Tool Wear Improvement and Cutting Force Prediction in Face-hobbing of Bevel Gears: Workpiece In-process Model, Instantaneous Un-deformed Chip Geometry and Cutting Force Prediction in Face-hobbing of Bevel Gears as well as Tool Wear Improvement by a New Blade Design

摘要

Due to complexities of face-hobbing of bevel gears, such as the intricate geometry of the cutting system, multi-axis machine tool kinematic chains and the variant cutting velocity along the cutting edge, deriving the instantaneous un-deformed chip geometry and predicting cutting forces, as the most important characteristics of material removal, are challenging. In the present research, all these complexities have been taken into consideration to obtain the un-deformed chip geometry and predict cutting forces. The in-process model of the workpiece is derived using workpiece discretization into disks and intersecting the blades with them. In addition, in this paper, a new method to design cutting blades is proposed by changing the geometry of the rake and relief surfaces to avoid those large variations while the cutting edge is kept unchanged. In the proposed method, the working rake and relief angles are kept constant along the cutting edge by considering the varying cutting velocity and the machine tool kinematics. By applying the proposed method to design the blades, the tool wear characteristics are improved especially at the corner.