考虑动载荷与动态磨损系数的直齿轮传动系统动态磨损特性

Dynamic surface wear characteristics in spur gear transmission system with dynamic loads and wear coefficients

为揭示齿轮传动系统齿面动态磨损特性,通过Weber–Banaschek公式计算获取啮合齿轮对的时变啮合刚度,基于此建立包含非线性齿侧间隙和内部误差激励的齿轮传动系统运动学方程,计算获得系统轮齿啮合时载荷沿啮合线的动态变化规律。根据齿面粗糙度和当前啮合点最小油膜厚度,建立齿面动态磨损系数的表达式。以轮齿的起始啮合点和最终啮合为区间,将渐开线齿廓进行离散化处理,建立离散化的齿面动态磨损模型并对其进行特定参数下的仿真计算。研究结果表明:由于动载荷、动态磨损系数和滑移速度等参数的影响,主从动齿轮齿面累积磨损量沿渐开线齿廓呈现非均匀分布,节点处最小,齿顶处最大;小齿轮的齿面磨损程度比大齿轮更严重;当传动比和模数变化时,齿面累积磨损量均存在变化趋势明显的敏感区域。

In order to reveal the characteristics of gear surface dynamic wear and the effect of parameters in gear transmission system, the equations of motion with nonlinear backlash, internal error excitation and time-varying mesh stiffness, which was calculated by employing Weber-Banaschek formula, were built to obtain the distribution of dynamic loads along the line of action for involute gear. The minimum oil thickness at current gear teeth contact point and the gear teeth surface roughness were utilized to acquire the expression of dynamic surface wear coefficients. The discretization of involute gear profile was conducted by dividing the current pressure angle increment between the first mesh point and final mesh point equally. The tooth wear equation proposed by Flodin was introduced and the discrete dynamic surface wear model was established to simulate the wear process for an engaging gear pair under certain system parameter settings. The results show that the accumulated surface wears are distributed along the involute gear profile unequally with maximum wear at tip point and minimum wear at pitch point respectively under the influences of dynamic loads, dynamic wear coefficients and relative sliding velocities. The accumulated surface wear of pinion is more serious than that of the gear and this phenomenon is validated by engineering practice. There exist relatively sensitive regions of gear surface accumulated wear while the transmission ratio and gear module are varied.