Bevel gear set for spindle horizontal-vertical conversion and box body of bevel gear set

The invention discloses a bevel gear set for spindle horizontal-vertical conversion and a box body of the bevel gear set. The bevel gear set comprises a bevel gear shaft, bevel gears, a spindle, a flange disc and a shell. The bevel gear shaft is driven by a motor and a coupler to rotate, and the bevel gear shaft drives the bevel gear (1) meshed with the bevel gear shaft to rotate; the bevel gear (1) and the bevel gear (2) are fixed through a central shaft, and the two bevel gears are the same in rotating speed; the bevel gear (2) drives the bevel gear (3) meshed with the bevel gear (2) to rotate, and the bevel gear (3) is connected with the spindle through a spline; and the bevel gear (3) drives the spindle to rotate. According to the relative rotating relation of shells of the front portion and the rear portion, the horizontal-vertical conversion of the spindle of a machine tool is achieved, and the machining technology of parts is optimized.