Research Of Buffer Device In Oscillating-bar Forging Manipulator

Forging manipulator is one of the important auxiliary equipments for manufacturing large forgings,which is currently the largest special robot on earth that integrates “machine,electricity and liquid”.With the increasing demand of large forgings at home and abroad,many countries have paid high attention to forging manipulator research.Both of forging manipulator's starting condition and braking condition impact on hanging system when it walks among carts.Especially under the braking condition,the manipulator's walking mechanism needs fast movement within a short period of time.Thus,the hanging system will be subjected to a larger inertia concussion.Reasonable buffer device can reduce the vibration and shock of hanging system effectively that plays an significant role on improvement of manipulator's stability and accuracy about its movement.This paper analyzes the buffer device's influence on vibration of the hanging system,aiming at 50 KN oscillating bar forging manipulator under braking condition.By analyzing the force of the cart about the manipulator's starting and braking conditions and calculating relevant datas,which makes it clear that the manipulator cannot meet the demand of its running precision while parking brake at top speed.The paper puts forward the method of graded decelerating to guarantee the running precision of cart,giving an optimal braking speed to the forging manipulator and determining the initial velocity of the vibration for the hanging system.Based on the study of the braking condition about forging manipulator,there are two kinds schemes of buffer device are established.By equating stiffness and damping to buffer device simplified mechanics model of hanging system.The paper analyzes the kinetic and potential energy of the system on account of Lagrange method,establishing the systemic dynamic equations.In the MATLAB environment,using the four order Runge Kutta method to work out equations.The influence of stiffness and damping on the vibration of the system is analyzed,which provides the basis for determining the parameters on the buffer stiffness and damping of oscillating bar manipulator.Meanwhile,the paper obtained the change rule about clamping bar's centroid and the hanging bar's swing angle under braking condition.With the comparison and analysis of two schemes,the optimal scheme is considered synthetically from the swing range and the vibration time of the hanging bar which provides a reference to the layout of the buffer device with 50 KN oscillating bar manipulator.After using dynamic simulation software ADAMS,the paper obtained curve of the influence on the buffer device about the system vibration under braking condition in the hanging system of the manipulator,verifying the correctness and rationality of the theory.By studying the buffer device of 50 KN oscillating bar forging manipulator in this paper,it provides a theoretical basis for the design of the buffer device,and provides a reference forthe layout scheme of the buffer device.