Underground maintenance-free walking mechanism of thin seam coal mining machine

The utility model discloses an underground maintenance-free walking mechanism of a thin seam coal mining machine. The device comprises a shell, a large end plate, a guide sliding shoe, a spline shaftand a toothed rail wheel, the spline shaft is rotationally mounted on the shell through a first maintenance-free bearing; a bearing seat is arranged on the shell; the guide sliding shoe is sleeved onthe spline shaft; the guide sliding shoe comprises a left lug plate and a right lug plate; the toothed rail wheel is arranged between the left lug plate and the right lug plate, the toothed rail wheelis connected with the spline shaft through a spline, a radial positioning block for protecting the spline is arranged on the toothed rail wheel, the large end plate is rotationally installed on the spline shaft through a second maintenance-free bearing, and the spline shaft is sleeved with a bush for installing the second maintenance-free bearing. According to the utility model, the first maintenance-free bearing and the s