ON THE UNITY VELOCITY RATIO OF SPHERICAL DRAG-LINKS

Drag-link is a synonym of double-crank mechanism. The value of the vel ocity ratio of a planar drag-link becomes unity twice within one cycle of motion. In a spherical drag-link the velocity ratio i reaches unit y twice or four times, or even three times. The present paper is to in vestigate the number of occurrence of i = 1 of a spherical drag-link i n relation to the four link lengths. All discriminants are listed in a tabular form to facilitate immediate location of the appropriate disc riminant for a certain case.