Innovation of rocker box and multistage gear transmission of shearer cutting part

① Aiming at the problems of modeling difficulty and low computational efficiency of multi-stage gear system dynamics, an efficient general modeling method is proposed. In this method, a unified writing form of linear or nonlinear dynamic models of each component in the gear system is designed, which makes the modeling method universal; then, according to the rigid, linear elastic or nonlinear connection mode between components, the corresponding coupling matrix is derived, and a large number of component dynamic models are automatically coupled through matrix operation, so that the dynamic models of various multi-stage gear systems can be quickly established Dynamic model.

② A three-dimensional gear dynamic model is proposed, which can be used for supporting system and large deformation of gear teeth. In this model, the slice meshing excitation algorithm is improved. For the first time, the meshing angle and actual meshing interval of each slice gear pair are expressed as time variables related to the deformation of the system (but the existing researches are all constant). The meshing excitation under three-dimensional large deformation of the system is more truly simulated, and the dynamic simulation accuracy of the heavy load flexible support gear is improved. At the same time, the model integrates the rigid rotation of the gear, which is suitable for the simulation of the speed change process and is easy to couple with other substructures of the system.

③ A new method of three-dimensional topological modification for multi-stage gears is proposed. In this method, the actual meshing state of the gear during operation is obtained by dynamic simulation, which is used as the input condition of gear modification, and the fine contact algorithm is used to carry out the tooth direction modification considering the stress concentration at the edge of the gear; the analytical formula of meshing force considering the three-dimensional deformation of the support system and the tooth direction modification is derived, which takes into account the calculation accuracy and efficiency of the tooth profile modification Parameter design and system dynamics simulation are carried out alternately and repeatedly to improve the overall accuracy of multi-stage gear 3D topology modification.