Input Torque Balancing Using an Inverted Cam Mechanism

Abstract

Input torque balancing through addition of an auxiliary, input torque balancing mechanism, is a well-known way for reducing drive speed fluctuations in high-speed cam-follower mechanisms. This paper develops a methodology to design and optimize the so-called inverted cam mechanism (ICM), a simple, cam-based input torque balancing mechanism. It was already introduced in the 1950s, but the design methodologies proposed by Meyer zur Capellen (1964) and Michelin (1979) are, respectively, erroneous or too rough an approximation, and are corrected here. The describing equation that governs the ICM cam design, is shown to be a second-order, nonlinear, ordinary differential equation. It is solved by parameterizing its solution as a finite Fourier series, the coefficients of which are determined through a nonlinear least-squares problem. Based on this methodology, an ICM is designed for input torque balancing a high-speed, industrial cam-follower mechanism. The ICM’s design parameters result from a design optimization, which aims at obtaining a compact and technologically feasible mechanism. The optimization problem is solved using a design chart, which is efficiently created based on a nondimensionalized analysis.