Abstract:

Based on the analysis of existence of cranks in four-bar spatial, spherical and planar mechanisms, is stated the theorem of existence of two cranks in spatial five-bar hinged mechanisms. In accordance with Grashhof’s theorem it is widespread on four-bar spatial mechanisms as well as on five-bar and four-bar spherical and planar hinged mechanisms. The formulated theorem represents the general and universal.

Keywords: Theorem of existence of cranks; spatial and spherical five-bar mechanisms; spherical and planar four-bar mechanisms.