A rice thresher is an agricultural machine designed to separate rice grains from harvested paddy stalks quickly and efficiently. It consists of a feeding tray, threshing drum fitted with spikes or teeth, concave screen, cleaning blower, grain collection unit, and a motor or engine drive system. The machine is built to minimize grain loss and reduce the labor required in traditional manual threshing methods.

In operation, harvested rice stalks are fed into the machine through the feeding tray, where the rotating threshing drum strikes and rubs the stalks against the concave screen to detach the grains. The separated grains then pass through a cleaning system, where a blower removes chaff, dust, and other light impurities. Clean rice grains are collected through the discharge outlet, while straw and waste materials are expelled separately. Rice threshers are widely used by farmers and grain processors to increase productivity, improve grain quality, and reduce harvesting time.