US Patent 10393167 Self-locking plug assembly

A self-locking plug assembly is provided that includes a plug, a lower clutch disposed around the plug and defining engagement features, an upper clutch disposed around the plug and defining mating engagement features, a resilient member and a cap surrounding the resilient member and disposed around a proximal end portion of the plug. The mating engagement features are configured to apply higher torque to the engagement features in one direction than in an opposite direction. In one form, the engagement features of the lower clutch and upper clutch comprise a plurality of teeth arranged around a central aperture.