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US 4,362,042 AGranted
Method of forming a fastener
AssigneeThe Lamson & Sessions Co.
InventorGlendon L. Crow, Jr.
Life of this patent
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AssigneeThe Lamson & Sessions Co.
InventorGlendon L. Crow, Jr.
Estimating the term…
An improved method of forming a fastener having a head and a shank includes the step of heating one end of a piece of barstock. A ring is then telescopically slid onto the cold end and moved toward the hot end of the barstock. Due to thermal expansion of the hot end of the barstock, the ring interferes with the hot end of the barstock. The ring is then engaged by a pair of dies and the barstock is forced further through the ring to accurately position it relative to the ring. The dies are then pressed against the barstock and the ring to grip the barstock and hold it against axial movement relative to the ring. The dies cooperate with the ring to form a die cavity. The hot end of the barstock extends into the die cavity. A header hot works the metal of the barstock to press it against an end surface of the ring and against side surfaces of the dies to shape the head end of the fastener. The header is then withdrawn, the dies are separated and the ring is removed from the shank of the fastener.
A method of forming a fastener having a head end portion and a shank portion, said method comprising the steps of providing a longitudinally extending workpiece having a uniform transverse cross sectional area throughout its length, heating an end portion of the workpiece so that the workpiece has a relatively hot end portion and a relatively cold end portion, said step of heating the workpiece including the step of increasing the transverse cross sectional area of the relatively hot end portion of the workpiece, providing a ring having a central opening with an area which is greater than the transverse cross sectional area of the cold end portion of the workpiece and less than the transverse cross sectional area of the hot end portion of the workpiece, effecting axial movement between the ring and workpiece with the ring circumscribing the relatively cold end portion of the workpiece, interrupting axial movement between the ring and workpiece by impacting engagement of the ring and the relatively hot end portion of the workpiece, applying force against the relatively hot end portion of the workpiece while holding the ring and workpiece against axial movement relative to each other to form the head end portion of the fastener, and thereafter effecting axial movement between the ring and the workpiece to disengage the ring from the shank portion of the fastener.
A method of forming a fastener having a head end portion, said method comprising the steps of telescopically placing a ring on a longitudinally extending workpiece with a first end portion of the workpiece extending axially outwardly in a first direction from the ring and a second end portion of the workpiece extending axially outwardly in a second direction from the ring, gripping both the ring and the first end portion of the workpiece with a plurality of die sections to hold the ring against axial movement relative to the workpiece, said step of gripping both the ring and the first end portion of the workpiece with a plurality of die sections including effecting relative movement between the die sections to abuttingly engage a longitudinally extending side surface of the first end portion of the workpiece and a side surface area of the ring with the die sections, said step of effecting relative movement between the die sections including forming a die cavity which circumscribes the second end portion of the workpiece and which is at least partially defined by surfaces on the die sections and ring, applying force against the second end portion of the workpiece to shape the second end portion of the workpiece in the die cavity against surfaces on the die sections and ring to form the head end portion of the fastener while gripping both the ring and the first end portion of the workpiece with the die sections, thereafter, effecting relative movement between the die sections to separate them from both the ring and the workpiece, and removing the ring from the workpiece.
A method of forming a fastener having a head end portion and a shank portion, said method comprising the steps of heating a first end portion of a longitudinally extending workpiece, a telescopically placing a ring on the workpiece after heating the first end portion of the workpiece, said step of telescopically placing a ring on the workpiece including the steps of axially aligning the ring with a second end portion of the workpiece and moving the ring axially along the workpiece from the second end portion of the workpiece toward the heated first end portion of the workpiece, gripping the ring and workpiece with a plurality of die sections to hold the ring and workpiece against axial movement relative to each other, said step of gripping the ring and workpiece being performed with the heated first end portion of the workpiece extending outwardly from the ring into a die cavity which is at least partially defined by the ring and the plurality of die sections and which has a configuration corresponding to the configuration of the head end portion of the fastener, applying force against the heated first end portion of the workpiece to shape the heated first end portion of the workpiece in the die cavity against the ring and die sections while holding the ring against axial movement relative to the workpiece with the die sections to form the head end portion of the fastener on one side of the ring with the shank portion of the fastener extending through the ring, disengaging the workpiece and ring from the die sections, and removing the ring from the shank portion of the fastener.
Dependencies are inferred from the claim text.