基于有限位置法的冲压机构摆动力完全平衡设计

Design and Analysis of Complete Shaking Force Balance of Stamping Mechanism Based on Finite Position Method

基于有限位置法对一种具有两个末端执行器的零耦合度平面高速冲压机构进行摆动力完全平衡设计。通过拓扑分析将该机构划分成3个子运动链(SKC),根据树系统划分原则分别确定了各子运动链中连枝构件以及树枝构件的个数;对机构进行位置分析,依次求解各子运动链的质量矩,得到机构总质量矩与各个构件角位置之间的关系;通过求取机构在5个不同位置上的总质量矩建立线性方程,求解得到机构摆动力完全平衡时各树枝构件的平衡配重参数mi^(*)和pi^(*);分析了配重参数mi^(*)、pi^(*)对平衡后总质心轨迹波动及总惯性力的影响。结果表明,改变配重质量参数mi^(*)对最终平衡效果影响较大,取mi^(*)为0.002 kg时,机构总质心轨迹波动和总惯性力在x、y轴方向上分量比平衡前分别下降了44.44%、59.78%和72.94%、5.40%,验证了摆动力完全平衡条件的有效性。

Based on the finite position method,a zero coupling planar high-speed stamping mechanism with two end effectors was designed and analyzed for complete shaking force balance.Firstly,the mechanism was divided into three sub-kinematic chains (SKC) by topological analysis,and the number of connecting branches and branches in each sub-kinematic chain was determined according to the principle of tree system division.Then,the position of the mechanism was analyzed.The mass moment of each sub chain was solved in turn,and the relationship between the total mass moment and the angular position of each component was obtained.By calculating the total mass moment of the mechanism at five different positions,multiple linear equations were established,and the balance weight parameters mi^(*)and pi^(*)of each branch member were obtained.Finally,the influence trend of mi^(*)and pi^(*)on the total center of mass track fluctuation and the total inertial force after balancing was analyzed.It was found that the change of mi^(*)had a greater impact on the final balance effect.When mi^(*)was 0.002 kg,compared with that before balancing,the components of the total mass center trajectory fluctuation and the total inertial force in the x and y directions were decreased by 44.44%,59.78%,72.94%and 5.40%,respectively,which verified the validity of the condition of complete balance of the pendulum force.The finite position method was simple,effective and easy to program by computer.The research result provided an idea for solving the condition of complete balance of mechanism shaking force.