent chain in the form of a loop having an inside and an outside, and at least one sprocket inside the loop and having sprocket teeth in mesh with the chain, the chain comprising; link plates, each having a pair of pin insertion holes and a pair of sprocket-engaging teeth, the link plates being disposed in alternating link rows and guide rows, each extending widthwise of the chain, and the link plates of each link row being displaced in the longitudinal direction of the chain relative to, and interleaved with, the link plates of an adjacent guide row, the interleaved link plates being arranged to form an endless loop; guide plates, each having a pair of pin holes, disposed on both sides of the chain in each guide row, each said guide plate having an outer portion positioned toward the outside of the loop, an inner portion positioned toward the inside of the loop, and two end portions each extending in a direction from the inside of the loop toward the outside of the loop; and connecting pins secured to pin holes of the guide plates, and extending through pin holes of the link plates; in which the guide plates have protrusions which contact link plates of the chain adjacent the guide plates; in which each of the guide plates is formed of steel having sufficient springback that its protrusions bias its adjacent link plates toward the opposite side of the chain, whereby biasing forces exerted by the link plates maintain contact pressure between the interleaved link; in which said protrusions of the guide plates are constituted by bent portions formed at the inner portion of each guide plate toward the inside of the loop formed by the chain; and in which each said protrusion of the guide plate in each guide row is located at a position on the guide plate such that, when the outer flanks of the teeth of the link plates in an adjacent link row engage with and disengage from a sprocket tooth at a line of contact, the protrusion is substantially aligned with the line of contact.