METHOD AND DEVICE FOR INJECTION MOULDING FLAT OPTICAL DATA SUPPORTS WHICH HAVE A PRECISE WEIGHT

摘要

The novel invention provides for the controlled correction of possible quantitative errors in the production of optical data supports. The cavity of the mould is only partially filled prior to the stamping phase. It is the subsequent stamping that is used to complete the filling process by moving one mould half. In the first phase of stamping or compressing the melt, the pressure is detected in defined positions of the moulds or at a defined point in time and any deviation from a predetermined set pressure value is corrected by the immediate introduction of a movement change in the stamping process. By acting on the pressure conditions in the mould cavity, it is possible to influence the backflow before the sprue is set, in terms of a set weight value of the finished data support.