Electrical outlet box with integral screw aligning, engaging and retaining boss

Claim 1

A nonmetallic box for supporting a device via a threaded screw, the screw threads having a crest diameter and a root diameter, the combination comprising: a boss integrally formed with the box and having a planar front face and a straight bore extending inwardly of said boss from said front face and substantially perpendicularly to said front face for receiving the screw, said bore comprising in sequence from said front face aligning and engaging means for angularly aligning the screw substantially coaxially of said bore and engaging the screw to resist inadvertent removal of the screw from said bore, said aligning and engaging means comprising in sequence an inwardly tapering frustoconical section followed by a cylindrical portion, said frustoconical section having its largest diameter at said front face of said boss, said cylindrical portion having a diameter substantially equal to the crest diameter, and retaining means for retaining the screw in said boss substantially coaxially of said bore and for preventing removal of the screw therefrom by application only of an axial force, said retaining means comprising a single cylindrical surface having a diameter less than the crest diameter but greater than the root diameter, said retaining means being self-tapping and threadedly retaining the screw upon rotation of the screw in said retaining means, said frustoconical section, said cylindrical portion and said cylindrical surface being co-axial and integral.