点啮合齿面CNC制造技术的曲面包络逼近法

Envelopment-approach to Manufacturing of Spiral Bevel Gears Based on Computer Numerical Control Cutting Machine

提出一种在Free-Form型五轴联动数控机床上加工具有预定齿面啮合特性的点啮合准双曲面齿轮齿面的新方法——曲面包络逼近法。与以往的齿面加工方法不同,在新的齿面展成方法中,齿面展成运动是在沿预定接触迹线的曲面活动标架下设计的。该方法展成的齿面在指定的接触迹线附近与目标齿面有二阶切触,而在齿面的其他区域,该方法展成的齿面能以最小偏差逼近预定的齿面,这表明新方法能展成具有预定啮合特性的齿面。实例说明了所提出方法的可行性和精确性。

A new method（envelope-approach theory） for generating the meshing characteristic- oriented design of point-contact spiral bevel gears tooth surface was presented by application of the five-axis simultaneous CNC cutting machine. Differing from previous studies, the new method was derived from the idea of motion of moving trihedron along a predesigned path of contact on the predesigned （theoretical） tooth surface. The generated tooth surface provided by the new method has tangency of second order with the predesigned （theoretical） surface along the predesigned path of contact and the predesigned （least）warping in regions that differ from the path of contact. This means the new method can generate meshing characteristic-oriented design tooth surfaces. An example was given to prove that above-mentioned manufacture method is accurate and feasible.