等-变速齿轮传动的啮合理论及其主动设计方法研究

Research on Meshing Principle and Active Design Method of Uniform-variable Gear Drive

在变速输纸机构和纺织机械中,要求主动齿轮转动1周时,从动齿轮能够输出多种运动形式。将从动齿轮转动过程中含有周期性的等速和变速运动的齿轮定义为等-变速齿轮,研究了其主动设计方法。根据曲线的光滑特性和节曲线封闭条件,推导了等-变速齿轮的节曲线方程;通过具体实例,建立了I型和II型等-变速齿轮的节曲线,利用Croe软件,给出了其装配模型;利用Adams软件,进行了运动仿真,仿真结果与预先给定的曲线形状基本一致。研究结果表明,通过改变从动齿轮的角速度和角加速度曲线,可以对等-变速齿轮的节曲线进行直接、有效的控制。

In paper-transferring mechanism with variable speeds and textile machines,the driven gear are required to output multifarious motions when the driving gear rotates for 1 cycle.A new gear drive,called uniform-variable gear is proposed.The notion of the uniform-variable gear refers to non-circular gears where the driven gear can bring about uniform,accelerated and decelerated motion during rotation,whilst the driving gear itself rotates at a constant speed.The active design method of this new gear drive is researched.According to the characteristics of smooth curve and closed pitch curve,the mathematical models of pitch curves are derived based on given motion feature of the driven gear.The pitch curves of I-type and II-type uniform-variable gears are built through the design of example drives.The assembly models of uniform-variable gears are given by using the software of Croe.By using the software of Adams,the motion simulation of the gear is carried out,the simulation results are basically consistent with the given curve shape.The results show that,by changing the angular velocity and angular acceleration curves of the driven gear,the pitch curves of the uniform-variable gear can be directly and effectively controlled.