Sand mixing device for casting machining

A mixing barrel is formed by combining two barrel bodies of semicircular structures, the two ends of the mixing barrel are connected with a first supporting frame and a second supporting frame respectively, a feeding port is formed in one end of the mixing barrel, a discharging port is formed in the other end of the mixing barrel, and an observation window is formed in the mixing barrel. The two ends of the driven shaft penetrate through the first supporting frame and the second supporting frame respectively, one end of the driven shaft is rotationally connected with the second supporting frame, and the other end of the driven shaft extends out of the first supporting frame and is connected with the driven wheel; the driving motor is arranged on the base, the output end of the driving motor is connected with the driving wheel, and the driving wheel is connected with the driven wheel through the driving belt; and the crushing part is arranged on the driven shaft. Through the arrangementof the observation windo