Injection moulding of closure slides for recording cassettes - using mathematical relationship for injection process parameters to give accurate dimensions of very thin components

摘要

U-shaped closure slide for a magnetic recording cassette is injection moulded with an injection cylinder having the relationship D2 = A x C x (M/=Pi) where D = injection cylinder dia. in mm; C = no. of slides made simultaneously in the mould; M = vol. of the slide in cm3; A = cylinder coefft.; A = 130-510. The material can be polyoxymethylene and the duration of the injection process 0.07-0.14 secs. The complete injection cycle can be 5-13 secs. with a value of A pref. 160-400mm. USE/ADVANTAGE - Useful for the accurate mfr. of thin components, e.g., slides for 3.5 inch floppy discs