Study On The Effect Of Initial Grinding Position Of The Two-Parallel Manipulator On The Helical Drill Cusp

In mechanical machining,drilling plays a very important role,so the higher requirement is put forward when drilling tools are selected.The grinding of helical twist drill on two-parallel manipulator has advantages of a good S-shape,smaller drilling force and higher drilling accuracy.However,in the actual grinding process,the span between the apex of the grinding point and the highest point of the end face of the grinder is manually controlled,which is called initial grinding position,and a small change has a significant effect on the actual grinding results,especially the chisel edge.The chisel edge is the main part of the helical drill cusp,the helical drill cusp is the main working part of twist drill,so the effect of initial grinding position on the helical drill cusp is studied in this paper.The main contents of this paper are as follows:(1)On the basis of consulting relevant domestic and foreign literatures,the movement and kinematics simulation of the two-parallel manipulator are studied;The mathematical model of the rear cutter surface and the front flank face is established,in which the rear cutter surface includes the core part and the outer part of the drill core.The four structure parameters of the helical drill cusp are determined,and the relationship between the structure parameters helical drill cusp and the grinding parameters of the grinding method is established;(2)The influence of grinding position on the structure parameters of helical drill cusp is studied.The mathematical model of rake angle,rear angle and chisel edge structure of twist drill is resolved,and the influence of grinding position on the rake angle and rear angle of the chisel edge and the shape of the chisel edge is studied;(3)Based on the 3D model of twist drill,the drilling performance of twist drill is analyzed by finite element software;The effect of different grinding positions on the equivalent stress of the helical drill cusp,the effect of drilling accuracy,the mode analysis of twist drill and the influence of grinding position on the natural frequency are all studied.And the influence of grinding position on drilling force and torque of the twist drill is also studied;(4)The GUI interface is made,so that the grinding parameters of the manipulator are calculated quickly.The grinding experiment is carried out on the two-parallel manipulator,and the grinding test of the helical drill cusp after grinding is carried out.After studying the effect of different initial grinding positions of the two-parallel manipulator on the helical drill cusp,we find that a certain initial grinding position can improve the structure of the helical drill cusp and also improve the drilling performance of the twist drill,so that the grinding theory of helical drill cusp on two-parallel manipulator is perfected.