Elastic element for a device for dispensing fluids or mixtures and method and mould for making said elastic element

A method for an injection molding an elastic element having a resilient, compressible tubular body with a spiral-shaped pattern extending in a longitudinal direction along an axis of the main tubular body, said method comprising the following steps:

• providing a mold suitable for injection molding comprising a hollow die having a fixed support and one or more movable dies and inserting a male punch along a longitudinal axis into said die in such a way as to define an interspace in a shape corresponding to that of an elastic element between said hollow die and said male punch, wherein the elastic element includes a plurality of first projections perpendicular to the longitudinal axis at one end of the elastic element and a plurality of second projections parallel to the longitudinal axis at an opposing end of the elastic element;
• injecting plastic material in a pasty state into said interspace;
• and
• removing said male punch by rotating the punch about the longitudinal axis,
• wherein during rotation of said punch at least one of said first projections and said second projections of said elastic element becomes engaged in a corresponding seat created in the fixed support, so that said elastic element cannot be rotated by said punch.