US Patent 10131012 Collision sensing system for rotary welding torch

A collision sensing system includes an outer housing with a ball roller mounted thereto, a piston, a lower housing, and an electro/mechanical switch assembly having a contact ring. The piston includes a helical groove on its exterior and a tongue extending from a lower end thereof. The ball roller is positioned within the helical groove of the piston. The lower housing has a semi-spherical portion and a groove aligned with the piston tongue. A contact pin assembly extends through the piston and includes a contact pin positioned to contact the contact ring. The collision sensing system is configured such that deflection of a welding torch mounted to the lower housing misaligns the tongue and groove, slides the helical groove along the ball roller, thereby lifting the piston and breaking contact between the contact pin and contact ring.