目前精密塑料注射成型装备的数字样机广泛采用多刚体动力学系统,没有考虑机构运动过程中构件的内应力大小和分布情况,难以求解大位移的合模运动与小位移的结构变形的相互耦合问题。针对精密塑料注射成型装备复杂的动力学特性,建立双曲肘连杆式合模装置数字样机,并在此基础上柔性化处理拉杆、十字头连杆、前肘杆、销轴等关键零部件,获得拉杆的前22阶模态。在合模装置数字样机的仿真分析中,十字头连杆起动过程出现速度拐点,需要考虑十字头连杆的弹性变形。对双曲肘连杆式合模装置数字样机进行刚柔耦合动力学分析,通过中心差分法,求解合模装置数字样机起动过程中十字头连杆的弹性变形,为精密塑料注射成型装备新产品的开发提供了可借鉴的方法。
The multi-body dynamics is widely used in the current research of the digital prototype of precision plastic injection molding equipment,without considering the stress and its distribution of components in the motion of closing mechanism.Therefore,it is difficult to solve the mutual coupling problem between the large displacement of the mold movement and the small displacement of the structural deformation.For the complex dynamic characteristics of precision plastic injection molding equipment,the digital prototype of double toggle mold closing device is established with flexible parts of tie bars,crosshead rod,front elbow bar and pin,then,before order 22 modes of tie bars can be obtained.In the simulation analysis of digital prototype of mold closing device,there is a velocity turning point of crosshead rod in the starting procedure,which needs to consider the elastic deformation of the crosshead rod.In the rigid-flexible coupling dynamics analysis of double toggle mold closing device,by using the central difference method,the elastic deformation of crosshead rod is resolved in the starting procedure,and a reference method is provided for the development of precision plastic injection molding equipment.