An Innovative Ratchet Fastener That Cannot Screw Loose
On the Shoulders of Giants Have you ever heard of Archytas of Tarentum? Back in 400 BC, he laid the foundation for modern fasteners by inventing the helical thread. But just as what goes up must come down, we also know that when helically threaded fasteners screw loose, things fall apart.
Screwed By Tradition – The helical thread is a genius design. It fastens by tightening in one direction and unfastens by loosening in the other. Yet shear forces and axial movements at the interface between the fastener and the clamped components result in small relative motions called microslip that gradually reduce the fastener’s preloaded frictional force and cause microscopic deformation of the threads.