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http://dx.doi.org/10.7736/KSPE.2015.32.11.961

Development of Injection Mold for Subminiature Lenses Using Shell Runners Containing Multiple Holes  

Yoon, Seung Tak (Department of Mechanical System Design Engineering, Seoul National University of Science and Technology)
Park, Keun (Department of Mechanical System Design Engineering, Seoul National University of Science and Technology)
Publication Information
Journal of the Korean Society for Precision Engineering / v.32, no.11, 2015 , pp. 961-968 More about this Journal
Abstract
This study aims to develop an efficient mold structure for the injection molding of a subminiature lens, using shell-type runners instead of traditional cylindrical runners. While the shell runner has the advantage of shorter cooling time due to its thinner geometry, this smaller thickness causes an increase in injection pressure. In this study, the design of the shell runner was modified to contain multiple holes for the purpose of reducing injection pressure. Numerical analyses were performed for shell runners of various hole-shapes, and the resulting filling and cooling characteristics were discussed; the rhombic hole showed the best result for both filling and cooling characteristics. Subsequently, injection molding experiments were performed using an injection mold fabricated based on the rhombic design. The lens parts were successfully molded with highly-reduced cycle time and without degradation of part quality.
Keywords
Injection molding; Subminiature lens; Shell runner; Multiple hole runner; Numerical analysis;
Citations & Related Records
Times Cited By KSCI : 9  (Citation Analysis)
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