Design and Development of Manually Pedal-Operated Grain Thresher Machine

Thresher machine is one of the agricultural machines that are used to separate the harvested grain
from its stalk by hitting the stalk with rotary drum that have blade on it. The machine has a
number of different components such as vertical stand frame (bars), horizontal bars, and gear
driving pinion gear inside the gear box that is used to drive the whole system to operate, attached
to pulleys, shafts, drum and spring. These components are faced to different type of loads and
forces like shear force, compressive and tensile loads. The dimensions of and materials of the
vertical and horizontal frames or bars were determining by assumption of an operator medium
height. And the dimensions of the main parts like rack gear and spur gear and also the spring is
determined by analyzing it to maximum bending, deflection and shear stress and loads produced
on each of them. The pinion driving gear’s material and profile had been determined by
designing due to the generated torque from the operator applied force.
The material for most of the components of this machine except for the pulleys, shafts and gears
was supposed to be an iron for its availability.