Injection mould for compact discs - uses replaceable thin cavity plates and its design ensures that constant width of air venting gap remains for any thickness of plate

摘要

Injection mould system has two mould tools and a means of fixing replaceable thin plates in the mould. These are held by the edge when lying against the fixed mould tool; a stop face is adjustable for the moving mould tool so that the thickness of the plate sets the closed position of the mould; and a radial gap is left between the plate and moving tool for venting regardless of the thickness of the plate used. ADVANTAGE - The layout is a simple soln. for the problems of compensating for varying thicknesses of plate, particularly in the production of compact discs, so that there is always a venting gap of constant width.