| 摘要 |
Method and apparatus for making strips of expanded lead suitable for making bottom-border-bearing battery grids. The finished grid has a current-collecting header and bottom border of unexpanded strip and a reticulated portion, between the header and border, comprising expanded strip forming a plurality of paste-retaining cells bounded by skeletal elements and nodes. The skeletal elements and nodes extend in opposite directions through the paste from substantially one face of plate to the other and the nodes are twisted and partially flattened so as to have plateaus on the nodes which lay in planes parallel to the principal planes of the pasted plate. A ribbon or strip of lead is fed lengthwise through a gauntlet of dies and cutters and expanded from its longitudinal edges to form two reticulated portions and a central unexpanded portion. The initial cut taken from the edge slits, but does not substantially stretch, the metal. The unstretched metal forms a bottom border of the grid. A border straightener means attached to one of the dies engages the border about midway through the gauntlet to prevent deleterious curling of the reticulated portion in the expander. The fully expanded strip has a gull-winged configuration viewed headon, which wings are subsequently folded down by plow and roller means so as to be in substantially the same plane as the unexpanded portion. The reticulated portions are subsequently uniformly stretched in a direction perpendicular to the central portion and finally rolled to twist and flatten the nodes joining the skeletal elements. |
