Design And Motion Simulation Of Sheet-Transferring Mechanism Up-Swinging Around Fixed-Centre

The sheet-transferring mechanism has an important effect on the efficiency and quality of sheet offset press and the dynamic analysis of it has actual value for enhancing the performances of the machine. The paper proceeded with the fund project of Beijing Municipal Education Commission- "Research on Sheet-Transferring Mechanism of Octavo Offset Press" . The profile of the driving cam was worked out by motion synthesis of the mechanism in the condition of rigid hypothesis and then the dynamic analysis was performed. The above research provided theoretical reference for the improvement of this type of sheet-transferring mechanism. The specific results were summarized as follows:(1) Four typical motion curves for transferring gripper were designed and the 3-4-5 polynomials curve was chosen as the motion laws of the gripper by contrasting the characteristic values of them. It was analyzed that how the distribution of periodic time influenced on the motion idiosyncrasies of the gripper and the feasibility to simplify the curve was also discussed.(2) Kinematic synthesis proceeded from the gripper by using complex-algebra-vector solution then the motion laws of every part of the linkages were investigated. The cam profile and relative parameters including press angle,radius of curvature were calculated according to the motion of the oscillating roller follower. The cutter path used for machining the cam was also designed.(3) The effects that the inertial loads acting on the linkages and the cam's driving-torque were studied based on the D'Alembett's principle. Through the research the conclusion that the position of the grippers bar on the gripper-rocker has a crucial influence on the inertial loads of the sheet-transferring mechanism was drawn.(4) Given the reasonable supposition the mechanism was simplified to a mathematical model of elastic-body system. The dynamic response of the gripper was worked out by solved the vibration equation. It was proved to be feasible that the mechanism was designed with the rigid hypothesis. Thus the design of the sheet-transferring mechanism was completed.(5) The soft being used for designing and analyzing the sheet-transferring mechanism was developed by using Visual C++ 6.0. It could perform dynamic analysis of the mechanism and could also be used as the general soft for designing and analyzing the plate cam with an oscillating roller follower.