ROLLER CHAIN SPROCKET HAVING AN IMPROVED SYMMETRIC TOOTH FORM

摘要

A reduced noise and vibration chain drive system includes a sprocket with a plurality of symmetrical teeth and tooth spaces. A chain is engaged with the sprocket and includes rollers received in the tooth spaces. The root surface of each tooth space includes a modified root surface portion defined with root relief so that a roller fully seated in said tooth space contacts the root surface at first and second circumferentially spaced apart roller-seating locations but is spaced from the root surface between the first and second roller-seating locations. The sprocket is optionally defined with a reduced chordal pitch as compared to the as-built link pitch of the chain. The roller seating diameter of an inscribed circle tangent to a fully seated roller is greater than a root diameter of the sprocket.