It is composed of a gear box, a spindle box, a circular upright, a worktable, a bracket, a base, an electric box and the like, wherein the gearbox is combined on the spindle box, the spindle box is sleeved on the upper part of circular upright, and is able to be moved up and down, and is located above the machine tool. The worktable is sleeved on the bracket, the bracket is sleeved in the middle of circular upright, and the circular upright is installed on the base.