Effects of ranging arm housing’s large deformation on the dynamic responses of the cutting transmission system for a drum shearer

Abstract

The drum driving system is the weakest part of a drum shearer, and most of the previous dynamic analyses neglect the housing flexibility. Therefore, some efforts are needed to refine the dynamic model and sufficiently understand the dynamic behavior of the drum driving system. Establishing a system-level model of the drum driving system is challenging because the drum driving system consists of many components such as the cantilever loaded housing, multistage gear transmission, electric motor, and drum. In this study, an improved three-dimensional gear model with the time-varying pressure angle and contact ratio due to center distance variation is proposed. Then, a standard coupling method is proposed to construct the hybrid dynamic model of the drum driving system automatically. Finally, a comparative analysis of the dynamic responses of the drum driving system under two loading scenarios (i.e. applying only the cutting moment and applying both the cutting moment and cutting force) revealed that the three-directional cutting force was the primary external factor that leads to the housing deformation. And some principles for designing the drum driving system under such a large deformation condition are also identified.