DOI QR코드

DOI QR Code

5축 절삭가공기 교육 중 2NC 헤드의 고강도 알루미늄을 적용한 스핀들 하우징의 극한 조건의 진동해석에 관한 연구

A Study on the Vibration Analysis of Spindle Housing with High Strength Aluminum of 2NC Head in Five-axis Cutting Machine Training

  • 이지웅 (영남이공대학교 기계공학과)
  • Lee, Ji Woong (Department of Mechanical Engineering, Yeongnam Technical School)
  • 투고 : 2022.03.25
  • 심사 : 2022.04.15
  • 발행 : 2022.04.30

초록

교육용으로 사용되는 피삭재(소재)는 SM20C, Al6061, 아크릴 등의 소재를 사용한다. SM20C 소재는 탄소강으로서 자격증 시험 및 기능경기대회에서 많이 사용되지만 산업현장에서도 많이 사용된다. Al6061 소재는 탄소강에 비하여 경도가 낮아지고 전성(연성)이 강한 소재이기에 공구의 구성인선이 많이 발생하는 소재라고 한다. 아크릴 소재를 이용하여 학생들에게 실습지도 하면 어느 부분에서 과다 절삭으로 인하여 진동이 발생하고 공구의 파손이 발생하는 소재이다. 이러한 과정에서 5축장비인 2NC헤드에게 가해지는 충격이 정밀도 제어에는 어느정도 영향을 줄 수 있는지 알아본다. 5축장비의 가장 취약한 부분은 AC축을 제어하는 헤드가 가장 약한 부분이라 할 수 있다. 이 부분의 정밀도 및 누적 공차가 발생할 경우 모든 제품의 정밀도가 떨어지는 현상이 발생한다. 따라서 2NC헤드의 핵심적인 부분, 스핀들 하우징은 Al7075 T6(미국 알코아사) 소재를 사용하여 진행하였다. 이 소재에서 작용되는 진동 및 절삭 과정에서 힘을 극한조건에서 유한요소 해석으로 적용되는 값을 밝혀 내고자 해석을 진행하였다. 이러한 해석 데이터를 활용하여 학생들이 5축절삭 보다 5축가공기의 구조를 보고 이해하는데 도움이 되기를 기대한다.

Materials used for education are materials such as SM20C, Al6061, and acrylic. SM20C materials are carbon steel and are often used in certification tests and functional competitions, but are also widely used in industrial sites. The Al6061 material is said to be a material that has lower hardness and stronger flexibility than carbon steel, so it is a material that generates a lot of compositional selection of tools. If students are taught practical training using acrylic materials, vibration occurs due to excessive cutting in some parts and damage to the tool occurs. In this process, we examine to what extent the impact on the 2NC head, which is a five-axis equipment, can affect precision control. The weakest part of the five-axis equipment can be said to be the weakest part of the head that controls the AC axis. When the accuracy and cumulative tolerance of this part occur, the accuracy of all products decreases. Therefore, the core part of the 2NC head, the spindle housing, was carried out using an Al7075 T6 (Alcoa, USA) material. In the process of vibration and cutting applied to this material, the analysis was conducted to find out the value applied to the finite element analysis under extreme conditions. It is hoped that this analysis data will help students see and understand the structure of 5-axis machining rather than 5-axis cutting.

키워드

참고문헌

  1. N. H. Kim, "Selection of the optimal machining condition for a high-hardness resin using the 5-axis machine," Journal of the Korean Society of Manufacturing Process Engineers, vol. 11, issue 5, pp. 29-34, 2012.
  2. S. H. Kim, "Machining precision of 5-axis and 3-axis with rotating table machining center," Master's thesis, Graduate School of Engineering, Incheon National University: Mechanical Engineering, February 2021.
  3. S. G. Kim, J. H. Kim, S. H. Kim, and J. W. Youn, "Design optimization of the rib structure of a 5-axis multi-tasking functional machine tool considering the static stiffness," Journal of the Korean Society of Manufacturing Technology Engineers, vol. 25, issue 5, pp. 313-320, 2016. https://doi.org/10.7735/ksmte.2016.25.5.313
  4. J. S. Kim, "A study on design optimization of 5-axis multi-tasking machine tools considering static and dynamic stiffness," Master's thesis, Graduate School of Mechanical Engineering, Mechanical and Automotive Engineering, Daegu University, August 2021.
  5. S. K. Kim, "A study on the static and dynamic stiffness prediction of a 5-axis multi-functional machining center with the finite element analysis," Master's thesis, Daegu University: Mechanical Engineering, Mechanical and Automotive Engineering, 2015.
  6. J. P. Hong, B. C. Gong, S. D. Choi, H. J. Choi, and D. S. Lee, "Study on structure design of high-stiffness for 5 - axis machining center," Journal of the Korean Society of Manufacturing Process Engineers, vol. 10, no. 5, pp. 7-12, 2011.
  7. H. J. Choi, C. W. Park, E. S. Jang, C. H. Kim, and S. D. Choi, "Design of high speed spindle for 5-axis machining equipment equipped with piezo-electric load sensoring," The Korean Society of Manufacturing Process Engineers, vol. 10, no. 5 , pp. 20-25, 2011.
  8. K. I. Lee, "Sphericity evaluation and measurement of the geometric errors for a five-axis machine tool," Doctor dissertation, Graduate School of Mechanical Engineering, Kyungpook National University, 2013.
  9. J. B. Park, "A study on the structure design and geometric error calibration of a large gantry type 5-axis machine tool," Master's thesis, Graduate School of Chungcheongbukdo University: Mechanical Engineering (Hospital), August 2013.
  10. J. S. Park, "A study on the geometric error correction of rotating shaft of 5-axis machine tool using cross-shaped calibrator," Master's thesis, Graduate School of Dankook University: Mechanical Engineering, Production and Control, February 2020.
  11. H. C. Lee, "Integrated analysis and design of interlocking control system for 5-axis CNC machine tools," Master's thesis, Graduate School of Dankook University: Mechanical Engineering and Mechanical Engineering, February 2008.