대한기계학회논문집A (Transactions of the Korean Society of Mechanical Engineers A)

  • 제39권10호
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  • Pages.1021-1028
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  • 2015
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  • 1226-4873(pISSN)
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  • 2288-5226(eISSN)
대한기계학회 (The Korean Society of Mechanical Engineers)
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초소형 렌즈 사출성형시 냉각효율 향상을 위한 박판형 러너의 설계 및 해석

Design and Analysis of Shell Runners to Improve Cooling Efficiency in Injection Molding of Subminiature Lens

  • 윤승탁 (서울과학기술대학교 기계시스템디자인공학과) ;
  • 박근 (서울과학기술대학교 기계시스템디자인공학과)
  • Yoon, Seung Tak (Dept. of Mechanical System Design Engineering, Seoul Nat'l Univ. of Science and Technology) ;
  • Park, Keun (Dept. of Mechanical System Design Engineering, Seoul Nat'l Univ. of Science and Technology)
  • 투고 : 2015.06.11
  • 심사 : 2015.08.04
  • 발행 : 2015.10.01
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초록

최근 휴대폰용 카메라에 널리 사용되는 초소형 렌즈는 사출성형으로 생산되고 있다. 초소형 렌즈는 제품 크기에 비해 러너부가 상태적으로 큰 비중을 차지하는 특성이 있어 이에 특화된 금형설계 및 성형조건의 설정이 필요하다. 본 연구에서는 초소형 렌즈의 사출성형을 위한 박판형 러너구조를 제안하였다. 제안된 러너구조를 적용한 사출성형 공정의 전산모사를 수행하고, 해석 결과를 기존의 원통형 러너의 결과와 비교하였다. 해석 결과 박판형 러너의 경우 원통형 러너에 비해 냉각시간이 상당부분 절감되나 사출압은 다소 증가됨을 확인하였다. 또한 박판형 러너의 두께를 변화시켜가며 해석을 수행하여 유동특성과 냉각특성의 변화를 종합적으로 고려한 최적의 러너두께를 결정하였다.

Subminiature lenses are currently widely used in mobile phone cameras and are usually produced by injection molding. The lens molding process has the unique feature of a runner volume that is much larger than the part volume, and this feature should be considered when determining the mold design and molding conditions. In this study, a shell-type runner was proposed as an alternative to the conventional cylindrical runner used for lens molding. An injection molding simulation was performed by applying the proposed shell runner, and the simulation results were compared with those from the cylindrical runner case. It was found that the shell runner could considerably reduce the runner cooling time with only a slight increase in the injection pressure. The effect of the runner thickness was then investigated numerically in terms of the mold filling and cooling characteristics, from which an optimal runner thickness could be determined.

키워드

참고문헌

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피인용 문헌

  1. Three-Dimensional Thermoforming Analysis of an Inner Case with Three Cavities for Refrigerator vol.40, pp.5, 2016, https://doi.org/10.3795/KSME-A.2016.40.5.505