Umbrella rib linkage system

摘要

A rib linkage system of the topless type. A stretcher rib connects the umbrella's runner with each cover rib, a support rib connects the umbrella's ferrule with each stretcher rib, and a control link connects each support rib with its associated cover rib. The connection of the support rib with the stretcher rib is by means of a split or bifurcated brace structure that enhances the stability of the linkage system when the umbrella is full opened. The control link, support rib, stretcher rib, and cover rib all cooperate to define a generally parallelogram configuration beneath the stretcher rib when the umbrella is in between its full opened and full closed positions, and to define a generally triangular configuration when the umbrella is full opened, again to enhance the stability of the linkage system when the umbrella is opened and also to permit the umbrella to collapse into a short and compact storage or full closed position.