On Dynamic Performance Analysis And Design Of A Double-Knuckle Servo Mechanical Press

Forging machine is one of the most important equipments in manufacturing and also are main equipments in some industries such as information, electricity, machinery, automobile, instrument and so on. Servo driven mechanical press is a kind of controllable mechanism which possesses the merits both of the traditional press with high speed, effective, lost cost and modern parallel mechanism with high precision and controllability. Based on AC servomotors, NC heavy duty mechanical driving is a combination of new and high technology and traditional mechanical technology. This paper combines the urgent need of high-quality forging sheets by state's major industries and present research status of mechanical press, with the support of National High-Tec Research and Development Plan, a comprehensive research on multi-link servo press is developed including parallel servo-motor mechanism design based on architecture topology, dimension optimization base on atlas, performance character which takes account into screw and servo motor constrain and static and dynamic analysis of the press body. The paper has six chapters with following contents:1. discussed the superiority of the mechanical press driven directly by servo motor, analyzed and summarized the characteristics of 2-DOF mechanism; based on the topology optimization theory, designed new type of parallel driven mechanism, the 5R2P parallel mechanism as new servo motor ,with the prototype of seven bar in the hybrid press mechanism; formed math model of the capacity of the two servo motors, and made cyber simulation of this new mechanism.2. Presented the performance indices of the double-knuckle servo press, then based on performance atlases over bounded solution space, built up the relationship between performance indices and link lengths and depicted then performance atlases over the bounded solution space. In performance atlases, optimal dimensional region can be determined to maximize the mechanical advantage of the punching mechanism and minimize payload distribution among the links. Searching from the optimal dimensional region, the dimensional design with global optimization is got for punching mechanism based on the complex method of optimization. Finally, a case study demonstrates the optimized synthesis method for the double-knuckle servo mechanical press.3. Conducted FEA static and dynamic characteristic analysis on the press body by ANASYS, and made some structure modifications based on the stress and deformation analysis of the various parts of the press body, furthermore will provide help for the servo press'mechanism dynamic performance optimization in the future.4. According to the characteristics of the servo press, the dynamic equations of the flexible links and rigid bodies are described in the local coordinates. Then the differential equation of the system is formulated using the kinematic relationships between the links and the rigid bodies.Then interpolated the NURBS curve fitting the mission characteristic processes, to meet the technical parameters of the capability of the servo press, which is suitable for different materials and the same material with different thickness in different frequency of stroke and the different speed of the mission.