Papers by Author: S.J. Hu

Abstract: In this paper, a new mathematical model and grinding method of ball-end milling cutter are proposed, based on the orthogonal spiral cutting edge curve. The movements of grinding wheel and ball-end milling cutter are presented while grinding rake face. In order to grind conveniently and avoid interference, a conical wheel is also designed and employed to grind the rake face of ball-end milling cutter on a grinder. In order to improve the machining characteristics of ball-end milling cutter, the model of rake face with equal rake angle is established. The software of ball-end milling cutter is developed to design and optimize different shapes of rake face. Furthermore, the simulation analysis on rake face with equal rake angle is carried out to confirm the validation of the mathematical models.

Abstract: Micro-drills are becoming more and more important in precision and micro fabrications. They have been widely used in applications, e.g., precision and micro drilling. In this paper, a novel method is advanced and used for regrinding of chisel edges of helical micro-drills. In this method, a geometric model is established for the chisel edge regrinding. Based on the kinematic relationship of regrinding, the model simplifies machine movement so as to facilitate an easy operation. Computer simulation is applied to the regrinding process of the micro-drills. The results demonstrate that the proposed method is effective in regrinding chisel edges, which allows for a more reasonable distribution of the angles along the chisel edge of a drill, and enhances the drilling performance.

Abstract: In this paper, the characters of the 5-axes NC grinding machine for the drill point MK6335 are introduced. The attributes of Ni Zhifu drill (Chinese multi-facet drill-CMFD) are stressed. The sharpening key technology for the Ni Zhifu drill point in this grinding machine is stated. By using the grinding machine and the key technology, the CMFD can be ground accurately. After ground, the geometric angle error of the drill point is less than 1 degree.