Abstract: A fastener is described having a head formed with a recess which accommodates a square head driver, symmetrical drivers, such as PHILLIPS™ style drivers, asymmetrical style cross head drivers, such as POZIDRIV® style drivers, and combination square and cross drivers without compromising performance of the drivers.

Abstract: Recessed head fasteners are provided with a configuration by which the force applied by the blades of the driver to the recessed wings is applied at the radially outer regions of the wings. The wings of the fastener recess may be provided with torque pads at the outer regions of the wings adapted to engage the outer portions of the driver blades. The torque pads may be defined by relieved regions on the drive walls of the recess wings. The relieved regions are formed to avoid contact with the driver blades. Stabilizing ribs also may be defined at the radially inward regions of the drive walls. A recess engageable driver may include a plurality of radially extending ribs configured to promote engagement of the ribs with the most radially outward regions of the recess drive walls. The driver and the recess are compatible with each other as well as with otherwise corresponding conventional recesses and drivers that do not incorporate the invention.

Abstract: Recessed head fasteners are provided with a configuration by which the force applied by the blades of the driver to the recessed wings is applied at the radially outer regions of the wings. The wings of the fastener recess may be provided with torque pads at the outer regions of the wings adapted to engage the outer portions of the driver blades. The torque pads may be defined by relieved regions on the drive walls of the recess wings. The relieved regions are formed to avoid contact with the driver blades. Stabilizing ribs also may be defined at the radially inward regions of the drive walls. A recess engageable driver may include a plurality of radially extending ribs configured to promote engagement of the ribs with the most radially outward regions of the recess drive walls. The driver and the recess are compatible with each other as well as with otherwise corresponding conventional recesses and drivers that do not incorporate the invention.

Abstract: Recessed head fasteners are provided with a configuration by which the force applied by the blades of the driver to the recessed wings is applied at the radially outer regions of the wings. The wings of the fastener recess may be provided with torque pads at the outer regions of the wings adapted to engage the outer portions of the driver blades. The torque pads may be defined by relieved regions on the drive walls of the recess wings. The relieved regions are formed to avoid contact with the driver blades. Stabilizing ribs also may be defined at the radially inward regions of the drive walls. A recess engageable driver may include a plurality of radially extending ribs configured to promote engagement of the ribs with the most radially outward regions of the recess drive walls. The driver and the recess are compatible with each other as well as with otherwise corresponding conventional recesses and drivers that do not incorporate the invention.

Abstract: A fastener is constructed having four thread zones constructed over the length of the fastener, from the head to the tip, namely a ridged cylindrical holding zone, a ridged cylindrical transition thread forming zone, a rectilobular tapered thread forming zone, and a rectilobular alignment zone. The pitch cross section of the thread varies in each zone.

Abstract: A fastener has multiple secondary threads intertwined with a primary thread installable in a thermoplastic workpiece. A method and die are arranged for fabricating such a fastener. The fastener comprises a threaded shank portion having a primary thread of a desired form and a driver head attached thereto. At least one secondary thread is intertwined with the primary thread. In accordance with one embodiment of the invention, an outer surface of the fastener may be heated to a preselected Curie temperature during the installation of the fastener into a workpiece. The preselected Curie temperature enhances the flow of the thermoplastic material around the fastener while the fastener is being installed in the workpiece. A coating material having a particular desired Curie temperature may be applied to the fastener to produce desired driving characteristics.

Abstract: A thread-forming fastener and method of installation thereof are provided for use with a workpiece constructed of a thermoplastic material. The fastener includes a threaded shank having a thread of desired form and a driver head portion. A metallic coating of a predetermined composition is applied to the threaded shank. The composition of the coating is selected for its effective Curie temperature for heating the fastener during application of the fastener to the thermoplastic workpiece. The heated surface enhances plastic flow of the thermoplastic material during thread forming and effectively reduces the required drive torque for thread forming by the fastener while increasing the holding torque. The fastener is preferably also formed with a spaced thread defining an unthreaded surface portion running adjacent to the thread at substantially the root diameter of the thread.

Abstract: A blank and fastener formed from the blank for a thread-forming fastener which provides axially aligned driving. A tip portion of the blank is formed in a conical shape at an oblique angle to the shank portion of the blank. The blank formed as such is then formed with threads, however, the tip portion is formed with threads only about a portion of its outer surface. The resulting threaded fastener forms threads on an inside surface of a pilot hole in a workpiece in which it is inserted. The threaded fastener so formed minimizes driving effort and maintains proper alignment when the fastener is initially inserted and driven into an unthreaded pilot hole in a workpiece and also prevents cross-threading when the fastener is removed and reinserted into the workpiece.