Analyses of structural dynamic characteristics and end milling in a vertical machining center

금형 가공기의 엔드밀 가공 및 구조 동특성 해석

  • 이신영 (군산대학교 기계공학부) ;
  • 김성걸 (서울대학교 정밀기계설계공동연구소) ;
  • 이장무 (서울대학교 기계설계학과)
  • Published : 1997.03.01

Abstract

In a high speed and high precision vertical machining center, chatter vibration is easily generated due to unbalanced masses in rotating parts and changtes of cutting forces. In this paper, modal test is performed to obtain modal parameters of the vertical machining center. In order to predit the cutting force of endmilling process for various cutting conditions, a mathematical model is given and this model is based on chip load, cutting geometry, and relationship between cutting forces and the chip load. Specific cutting constants of the model are obtained by averaging forces of cutting tests. The interactions between the dy- namic characteristics and cutting dynamics of the vertical machining center make the primary and the secondary feedback loops, and we make use of the equations of system to predict the chatter vibration. The chatter prediction is formulated as linear differential-differene equations, and simulated for several cases. Trends of vibration as radial and axial depths of cut are changed are shown and compared.

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