INJECTION MOULDS FOR CONTACT LENS PRODUCTION Russian patent published in 2011 - IPC B29C33/00 

FIELD: process engineering.

SUBSTANCE: set of invention relates to injection moulds for production of seamless contact lenses Proposed injection mould comprises front and rear halves. Front half makes a first article with central curved part with concave surface, convex surface and round circular edge. Note here that said first article has axis of symmetry of concave surface, first continuous circular-edge conical seam running upward from circular edge in the plane located some 75-85 degrees relative to plane perpendicular to axis of symmetry of said concave surface; first continuous shoulder with first conical seam running radially outward from first conical seam; circular flange made integral with said first shoulder running radially outward from concave and convex surfaces in the plane perpendicular to axis of concave surface. Mould rear half makes second article with central curved part with concave and convex surfaces. Note here that second article has axis of symmetry of convex surface, circular edge around convex surface, second conical seam running upward from circular edge in the plate locates about 75-85 degrees relative to axis of symmetry of convex surface; second shoulder continuous with second conical seam and running radially outward from second conical seam; circular flange made integral with convex and concave surface in the plane perpendicular to axis of symmetry of convex surface and running radially outward from said surfaces.

EFFECT: minor displacements of mold half, uniform edges of contact lenses.

9 cl, 12 dwg