A PUMP MADE OF PLASTIC FOR DISPENSING PRODUCTS FROM CONTAINERS

摘要

An all plastic pump for liquids (1; 300) to be applied to a container, comprises a cylindrical chamber (13; 330) communicating with said container through a feeding hole (14; 240); at least one piston (12; 320) axially sliding within said cylindrical chamber (13; 330); retaining valvular means; at least one elastic bellows (40; 500; 800) and having its lateral surface (50; 600) in the shape of a spiral (80; 510) and incorporates a spring (63) made of plastic realized in a single piece with the bellows itself, the turns of which are arranged in correspondence with the contraction areas of the spiral (80; 510), suited to realize a protruding stiffening rib in respect of the external surface of the spiral.