Ustability improvement of face-milling spiral bevel gears by modified radial motion (MRM) method

In recent years, the development of CNC hypoid generator has made it possible to perform nonlinear correction motions for the cutting of the face-milling spiral bevel and hypoid gears. The existing lengthwise curvature modifications are primarily achieved by changing the cutter diameter or the cutter blade pressure angle with tilt cutter axis. However, both lengthwise curvature modifications need to rebuild the head cutter. In this paper, a methodology is proposed to improve the adjustability of the spiral bevel gear assembly by modifying the radial motion of the head cutter in the machine plane of the hypoid generator. The head cutter is unchanged in the proposed method. Therefore, the adjustability for gear assembly can be on-line controlled by a CNC controller without dismounting and rebuilding the head cutter. The numerical results show that the bearing contact ratio is virtually the same as initial design while the adjustability is increased dramatically. (C) 2004 Elsevier Ltd. All rights reserved.