ball joint

Werner O. Merlo’s patio umbrella refused to stay locked in a tilted position. Frustrated, he replaced the sagging sunshade’s flimsy ball-and-joint with a self-designed mechanism that swiveled smoothly yet held fast at an angle. His umbrella never flopped over again. "I'm not really the umbrella-manufacturing type, so the first thing that came to mind was, What else can I use this for?" says Merlo, a former chemist at the University of Alberta.