凹形圆锥渐开线齿轮的滚齿法

凹形圆锥渐开线齿轮 (ConcaveConicalInvoluteGear)是一种新型的圆锥渐开线齿轮 (ConicalInvoluteGear) 1～ 3 ] 。圆锥渐开线齿轮的齿面间呈点接触4] ,所以齿面强度比低 ,而凹形圆锥渐开线齿轮的齿面呈凹状 ,齿面间呈椭圆状面接触3 ] ,克服了圆锥渐开线齿轮齿面强度低的弱点 ,同时又具备圆锥渐开线齿轮的全部优点。这种新型齿轮不仅能实现平面齿轮机构的功能5] ,也能实现空间齿轮机构的功能6] ,具有替代传统的非渐开线型空间齿轮机构的可能性 ,所以是一种极具发展前景的机械传动零件。目前加工凹形圆锥渐开线齿轮均采用先滚齿成圆锥渐开线齿轮然后再逐一把齿面磨齿成凹形的加工方法7] ,这种两步加工方法 ,比传统的手工修型加工方法 ,已是极大的进步 ,可是凹形圆锥渐开线齿轮的加工依然存在成本高 ,周期长 ,精度低等问题。为此有必要确立凹形圆锥渐开线齿轮的高精度的一步加工方法。本研究首先从理论上确立了凹形圆锥渐开线齿轮的滚齿加工法 ,然后利用上述理论 ,实际加工了一组凹形圆锥渐开线齿轮 ,以证明了凹形圆锥渐开线齿轮的滚齿加工法的可行性及正确性

Process of Machining Concave Conical Involute Gear

Concave conical involute gear transmission is a new type of conical involute gear transmission, which possesses all advantages of the latter, and overcomes its shortcoming: the lower contact strength, because the former is of ellipsoid contact rather than point contact when teeth engaged. This new type of gear transmission is able to realize not only plane gear drive, but also space one. As a result, being a mechanical transmission with bright future, it is apt to supersede traditional uninvolute space gear mechanism. In spite of that, the process of machining concave conical involute gear is two steps method up to the present, that is hobbing blank into involute bevel gear firstly, and then grinding the tooth flanks into concave ones respectively. It is a great improvement compared with profile modification by hand, but it has the shortcoming of high cost, long machining period and low precision. So it is necessary to develop a new process: one step method, to imprpve the precision. This paper introduces the study in which a new process is established in terms of theory to hob concave conical involute gear firstly, and then according to this process, a pair of concave conical involute gears which mating each other are hobbed to prove its correctness and feasibility.