Patent ID: 7329077

Claim:
A fastener apparatus for securing a workpiece, said fastener apparatus comprising a frusto-hemispherical head and shank appended thereto, said frusto-hemispherical having a body comprising a substantially extended flat top surface a curved outer surface and a peripheral edge, which incorporates a seal seating zone, said head further having a downwardly-appending lip portion extending from said curved outer surface and defining an annular recess within said body creating a leading edge as a shallow ramp for changing sideways and shearing energy of snow and ice into a downward force energy as it rides up said ramp causing snow to ride over and split around the sides of said head, said annular recess having a substantially flat upper surface and substantially vertical sidewalls transitioning from said substantially flat upper surface to said downwardly-appending lip portion, said lip portion having a curved outer edge creating the seal seating zone and a curved lower edge, a series of locking teeth adapted to resist loosening of said fastener from said workpiece, each of said locking teeth having a first end being substantially vertical at said shank and gradually curving to being substantially horizontal within said annular recess at their second end and a midpoint wherein said locking teeth are flared at an approximately 45-degree angle to said first and second ends which is equal to the lowest portion of the outer rim, said shank having a series of threads for engaging said workpiece and drawing said frusto-hemispherical head thereto, said threads extending along said shank toward said head such that a last thread proximate said frusto-hemispherical head cuts into one side of said looking teeth and an annular gasket located within said annular recess, said recess and gasket being sized such that when said fastener apparatus is fully secured to said workpiece, a first portion of said gasket protrudes from said frusto-hemispherical head to provide a first seal, a second portion of said gasket resides and is compressed between and surrounding said curved lower edge of said lip and said workpiece to provide a second seal and a third portion of said gasket remains within said annular recess to provide a third seal.