Improved method for calculating the cutting force of end milling with helical tools
DOU Wei1, YUAN Sheng-wan2, HE Xiao-cong1
1.Faculty of Mechanical and Electrical Engineering, Kunming University of Science and Technology, Kunming, 650500;
2.Shenji Group Kunming Machine Tool Company Limited, Kunming, 650203
It is necessary to determine the cutting forces at each time step for solving milling process dynamic equations. Usually, the integral of the cutting force of helical tool is approximated as follows: the tool is first divided into element disks, and then the elementary forces on each element disk are calculated as a corresponding straight teeth tool in turn, and finally the total cutting force is approximated by summing up all the elementary forces. This approximation approach was not only is timeconsuming but also causes errors. By variable substitution, the switch function of the cutting zone was eliminated from the cutting force integrand, and the integral limits were replaced by the position angle of the cutting edge entering the cutting zone. Then, the analytical expressions for cutting forces of helical tools were obtained, which simplifies the calculation of the milling force, thus can improve the efficiency of solving the dynamic equations for the belical tool milling. The simulation results show that the computational cost of solving a helical tool milling dynamic equation is equivalent to solving that of a straight teeth tool, and without introducing the tool axial discretization errors.
窦炜1,袁胜万2,何晓聪1. 一种改进的螺旋齿铣刀立铣切削力计算方法[J]. 振动与冲击, 2018, 37(10): 181-186.
DOU Wei1, YUAN Sheng-wan2, HE Xiao-cong1. Improved method for calculating the cutting force of end milling with helical tools. JOURNAL OF VIBRATION AND SHOCK, 2018, 37(10): 181-186.
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