基于磁流变技术的回转机构制动冲击控制

针对起重机回转机构制动时惯性冲击易导致设备损坏的问题,提出了一种通过电流改变扭转刚度和阻尼系数的磁流变弹性体联轴器,实现对冲击振动频率和幅值的控制.根据起重机回转制动时的特点,建立了含齿侧间隙、齿轮啮合刚度与磁流变非线性刚度和阻尼的系统动力学方程,推导出系统几个关键性参数与电流间的函数关系.运用数学软件对方程进行数值求解,对联轴器扭矩特性、阻尼特性、齿轮啮合力及制动效果进行了分析.结果表明,磁流变联轴器具有很强的扭矩传递能力,在不影响制动效果的情况下可以显著地降低冲击振荡频率,对冲击载荷峰值也有一定的抑制效果.

Control of Braking Impact of Slewing Mechanism Based on Magnetorheological Technology

Abstract： Aimed at the inertial impact of the crane slewing mechanism brake, a kind of magnetorheological elastomers shaft device was proposed to control the vibration frequency and amplitude of impact. Dynamics equations considering the backlash, time varying meshing stiffness and nonlinear stiffness and damping coefficient of magnetorheological elastomers were established based on the working characteristics of the slewing mechanism, and the function relation between the key parameters and the electric current was deduced. The numerical solutions to equations were obtained, and the coupling torque characteristics and damping characteristics as well as the gear meshing force and braking effect were analyzed. The results show that the magnetorheological elastomer based coupling has a strong power transmission capability. It does not affect the braking effect but it can significantly reduce the shock oscillation frequency. In addition, it can inhibit the impact load peaks.