超越弹簧离合器可用于高速直升机传动系统,具有简单、可靠、质轻的特点。离合器依靠弹簧和输入、输出壳体的摩擦来传递扭矩,在正向传递动力过程中要满足的自锁条件下,分析了超越弹簧离合器接触条件下的最小摩擦系数,同时研究了弹簧离合器用材料4Cr5Mo Si V钢的摩擦系数随表面粗糙度的变化规律,结果表明摩擦系数随着表面粗糙度的增加,先减小后增大,Ra存在一最佳值,在此Ra值下,摩擦系数最小;由于在反向超越过程中,磨损是超越离合器一直存在的问题,基于Archard磨损计算模型,利用组合磨损计算方法,得出了超越弹簧离合器的磨损寿命。
In order to effectively improve meshing performance of spiral bevel and hypoid gears generated by the duplex helical method, the effects of straight lined and circular cutting edges profile on meshing and contact of spiral bevel and hypoid gears were investigated analytically. Firstly, a mathematical model of spiral bevel and hypoid gears with circular blade profile was established according to the cutting characteristics of the duplex helical method. Based on a hypoid gear drive, the tooth bearings and the functions of transmission errors of four design cases were analyzed respectively by the use of the tooth contact analysis(TCA), and the contact stresses of the four design cases were analyzed and compared using simulation software. Finally, the curvature radius of the circular profile blade was optimized. The results show that the contact stresses are availably reduced, and the areas of edge contact and severe contact stresses can be avoided by selecting appropriate circular blade profile. In addition, the convex and concave sides are separately modified by the use of different curvature radii of inside and outside blades, which can increase the flexibility of the duplex helical method.
