Given that the diameter of the drum is 350mm and the speed of the conveyor belt is 1.2m/s (that is, the linear speed of the drum is 1.2m/s), according to the linear speed calculation formula: linear speed v (m/s) = rotational speed n(r/min)÷60×2π× drum radius d(m). . . Then it is to determine the transmission ratio and number of teeth of the gears inside the reducer. Many estimates can be obtained by looking up the table. I think so too. . Hehe, I forgot. The landlord can borrow a copy of Mechanical Basis from the library and look at belt drive and gear drive, which will be very helpful. Wish you success!