Clamping Clinch Fastener
AssigneePenn Engineering & Manufacturing Corp.
InventorsMichael J. Mahoney, Robert P. Smith
Life of this patent
Estimating the term…
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.
Claims17
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 a shoulder;
- an undercut located immediately below the shoulder;
- an arcuate bulbous portion of the shank located immediately below the undercut at a bottom-most 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.
An assembly, comprising;
- a first top panel and a second bottom panel positioned face-to-face, each with an aligned aperture extending through opposite sides of the panels;
- a fastener extending through said apertures, said fastener having a head with a skirt in contact with a top side of the first panel and having a shank rigidly affixed to the second panel;
- and,
- wherein the resilience of the skirt applies a residual clamp load to the panels joined thereby.
The combination of a punch and a fastener, comprising:
- a press punch having a pressing surface shoulder and a tip extending downward from the pressing surface shoulder;
- and
- a fastener having a head and a central axial well extending downward from an opening at the top of the head, said tip of said punch occupying said well while said pressing surface shoulder of the punch contacts the fastener head.
Dependencies are inferred from the claim text.