Tracking Global Threats with the Internet Motion Sensor

A container of heat-sealable plastic material, such as PVC, is made by folding a sheet of that material into V-shape and doubling back the vertex of the "V" to form a W-shaped profile, the infolded section or gore of the "W" being sealed except at one or two locations where rigid guide sleeves are inserted and are tightly gripped by the surrounding sheet portions. Each guide sleeve accommodates a hollow plunger for the withdrawal or introduction of fluids, the plunger having a pointed tip designed to pierce the container wall at the ridge of the gore defining the central peak of the W. A resilient annular lip at the outwardly projecting sleeve extremity coacts with two sawtooth-profiled annular grooves on the plunger to index the latter inextractably in a withdrawn position before the piercing step and thereafter in an advanced position so as to prevent leakage. A machine for making a series of such containers from a plastic strip by edge-sealing and transverse cutting includes a pair of sealing dies with semicylindrical recesses and means for feeding successive guide sleeves into pouches formed by these recesses between confronting sheet edges.