Spiral bevel gear pair for upper transmission box of excavator

The utility model discloses a spiral bevel gear pair for an upper transmission box of an excavator. The gear pair comprises a driving gear and a driven gear which are of a spiral bevel structure, wherein the driving gear and the driven gear are meshed with each other, the end face of the driving gear, which is far away from a gear shaft, is of a concave spherical surface structure, the tooth spiral line of the driving gear rises from the low left corner to the upper right corner in an inclined manner, and the tooth spiral line of the driven gear rises from the lower right corner to upper left corner in an inclined manner, a shaft hole is arranged in the driven gear, and a spline is arranged at the inner side of the shaft hole. According to the utility model, as the end face of the driving gear, which is far away from the gear shaft, is of the concave spherical surface structure, on the condition that the driving gear is stressed equally, the steel raw material adopted in production and manufacture is effectiv