National Nail Corporation

Jon Tanis

Roger C Bruins

A resilient molded pressure plate formed of polypropylene or the like is provided for a roofing nail in engagement with a sheet of roofing felt to increase the retention of the felt. The underside of the plate is concave in the undeflected form, and is provided with a central boss that limits the downward diaphragm deflection as a nail is driven through a central opening. The peripheral rim of the plate is serrated with concentric ridges disposed initially at progressively increasing distances from the plane of the outer ridge, proceeding radially inward. As the plate is deflected on driving of the nail through the central opening, these ridges come into coplanar relationship, providing the maximum intensity of engagement with the sheet of felt material.

Growing community of inventors

Jenison, MI, United States of America

Jon Tanis