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

The Korean Society of Mechanical Engineers (대한기계학회)
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Investigation into Thread Rolling Characteristics of Subminiature Screws According to Thread Shapes

나사산 형상에 따른 초소형 나사 전조공정의 성형특성 고찰

  • Lee, Ji Eun (Dept. of Mechanical System Design Engineering, Seoul Nat'l Univ. of Science and Technology) ;
  • Kim, Jong Bong (Dept. of Mechanical and Automotive 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) ;
  • Ra, Seung Woo (Research Center, Seoul Metal Co. Ltd.)
  • 이지은 (서울과학기술대학교 기계시스템디자인공학과) ;
  • 김종봉 (서울과학기술대학교 기계자동차공학과) ;
  • 박근 (서울과학기술대학교 기계시스템디자인공학과) ;
  • 나승우 ((주)서울금속 기술연구소)
  • Received : 2016.05.31
  • Accepted : 2016.07.29
  • Published : 2016.11.01
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Abstract

Recent trends in miniaturization and lightness in portable electronics parts have driven developments in subminiature screws. This study aims to investigate the thread rolling process of a subminiature screw with an outer diameter and pitch of 1.0 and 0.25 mm, respectively. Finite element (FE) analyses were performed for the thread rolling process of symmetric and asymmetric screw threads. Through FE analyses, various process parameters, such as the horizontal and vertical die gap and the rolling stroke, were investigated in terms of the forming accuracy. The material flow characteristics in the thread rolling process of the symmetric and asymmetric screws were also discussed, and the relevant process parameters were determined accordingly. These simulation results were then reflected on real thread rolling processes, from which the symmetric and asymmetric screws could be formed successfully with allowable dimensional accuracy.

최근 전자제품의 소형화 및 경량화 추세에 따라 초소형 체결제품의 개발 필요성이 대두되고 있다. 본 연구에서는 이동통신기기 적용을 위한 초소형 나사(외경 1.0 mm 피치 0.25 mm)의 전조공정에 대한 연구를 수행하였으며, 특히 대칭 나사산과 비대칭 나사산의 성형을 위한 전조공정의 유한요소해석을 수행하였다. 유한요소해석을 통해 전조금형의 수평방향 간격, 수직방향 간격, 이동 거리 등의 공정변수가 성형된 나사산의 형상정밀도에 미치는 영향을 분석하였다. 또한 대칭 나사산과 비대칭 나사산에서 발생되는 재료 유동의 차이를 비교하고, 그에 따른 공정변수의 영향을 분석하였다. 상기 해석 결과로부터 도출된 공정변수를 실제 전조공정에 적용한 결과 대칭 나사산과 비대칭 나사산 모두 원하는 형상정밀도 내에서 성공적으로 성형될 수 있음을 확인하였다.

Keywords

References

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