Patent ID: 8052561

Claim:
A method for optimizing plate geometry of a plate of a plate link chain for use in a variable speed drive unit of a belt-driven conical-pulley transmission, said method comprising the steps of: defining for a chain a predetermined applied longitudinal force to be transmitted by the chain and a predetermined applied longitudinal force lever arm; providing an initial plate geometry for a plate that includes an opening for receiving pairs of rocker members that bear against sides of the opening, wherein the opening is bounded by spaced longitudinal legs that extend in a chain movement direction and spaced vertical legs that extend in a direction perpendicular to the chain movement direction, wherein the initial plate geometry includes an initial longitudinal leg length and longitudinal leg width, an initial vertical leg length and vertical leg width, and an initial plate thickness; determining a bending moment (MB) acting on the longitudinal legs of the plate when the plate is subjected to a predetermined applied longitudinal force that is applied at a predetermined lever arm distance relative to the longitudinal leg from the following bending moment relationship based upon the following plate geometry variables: MB = ⁢ F * He k + 1 · [ 1 - He L ⁢ ⁢ 2 ] ⁢ ⁢ with ⁢ ⁢ k = I ⁢ 2 * L ⁢ 1 I ⁢ 1 * L ⁢ 2 , wherein F = ⁢ applied ⁢ ⁢ longitudinal ⁢ ⁢ force ⁢ He = ⁢ lever ⁢ ⁢ arm ⁢ ⁢ of ⁢ ⁢ the ⁢ ⁢ applied ⁢ ⁢ force ⁢ ⁢ F I ⁢ ⁢ 1 ⁢ = ⁢ planar ⁢ ⁢ moment ⁢ ⁢ of ⁢ ⁢ inertia ⁢ ⁢ of ⁢ ⁢ the ⁢ ⁢ longitudinal ⁢ ⁢ leg ⁢ ⁢ ( = ⁢ ⁢ leg ⁢ ⁢ height 3 * ⁢ leg ⁢ ⁢ thickness / 12 ) I ⁢ ⁢ 2 = ⁢ planar ⁢ ⁢ moment ⁢ ⁢ of ⁢ ⁢ inertia ⁢ ⁢ of ⁢ ⁢ the ⁢ ⁢ vertical ⁢ ⁢ leg ⁢ ⁢ ( = ⁢ ⁢ leg ⁢ ⁢ width 3 * ⁢ leg ⁢ ⁢ thickness / 12 ) L ⁢ ⁢ 1 = ⁢ overall ⁢ ⁢ length ⁢ ⁢ of ⁢ ⁢ the ⁢ ⁢ longitudinal ⁢ ⁢ leg L ⁢ ⁢ 2 = ⁢ overall ⁢ ⁢ length ⁢ ⁢ of ⁢ ⁢ the ⁢ ⁢ vertical ⁢ ⁢ leg . modifying respective ones of the plate geometry variables; and calculating longitudinal leg bending moments for different plate longitudinal leg lengths and different longitudinal leg planar moments of inertia at the predetermined applied longitudinal force and the predetermined applied longitudinal force lever arm until a minimum longitudinal leg bending moment is achieved to thereby provide a plate of minimum longitudinal leg material usage and minimum longitudinal leg weight for the predetermined longitudinal force that is applied to the plate opening at the predetermined lever arm distance relative to the longitudinal leg.