非对称式N次谐波凸轮型线设计方法的研究

Study of Designing Method for Aymmetrical Nth-Degree Harmonics Cam Profile

提出了一种非对称N次谐波凸轮型线的优化设计方法。新设计方法能有效控制N次谐波凸轮型线的设计结果,实现凸轮型线在360°内二阶导数连续;气门开启速度高于关闭速度;上升缓冲段终点加速度大于下降缓冲段终点加速度;下降段正加速度极值低于上升段;解决了N次谐波凸轮型线设计中存在的缓冲段加速度波动突变的设计难点。

An asymmetrical Nth-degree harmonics cam profile optimization design method was proposed. With this method the designed cam profile can be controlled availably. The following characteristics can be achieved. The two-degree differential coefficient of the designed cam profile is continuous within 360°. Valve＇s open velocity is higher than that of the close up. The acceleration at the climb transition phase＇s end is higher than that at the come down transition phase＇s end. The maximum positive acceleration on climb phase is lower than that on the come down phase. The unreasonable undulation of acceleration on the transition phase was resolved, which has puzzled Nth-degree harmonics cam profile designer for a long time.