Mechanical and adhesive charged blind fasteners have an annular one way
flat or O-ring seal mounted at one end of a cylindrical rivet body
sealingly engaged with an axially extending mandrel stem to provide a
torodial chamber. The body has radial adhesive-extruding openings
therethrough around which a vacuum may be established for initial adhesive
charging purposes. For charging, the seal is deflected by the force of a
flow of adhesive from a supply responding to the establishment of a
positive pressure differential between the supply and the exterior of the
body. With the torodial chamber opened, viscous adhesive readily flows
therein from the supply. After being filled, the vacuum is terminated and
the seal naturally recovers and closes the body to confine the adhesive
therein. Adhesive charging can be achieved by other mechanisms that
impress a load on the supply to effect seal opening.
