Patent ID: 7762034

Claim:
A method for securing two adjacent layers of a sheet material to each other comprising: providing a first layer of metal having first and second faces; providing a second layer of metal having third and fourth faces; bringing the second face of the first layer into face-to-face relationship with the third face of the second layer; lancing a generally elongated strap out of both the first and second layers such that the straps have ends that remain attached to their respective layers and sides that are separated from their respective layers, the straps having midsections that are displaced such that both the first and second faces of the midsection of the strap in the first layer are displaced past the first face of the first layer, while the third face of the midsection of the strap in the second layer is displaced past the first face of the first layer and the fourth face of the midsection of the strap in the second layer is displaced between the first and second faces of the first layer; swaging the lanced strap such that the midsection of the strap in the first layer is enlarged in width and the midsection of the strap in the second layer is deformed into the first layer.