Abstract: A drive system including a bit with a bit end configured to provide targeted frictional engagement with a fastener. The bit end has an outer leading wall tapered with respect to the bit end longitudinal axis at a leading wall angle selected from leading wall angle values ranging within a leading wall angle tolerance band and the fastener has an inner recess wall tapered with respect to the fastener longitudinal axis at a recess wall angle selected from recess wall angle values ranging within a recess wall angle tolerance band, wherein the leading wall angle values within the leading wall angle tolerance band and the recess wall angles values within the recess wall angle tolerance band do not overlap when the outer leading wall contacts the inner pilot recess wall at a targeted focal area to achieve a desired level of frictional engagement between the pilot end and the fastener.

Abstract: A drive system including a bit with a bit end configured to provide targeted frictional engagement with a fastener. The bit end has an outer leading wall tapered with respect to the bit end longitudinal axis at a leading wall angle selected from leading wall angle values ranging within a leading wall angle tolerance band and the fastener has an inner recess wall tapered with respect to the fastener longitudinal axis at a recess wall angle selected from recess wall angle values ranging within a recess wall angle tolerance band, wherein the leading wall angle values within the leading wall angle tolerance band and the recess wall angles values within the recess wall angle tolerance band do not overlap when the outer leading wall contacts the inner pilot recess wall at a targeted focal area to achieve a desired level of frictional engagement between the pilot end and the fastener.

Abstract: Disclosed is a screw head having a slot (2) in the upper surface of the screw head, an upper peripheral wall (9) of hexalobular planform extending down into the screw head, the upper peripheral wall (9) being parallel or near parallel to the axis of the screw, a sloping transition surface (15) extending downwardly and inwardly with respect to the lower edge of the upper peripheral wall (9), and a tapered recess (11) extending downwardly from the lower edge of the sloping transition surface (15), in which the dimensions of the screw head are such that when the screw head is engaged by a tool (6) having upper (16) and lower engagement (17) sections, there is a ‘stick fit’ between the surface of the tapered recess (11) and the external surface of the lower engagement section (17), and there is no engagement with the sloping transition surface (15).

Abstract: A screw, tool and a system for driving a screw that includes a screw and a corresponding tool is provided. The screw includes a screw head including a slot in the upper surface of the screw head, a tapered recess disposed downwardly of the slot in the screw. The tool includes an upper engagement section which fits within the slot, and a lower engagement section shaped to extend into the tapered recess with a contact surface of an external surface of the lower engagement section in an interference fit with the tapered recess when the upper engagement section is disposed within the slot. The contact surface has a shape which substantially matches any of a plurality of angular inclinations the surface of the tapered recess may have at the interference fit.

Abstract: Disclosed is a screw head having a slot (2) in the upper surface of the screw head, an upper peripheral wall (9) of hexalobular planform extending down into the screw head, the upper peripheral wall (9) being parallel or near parallel to the axis of the screw, a sloping transition surface (15) extending downwardly and inwardly with respect to the lower edge of the upper peripheral wall (9), and a tapered recess (11) extending downwardly from the lower edge of the sloping transition surface (15), in which the dimensions of the screw head are such that when the screw head is engaged by a tool (6) having upper (16) and lower engagement (17) sections, there is a ‘stick fit’ between the surface of the tapered recess (11) and the external surface of the lower engagement section (17), and there is no engagement with the sloping transition surface (15).

Abstract: The invention provides a screw head having a hexalobular slot (2) in the upper surface of the screw head, an upper peripheral wall (9) of hexalobular planform extending down into the screw head, the upper peripheral wall (9) being parallel or near parallel to the axis of the screw, a sloping transition surface (15) extending downwardly and inwardly with respect to the lower edge of the upper peripheral wall (9), and a tapered recess (11) extending downwardly from the lower edge of the sloping transition surface (15), in which the dimensions of the screw head are such that when the screw head is engaged by a tool (6) having upper (16) and lower engagement (17) sections, the lower engagement section (17) is tapered, and there is a ‘stick fit’ between the surface of the tapered recess (11) and the external surface of the lower tapered engagement section (17), and there is no engagement with the sloping transition surface (15).

Abstract: The invention provides a screw head having a hexalobular slot (2) in the upper surface of the screw head, an upper peripheral wall (9) of hexalobular planform extending down into the screw head, the upper peripheral wall (9) being parallel or near parallel to the axis of the screw, a sloping transition surface (15) extending downwardly and inwardly with respect to the lower edge of the upper peripheral wall (9), and a tapered recess (11) extending downwardly from the lower edge of the sloping transition surface (15), in which the dimensions of the screw head are such that when the screw head is engaged by a tool (6) having upper (16) and lower engagement (17) sections, the lower engagement section (17) is tapered, and there is a ‘stick fit’ between the surface of the tapered recess (11) and the external surface of the lower tapered engagement section (17), and there is no engagement with the sloping transition surface (15).

Abstract: The invention provides a screw head having a hexalobular slot (2) in the upper surface of the screw head, an upper peripheral wall (9) of hexalobular planform extending down into the screw head, the upper peripheral wall (9) being parallel or near parallel to the axis of the screw, a sloping transition surface (15) extending downwardly and inwardly with respect to the lower edge of the upper peripheral wall (9), and a tapered recess (11) extending downwardly from the lower edge of the sloping transition surface (15), in which the dimensions of the screw head are such that when the screw head is engaged by a tool (6) having upper (16) and lower engagement (17) sections, the lower engagement section (17) is tapered, and there is a ‘stick fit’ between the surface of the tapered recess (11) and the external surface of the lower tapered engagement section (17), and there is no engagement with the sloping transition surface (15).

Abstract: System comprising a crew and a tool (6) therefore, in which the screw head (1) with a slot (2), the slot (2) having a first recess (3) with an approximately straight-walled cross section, and the tool being provided with an engagement section (16) that is complementary to the first recess (3). The slot has a second recess (11) at the bottom of the first recess (3), with a smaller diameter than that of the recess (3), and the tool (6) is provided with a central point (17) that complements the second recess (11). The second recess (11) has a circular cross section and the central point (17) has a circular cross section.