Papers by Keyword: Path Curves

Abstract: Polycrystalline diamond, (PCD) is currently used in the industry for cutting tools of difficult-to-machine materials because of its superior characteristics such as hardness, toughness and wear resistance. But the PCD material is difficult to machine due to its above properties. Before making the PCD blank in varies tools, the lapping process is essential and necessary. The lapping quality depends heavily on the parameters. Therefore it is of great significance to study the path and velocity of lapping process for ensuring the lapping quality and uniform wear of abrasive disk. In this paper, on the basis of kinematics and geometry principle, the path equation was established. The complicated lapping process can be converted into two rotation movements, i.e. the movement of part against the center of lapping disk and rotation of fixture around its center. The relative path and relative velocity of random point of the part against abrasive disk were also analyzed and calculated. The computer simulation software was developed for figuring the path curves and instantaneous velocity of the lapping process. The results show that the abrasive disk can wear uniformly and the lapping quality can be raised. The application of computer simulation software provides the possibility to analyze the lapping principles, which is a simple, convenient and effective method.

Abstract: The precise face grinding and lapping technology with abrasive or abrasive tool has been widely used in the field of the precise manufacture and ultraprecise manufacture. It has become an essential technology in the manufacture of many components. The planetary lapping machine is typical equipment for face grinding or lapping process. And the relative motions between the workpieces and grinding wheel will affect the formation of wear profiles of the tools, furthermore, the work result will be affected directly by the cutting path of this relative motions. In this paper, the kinematic principle of face grinding process on lapping machines has been analyzed. By means of the concept of pitch point and pitch circles, the complicated grinding process has been converted into two kinds of rotations with the fixed center distance. Two kinds of path curves, i.e. workpiece against grinding wheel and grinding wheel against workpiece, and their relations are analyzed. The geometrical analyses and the manufacture quality of the workpiece are linked with the aid of the cutting velocity, the range of the rotational angle of the cutting traces and the rate of the change of the rotational angle with time. The optimal path curve and kinematic parameters are achieved, and these results are corresponding to the experimental results.