Clamping clinch fastener
AssigneePenn Engineering & Manufacturing Corp.
InventorsMichael J. Mahoney, Robert P. Smith
Life of this patent
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Abstract
A clinch fastener with a single-element, unitary construction that does not require the preassembly of parts. The fastener provides a clamp load after installation and is fully formed by stamping the part from sheet metal. The fastener provides the necessary rigidity for a clinch attachment shank with the resilience of a head that will provide a residual clamp load to the attached panels. The fastener attaches two panels face-to-face by extending through aligned apertures in the panels. A shank undercut receives the cold flow of material from the second bottom panel while the panels are clamped against a resilient dome-shaped head of the fastener. The fastener may include a central axial well that receives the tip of a press punch during installation.
Claims13
A fastener, comprising:
- a dome-shaped head at a top end having a radially extending skirt with a downward extending periphery;
- a shank extending downward from the head, said shank having an elongate cylindrical upper portion and a shoulder;
- an undercut located immediately below the shoulder;
- an arcuate bulbous portion of the shank located immediately below the undercut at a bottommost end of the shank;
- and
- a central axial well extending from an opening at the top of the head to the bottom of the shank, said well having an internal pressing surface radially adjacent the undercut adapted to directly receive a pressing force from a punch.
Dependencies are inferred from the claim text.