| 簡 介： |
While the transfer from filling to packing is particularly crucial during
injection molding, the transfers from packing to holding and holding to screw
recovery also significantly affect part quality. In this study, the control of the transfer
from holding to screw recovery, that is the control of the end-point of the holding
phase, was examined. The holding end-point control by time, cavity pressure and
cavity temperature were presented. The purpose of this study was to validate the
feasibility of the control methods of holding end-point by cavity pressure and cavity
temperature. The qualities of injection-molded parts, weight, will serve as measures to
probe their process capabilities. Recently found to be a good indicator of product
quality, both cavity pressure and temperature profiles are applied here to obtain more
precise control. Change of mold temperature was specially considered. After the
experimental verification is conducted, the results reveal that the innovative holding
end-point control by cavity temperature yields a more uniform product weight with
mold temperature. It proved that the holding end-point control by cavity temperature
can be used to obtain the optimum holding time and accommodate the product weight
to the change of mold temperature, which is the other holding control methods cannot
obtain. |
