Most of the gear couplings are used on machines such as metallurgy, mining, chemicals, and lifting. It is often used in heavy duty applications where there is high efficiency and large adjustment errors between the two axes. The drum-type gear coupling can compensate the angle generated by the non-coincidence between the two axes, the axial and radial installation errors, and allow the two shafts to have a certain displacement phenomenon. The direction of rotation of the gear coupling is also not uniform, and it can be operated regardless of the direction.