한국산학기술학회논문지 (Journal of the Korea Academia-Industrial cooperation Society)

  • 제13권9호
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  • Pages.3815-3821
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  • 2012
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  • 1975-4701(pISSN)
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  • 2288-4688(eISSN)
한국산학기술학회 (The Korea Academia-Industrial cooperation Society)
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2 캐비티 LCD 사출품의 품질향상에 관한 해석 및 실험적 연구

Analytical and experimental study on the quality improvement of 2 cavity injection-molded LCD frame

  • Son, Jae-Hwan (Daegu Mechatronics & Materials Institute) ;
  • Jang, Eun-Sil (Daegu Mechatronics & Materials Institute) ;
  • Han, Chang-Woo (Division of Automobiles, Yeungnam College of Science & Technology) ;
  • Son, Jae-Yong (Department of Agricultural Engineering, National Academy of Agricultural Science) ;
  • Lee, Young-Moon (School of Mechanical Engineering, Kyungpook National University)
  • 투고 : 2012.06.20
  • 심사 : 2012.09.06
  • 발행 : 2012.09.30
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초록

LCD 프레임은 중 대형 TFT-LCD BLU의 기본형상을 유지시켜주는 중요한 부분이다. 중 대형 LCD 프레임을 효율적으로 생산하기 위해 1 캐비티에서 2 캐비티 사출 공정으로의 개선이 필요하다. 2 캐비티 금형 구조는 콤팩트하게 되었고 핫 런너 존이 증가되었기 때문에 사출온도를 조절하기 어렵게 되었다. 본 연구에서는 2 캐비티 사출성형공정으로 생산된 프레임에 대한 품질을 평가하기 위해서 유한요소해석 프로그램을 사용하여 사출해석을 수행하였다. 1 캐비티와 2 캐비티 공정에서 계산된 사출압력과 최대 변형량은 각각 41.13 MPa과 1.62 mm, 40.49 MPa과 1.66 mm이다. 1 캐비티 프레임의 측정된 최대 굽힘 하중, 표면거칠기가 140 N, 0.13 ${\mu}m$, 인데 비하여 2 캐비티 중 좌, 우 프레임의 측정값들은 209 N, 0.08 ${\mu}m$와 193 N, 0.10 ${\mu}m$이다. 열화상은 2 캐비티 금형 중 좌 우 금형 온도의 최대 표준 편차값은 $1.23^{\circ}C$임을 나타내고 있다. 시뮬레이션과 측정은 전체적으로 2 캐비티 사출공정의 프레임 품질이 1 캐비티 품질보다 나쁘지 않다는 것을 보여주고 있다. 그러나 2 캐비티 공정에서 프레임의 최대 굽힘 하중값은 1 캐비티 공정의 하중값보다 매우 증가되었다.

The LCD frame is an important part which supports the BLU of medium/large sized TFT-LCD. To produce it efficiently, it is necessary to achieve the molding process improvement from 1 cavity to 2 cavity system. Because 2 cavity mold is compact and its hot-runner zone is broadened, it is difficult to control the temperature on the mold. In this study, injection molding analysis on the frame in 2 cavity process with FEA(Finite Element Analysis) software is carried out to estimate its quality. The calculated injection molding pressures and maximum deflection in 1 and 2 cavity processes are 41.13 MPa and 1.62 mm, 40.49 MPa and 1.66 mm respectively. The measured maximum flexure load and surface roughness of the left and right frame of 2 cavities are 209 N and 0.08 ${\mu}m$, 193 N and 0.10 ${\mu}m$ while those in 1 cavity are 140 N and 0.13 ${\mu}m$. Thermal image shows that the maximum standard deviation of the temperature on left and right side of 2 cavity mold is $1.23^{\circ}C$. The simulation and measurement results show that the quality of the frame in 2 cavity injection molding process as a whole is not worse than that of 1 cavity system. But maximum flexure loads of the frame in 2 cavity process are far greater than that in 1 cavity process.

키워드

참고문헌

  1. Jacques, M.S., "An Analysis of Thermal Warpage in Injection Molded Flat parts Due to Unbalanced Cooling", Polymer Eng. and Science, Vol.22, No.4, pp. 241-247, 1982. https://doi.org/10.1002/pen.760220405
  2. Lam, Y.C. and Seow, L.W., "Optimzing flow in plastic injection molding", Journal of Materials processing Technology, Vol.72, pp. 333-341, 1997. https://doi.org/10.1016/S0924-0136(97)00188-X
  3. Lee, Y.U., "A Study on the Battery Case Injection Molding by CAE Analysis," J. of the korean Academic-Industrial Cooperation Society, Vol.12, No.1, pp. 55-61, 2011. https://doi.org/10.5762/KAIS.2011.12.1.055
  4. Min, B.H., "A study on quality monitoring of injection-molded parts", Journal of Materials Processing Technology, Vol.136, pp. 1-6, 2003. https://doi.org/10.1016/S0924-0136(02)00445-4
  5. Park, J.C. and Kim, B.H., "Automated Molding Design Methodology to Optimize Multiple Defects in Injection Molded Parts," Jnt'I J. of the korean Society of Precision Engineering, Vol.1, No.1, pp. 133-145, 2000.
  6. Choi, W.J., Sin, H.C., and Kwak, S.W., "Optimization of Processing Conditions in injection Molding Using Genetic Algorithm", The Korean Society of Mechanical Engineers(A), Vol.24, No.10, pp. 2543-2551, 2000.
  7. Shen, C.Y., Yu, X.R., Li, Q., and Li, H.M., "Gate Location Optimization in Injection Molding By Using Modified Hill-Climbing Algorithm", Polymer-Plastics Technology and Engineering, Vol.43, No.3, pp. 649-659, 2004. https://doi.org/10.1081/PPT-120038056
  8. Erzurumlu, T. and Ozcelik, B., "Minimization of warpage and sink index in injection-molded thermo plastic parts using Taguchi optimization method", Materials and Design, Vol.27, pp. 853-861, 2006. https://doi.org/10.1016/j.matdes.2005.03.017
  9. T. Kwon and etc trans., "Moldflow Design Guide", MunUnDang, pp.121-151, 2001.
  10. Son, J.H., Kim. Y.S., and Han. C.W., "A Quality Stability Estimation of Shock-absorber Tube for Automatic Drawer," J. of the korean Academic-Industrial Cooperation Society, Vol.12, No.7, pp. 2919-2924, 2011. https://doi.org/10.5762/KAIS.2011.12.7.2919
  11. Malloy, R.A., "Plastic Part Design for injection Molding: An Introduction", Hanser/Gardner Publishers, Inc., Cincinnati, pp.75-84, 1994.