Patent ID: 6854940

Claim:
A blind rivet to be mounted in a hole of a workpiece comprising: a. a rivet body having a cylindrical shank, closed at the top end and open at the opposite end with an external flange formed at the open end thereof; b. a mandrel disposed in the rivet body and having a stem extending outwardly therefrom to terminate in an axially ridged portion at the end thereof remote from the rivet body; c. the mandrel having a head clampingly disposed adjacent the closed end of the rivet body; d. a breakneck formed on the stem adjacent the head thereof; e. the rivet body has a first series of radial impressions crimped outwardly of the breakneck; and f. the rivet body has a second series of radial impressions crimped at a predetermined axial distance from the first radial impressions to form a radial gap between the rivet body and the stem of the mandrel to define a bent portion between the first crimp and the second crimp of the rivet body the bent portion having a constantly varying diameter between the first and second impressions.