针对曲轴连杆机械式滚切剪机构复杂、设备质量大、造价高等问题,研制出液压缸驱动PR-8R-PRⅡ级杆组的复合连杆剪切机构.通过建立复合连杆机构的位置环方程、力矩平衡方程,求解出构件的轨迹曲线及液压缸的位移、双腔平衡力参数及液压控制系统的传递函数.理论与实测结果表明:液压伺服控制系统模型满足了连杆机构复演滚动轨迹的特性要求;该机构构型设计及机构学综合分析数据正确可行,液压伺服控制系统具有较强的鲁棒性和自适应能力,可在复杂恶劣工况下实现较高的位置控制精度,采用非对称阀控制非对称缸的方法能有效解决剪切机构驱动液压缸的换向冲击问题.
Because of the present problems such as complex mechanical roiling shear mechanism with crankshaft connecting rod, heavy weight of device and high cost, a composite rod shear with the PR-8R- PR I1-level groups driven by hydraulic cylinder was designed. Through the establishment of composite linkage position loop equation, moment balance equation, hydraulic control system model, the locus curve of component and the displacement of hydraulic driver element, the parameters of dual-chamber balance force and the transfer function of hydraulic control system, were calculated. Theoretical and experimental results show that the hydraulic servo control system model can meet the feature requirements of recapitulation rolling track of linkage, and the structure design of such mechanism and its comprehensive analytical data are feasible. Meanwhile, the hydraulic servo control system has strong robustness and self-adaptability, which can achieve higher compensation precision under complex and harsh conditions, and the method of asymmetrically-controlled valve to control asymmetrically-controlled cylinder can effectively solve the reversing impact of the shear mechanism to drive hydraulic cylinder.