應用於橢圓車削之新型快速刀具滑台設計與控制

The main purpose of this thesis was to develop an innovative fast tool stage for the ellipse turning based on the CNC lathe machining a shaft with variable ovalities. The mathematical model of the fast tool stage was first developed, then the corresponding kinematics were analyzed, including the crank rotation angle, the rocker swing angle, the tool feeding displacement, and the velocity, acceleration and jerk. The particle swarm optimization algorithm was employed to synthesize the linkage dimension of the fast tool stage considering the tool feeding jerk being the minimization. Finally, a laboratory built lathe with the fast tool stage combined with an electronic cam was used to implement the ellipse turning. Moreover, the inverse kinematics was solved to plan the trajectory of the tool feeding displacement so that the caused machining errors were compensated. The elliptical machining accuracy for the fast tool stage was further discussed and analyzed through both the elliptical turning simulation and the actual elliptical turning on workpiece. The results show that the elliptical contour accuracy obtained with small elliptic ratio is better than that of the larger elliptic ratio. It implies that the elliptical turning error is mainly related to the maximum cutting depth of the tool, not the spindle speed. The more the feeding amount, the larger the elliptical contour error. It is seen that our developed fast tool stage in this paper is feasible on elliptical turning.