Plastic screw anchor

Claim 1

A ONE PIECE PLASTIC ANCHOR MEMBER FOR APPLICATION TO AN APERTURED WORK PEICE IN POSITION TO ACCOMODATE A SCREW MEMBER HAVING A THREADED SHANK OF A PREDETERMINED DIAMETER, SAID PLASTIC ANCHOR MEMBER INCLUDING A HEAD SECTION PROVIDING A SURFACE FOR ENGAGING ONE SIDE OF SAID WORK PIECE AFTER INSERTION WITHIN THE APERTURE THEREOF, AND A SHANK SECTION EXTENDING AXIALLY FROM SAID HEAD SECTION AND HAVING A POLYGONAL TRANSVERSE CROSS-SECTION, SAID SHANK SECTION BEING INSERTABLE WITHIN A COMPLEMENTARY POLYGONAL APERTURE IN SAID WORK PIECE FOR RESISTING RELATIVE ROTATION BETWEEN SAID ANCHOR MEMBER AND WORK PIECE, SAID HEAD SECTION HAVING AN AXIAL SUBSTANTIALLY CIRCULAR SCREW ACCOMMODATING BORE EXTENDING THERETHROUGH WHICH IS BONDED B A CIRCUMFERENTIALLY CONTINUOUS WALL SURFACE, SAID SHANK SECTION HAVING AN AXIAL SCREW ACCOMMODIATING PASSAGEWAY COMMUNICATING WITH AND EXTENDING COAXIALLY WITH RESPECT TO SAID BORE, A FIRST PAIR OF OPPOSITE OUTER SIDE SURFACES OF SAID SHANK SECTION INCLUDING PORTIONS DIVERGING FROM ADJACENT THE WORK ENGAGING SURFACE OF SAID HEAD SECTION AND PROVIDING SHOULDER MEANS SPACED AXIALY FROM SAID HEAD SECTION AND ADAPTED TO ENGAGE THE SIED OF A WORK PIECE OPPOSITE FROM THE SIDE ENGAGED BY SAID HEAD SECTION FOR RESISTING WITHDRAWAL OF THE ANCHOR MEMBER FROM SAID WORK PIECE, SAID SIDE SURFACES ALSO INCLUDING CONVERGING PORTIONS EXTENDING FROM ADJACENT SAID SHOULDER MEANS TOWARD A FREE