Expansible anchor for securing an object to a support structure

Claim 1

An expansible anchor for securing an object to a support structure comprising an expansion sleeve having a leading end portion and a trailing end portion and adapted for insertion in an anchoring hole of a support structure; an expander member at said leading end portion; an expander screw in form of a threaded rod-like member extending through said sleeve and having a front portion engaging said expander member for drawing the same into said sleeve to thereby expand the latter, a rear portion which extends outwardly from said trailing end portion and is adapted to extend through an object to be secured to the support structure, and an abutment portion forming an annular shoulder extending radially outwardly of said front portion and having an outer diameter equal to the outer diameter of said sleeve; a nut threaded onto said rear portion of said screw and arranged to engage said rear portion of said screw and cause the latter to turn in response to turning of said nut which results in drawing of said expander member into said sleeve; and a cap having concentric inner and outer annular wall portions and a transverse wall portion connecting said annular wall portions, said wall portions having respective first surfaces bounding a space for receiving said trailing end portion of said sleeve, and second surfaces opposite said first surfaces, the second surface of said outer annular portion having a diameter exceeding that of the anchoring hole of the support structure prior to cap insertion whereby said cap is frictionally retained in the anchoring hole against rotation and said first surfaces frictionally prevent said sleeve from rotating, said transverse wall portion being interposed between said trailing end portion and said annular shoulder of said expander screw so that said second surface thereof abuts said annular shoulder.