Abstract
This paper introduces a creative synthesis and analysis of stroke-increasing and force-balancing mechanisms for rod oil pumping units by using the systematic linkage technique. The corresponding relations between the kinematic components in mechanisms and the link element in associated linkage are determined. Four acceptable associated linkages are used to create eight new types of mechanisms for rod oil pumping units. Formulas are derived for calculating stroke, counterweight mass, and driving force. For each synthesized mechanism, an analysis of properties, working loads, and strokes is conducted. Finally, a better mechanism for the rod oil pumping units is presented.