By means of natural vibration analysis and system dynamics simulation, the coupling dynamic characteristics of multi-stage gear transmission and rocker box are revealed
① The natural vibration characteristics of rocker box and multi-stage gear transmission are calculated respectively. The natural frequency and vibration mode of the rocker box (condensation model) are calculated by programming, which is in good agreement with the calculation results of the finite element software, indicating that the box condensation is correct. The modal of multi-stage gear transmission is calculated, and the natural frequency of torsional vibration mode is extracted.
② Based on the characteristics of natural frequency, vibration mode and modal strain energy, the natural vibration characteristics of multi-stage gear transmission box coupling system are analyzed. The results show that the natural frequency of torsional vibration mode of multi-stage gear transmission decreases to a certain extent after coupling the rocker box.
③ The dynamic deformation of the cutting part under rated working condition is checked by 3D animation, and the instantaneous center distance of gear, meshing tooth direction error, dynamic load of gear and bearing, vibration acceleration of rocker box and other data are obtained. The data verify each other and show that the substructure coupling is correct. It is shown that the deformation of the rocker box is an important reason for the eccentric load of the gear.
④ The coupling dynamic characteristics of the cutting part at different speeds are studied, and the influence of the rocker box flexibility on the system dynamic simulation results is analyzed. The results show that: in the non resonance region, the main effect of the coupling rocker box is to increase the eccentric load of the gear pair, but the effect on the dynamic load of the gear pair is not obvious; in the resonance region, the dynamic meshing force of the multi-stage gear transmission reaches the peak (resonance) speed after the coupling rocker box is reduced to a certain extent.