Structural Synthesis of Planar Geared Linkage Mechanisms as Multibody Systems

Geared linkage structure is defined in literature considering the type of linkage, usually four-bar or five-bar, and different versions are obtained by changing the input/output, the fixed link and the gears connections with linkage links. The paper proposes the structural synthesis of the planar geared linkage mechanisms with one pair of gears, as multibody systems with four bodies. The algorithm derived from the structural synthesis of the linkages as multibody systems with four bodies lead to eight distinct general kinematic chains, from which two contain a rigid sub-chain and, from the other six, only four contain the sub-chain formed by three bodies with five kinematic constraints. Replacing these sub-chains by the gearing sub-chain, seven variants of distinct kinematic chains with 1 DOF for geared linkages are identified (four general and three particular). Based on these, 27 distinct geared linkage mechanisms were obtained. This approach allowed to identify already known mechanisms but also new ones.