| 主权项 |
1. A blind rivet assembly, the blind rivet assembly comprising a hollow rivet body including an elongated shank that extends coaxially to a longitudinal center axis of the blind rivet and has a bore, a flange extending radially at one end of the shank, and, at the opposite end of the shank, a foot end and located in the bore of the rivet body, a mandrel that has a mandrel shank, a drawing end projecting out of the flange of the rivet body that can be separated from the mandrel shank, and a mandrel head that stands in operative connection with a foot end of the rivet body in order to transmit a force to the rivet body during setting of the blind rivet, the shank of the rivet body has a first section adjoining the flange and, adjacent thereto and extending to the foot end, a second section, wherein the first section defines an original cylindrical shape, but with a plurality of spaced apart, longitudinally extending flat deformations of the original cylindrical shape separated by undeformed longitudinal portions substantially retaining corresponding portions of the original cylindrical shape, and wherein the strength of the first section of the shank is increased with respect to the strength of the second section by the spaced apart flat deformations as a result of plastic deformation via cold forming the flat deformations so that the outside diameter of the first section does not increase or increases only slightly during rivet setting, and wherein the flat deformations of the hardened section are depressions, wherein the second section of the shank has a barrel-like shape that curves outward, a mandrel head includes an annular and angled recessed contact surface engaging a blind end of the rivet body when set, and the mandrel head remaining secured to the rivet body after being set. |
