Non-loosening luer nut

Claim 1

A Luer nut assembly comprising a female hollow tube having an axis, a radial exterior projection at an end of said female tube, said projection having a given periphery in a plane perpendicular to the axis of the tube, means defining a conical recess in one end of said female tube, a male hollow tube having an external surface at one end thereof that is conical in shape so as to fit into said conical recess when the ends of said female and male tubes are axially drawn together, a shoulder formed on the exterior of said male tube at a point adjacent the lower end of said exterior conical surface, a Luer nut having a body, means defining a cavity in said body having an interior surface extending about an axis, threads formed on said interior surface, said interior surface having a cross-section in a plane perpendicular to said axis that is in the general form of a polygon, and which is enlarged as it approaches one end of said cavity, said nut having an inwardly extending collar at the other end of said cavity that is coaxial with said surface and through which said male tube passes, said collar being axially more remote from said one end of said cavity than said shoulder, and the dimensions and shape of the periphery of said projection being such that it contacts said interior surface of said cavity at at least one point.