Plastic Syringe Set: Moulded Barrel and a Soft Polyethylene Piston

Four moulded parts make a plastic syringe with no rubber seal and no grease: a stiff barrel with a taper nozzle, a bell-shaped piston whose thin polyethylene lips seal against the wall, a slim plunger shaft, and a cap whose long sleeve guides the shaft so it cannot bend and tilt the piston (Adorján & Dávid, US 4,704,105, 1987). Mould one set of moulds per size for a set of syringes for hydraulic models. The piston figures are the patent's. Polypropylene, LDPE, the sizes and the mould making are ours. Not for medical use. The picture: Figs. 1-2.