节曲线向径以线性速度变化的非圆齿轮研究

Study of noncircular gears with pitch curves variable with linear speed

提出一种根据给定中心距和传动比范围设计封闭非圆齿轮的方法。在其节曲线形成过程中,引入了节曲线向径变化速度,根据封闭非圆齿轮传动的条件,构建的线性函数,得到节曲线向径以线性速度变化的非圆齿轮;推导新式齿轮的凹凸性、弧长、及压力角公式。通过仿真计算,得到了时间参数1不同的3种非圆齿轮节曲线,比较了3种节曲线及相应传动比函数的变化趋势,总结出传动比函数的对称性随1的变化规律,为新型齿轮的设计选用提供了依据。研究表明:节曲线方程由二次多项式构成的新式齿轮,相对其它非圆齿轮计算简单,构造方便。

A method for designing noncircular gears is presented under given center distance and transmission range. A velocity parameter is adopted during constructing pitch curves. A linear function of closed pitch curves is built according to its feature. The pitch curves of noncircular gears with linear speed are derived. The concave-convex property, arc length and pressure angle of the new noncircular gears are deduced. Three pairs ofnoncireular gears are simulated with different time. Comparing the pitch curves with transmission ratio, the varying regularity of the symmetric characteristics of transmission ratio is obtained. It will provide a theoretical foundation for the design and choice of the new kind of gear pairs. The simulation results show that the calculation and design of noncircular gears by quadratic are easier than that of other noncircular gears.