Cuvette belts and manufacture of same

Claim 1

In a forming press apparatus in the manufacture of cuvette belts by cold forming plastic strip material with a series of regularly spaced transverse elongated pockets, said apparatus including: first and second die members respectively defining first and second clamping surfaces and having openings formed in both said clamping surfaces corresponding to the positions of said pockets, a plurality of forming punches mounted in said openings in said first clamping surface and movable through said openings in said second clamping surface with said punches spaced within said openings in said second clamping surface, means for driving said clamping surfaces together to clamp said strip material therebetween. means for advancing said forming punches from within said openings in said first clamping surface through said openings in said second clamping surface, after said surfaces have come together, to deform said strip material to form said pockets in the strip material by interaction between the ends of the punches and the edges of the corresponding openings in the second clamping surface, and means for inhibiting stretching of the strip material over the end surfaces of said punches, said punches being spaced within the corresponding openings in the second clamping surface whereby the strip material is in a free, unsupported state between the inner edge of each opening in the second clamping surface and end of the associated forming punch when the latter is advanced through said opening so as to permit stretching of said strip material to form said pockets, the ends of the forming punches being convexly radiused to form the bases of the pockets with approximately flat profiles across their width in the direction along the length of the strip.