Abstract: A self-aligning, anti-cross threading fastener having first and/or second members with lead threads having a curved surface feature from the minor diameter to the major diameter which allows the surface of the lead threads to cam over the mating threads of the other member and thereby aligning collinearly the longitudinal axis of the two members. The initial presentation angle of the two threaded members may be restricted and therefore enhanced by providing a protruding diameter feature.

Abstract: A lead-in point on an end of an externally threaded fastener has a shape in any axial section defined by a curve tangent to the inside of a cylinder formed about the thread axis. The cylinder is of a diameter smaller than the smallest permissible minor (inner) diameter of a mating internal thread, but preferably larger than the minor diameter of the external thread. The length of the lead-in point is preferably from one to three thread pitches. The curved surface of the lead-in point is such that at any practical angle of insertion (where thread engagement is possible), the dimensional characteristics of the lead-in point present only a curved surface (not an edge) for possible contact with the internal threads. This length also insures that the end of the fastener is small enough to feed into internal threads at all angles where such thread contact is effective in producing a threaded joint.

Abstract: A self-aligning, anti-cross threading fastener having first and/or second members with lead threads having a curved surface feature from the minor diameter to the major diameter which allows the surface of the lead threads to cam over the mating threads of the other member and thereby aligning collinearly the longitudinal axis of the two members. The initial presentation angle of the two threaded members may be restricted and therefore enhanced by providing a protruding diameter feature.

Abstract: A self-aligning, anti-cross threading fastener having first and/or second members with lead threads having a curved surface feature from the minor diameter to the major diameter which allows the surface of the lead threads to cam over the mating threads of the other member and thereby aligning collinearly the longitudinal axis of the two members. The initial presentation angle of the two threaded members may be restricted and therefore enhanced by providing a protruding diameter feature.

Abstract: A self-aligning, anti-cross threading fastener having first and/or second members with lead threads having a curved surface feature from the minor diameter to the major diameter which allows the surface of the lead threads to cam over the mating threads of the other member and thereby aligning collinearly the longitudinal axis of the two members. The initial presentation angle of the two threaded members may be restricted and therefore enhanced by providing a protruding diameter feature.

Abstract: A self-aligning, anti-cross threading fastener having a first member with lead threads having a curved surface feature from the minor diameter to the major diameter which allows the surface of the lead threads to cam over the mating threads of a second member and thereby aligning collinearly the longitudinal axis of the two members. The initial presentation angle of the two threaded members may be restricted and therefore enhanced by providing a protruding diameter feature.