Model analysis and verification of 2K-H planetary gear system

Abstract

The planetary gear system is the important part of the cutting unit in a coal shearer, and its performance is directly related to the output efficiency in coal mines. Analyzing the natural frequencies and vibration modes of a planetary gear system in a coal shearer is helpful for designing and monitoring the planetary gear system. So a lateral-torsional coupled free vibration model is proposed with the shaft stiffness of the sun gear based on the analysis of a purely torsional model. The solutions are determined by using the modal superposition method. Taking the planetary gear system in the cutting unit of a YBCS2-400 type coal shearer as an example and studying the natural characteristics, the vibration modes of the undamped system could be classified into three types – rotational mode, translational mode and planet mode. The associated reduced-order eigenvalue for each type of vibration mode is derived and the analytical expression of natural frequency is presented for the planet mode. The established model is validated by comparing it with the results of a finite element model, and the effect on the vibration frequencies of the transmission and width ratio has been obtained by means of the finite element model.