US Patent 7273236 Quick coupling

A quick coupling comprising a body with a conical opening and an outside thread, a nut with a central through orifice and a cylindrical counterbore extending the through orifice and tapped over its portion that is remote from the through orifice, and a conical surface connecting the through orifice to the counterbore, the coupling comprising a ring housed in the counterbore of the nut, the ring having a front face directed towards the thread that is fitted with a sealing gasket whose rear face facing towards the coupling surface co-operates therewith to define a radial expansion housing for a split spring washer.