Positioning device for machining internal spline of integral differential mechanism

The utility model belongs to the technical field of integral differential mechanisms, and particularly relates to a positioning device for machining an internal spline of an integral differential mechanism. Comprising a cylindrical mounting base, a cylindrical middle mold base and a positioning reference base which are fixedly connected in sequence from bottom to top; a limiting seat mounting hole is formed in the axial direction of the mounting base, a limiting seat is arranged in a matched mode, the positioning reference seat comprises a connecting column and a positioning block, one side face of the pressing block is fixedly connected with the lateral plane of the positioning block, an upper mounting hole and a lower mounting hole are formed in the middle of the pressing block, and the middle mounting hole and the upper mounting hole form a positioning mounting hole. The integral differential mechanism is vertically inserted into the positioning mounting hole, the lower cylinder of the mounting base is sle