Abstract: A primary cell separator basket is formed from sheet material folded upon itself to form a basket bottom at the fold and bonded along margins in face to face contact extending from the fold. One or both sheet faces between the bonded margins are crowned outwardly to preform the basket and open its top. Basket preforms can be made in strips by longitudinally folding strip sheet material, crowning the material at intervals along the strip length and bonding the material in face to face relationship transverse of the strip length along the strip length in regions which fall between the crowns.

Abstract: A system of forming and manipulating primary cell separator basket preforms produced in strip form and tandem relationship with a dentent associated with each preform, e.g., a transverse slit in the strip for each preform displaced so its edge is outstanding from the generally flat strip. The preforms are fed to forming and insertion equipment by guiding the strip into alignment with a cut-off which is arranged to sever the lead preform and into alignment with a forming and insertion mandrel path of travel, engaging a detent on the strip with a dog and advancing the dog and strip along the path to present the lead preform for cut-off, opening and mandrel insertion. The severed preform is supported and compressed transversely between a support member having a groove to embrace a side portion of the preform and the dog or dog and cut-off blade so that it is opened and restained to receive the forming and insertion mandrel.

Abstract: A primary cell separator basket is formed from sheet material folded upon itself to form a basket bottom at the fold and bonded along margins in face to face contact extending from the fold. One or both sheet faces between the bonded margins are crowned outwardly to preform the basket and open its top. Basket preforms can be made in strips by longitudinally folding strip sheet material, crowning the material at intervals along the strip length and bonding the material in face to face relationship transverse of the strip length along the strip length in regions which fall between the crowns.