Design development and evaluation of a low cost paddy thresher

Abstract

Though several high capacity threshers are available in the country for different crops, no thresher is found suitable for small and marginal rice farmers. Hence a low cost portable paddy thresher was developed and tested. The power operated machine consists of base, side frames, front grain shield and wire-loop cylinder. The power from the 0.5 hp motor is transmitted to the cylinder shaft by belt and pully arrangement. The optimum cylinder speed is 400 rpm. The capacity of the thresher at 14.26 per cent moisture content is 451.84 kg paddy per hour and threshing efficiency is 95.08 per cent. The mechanical damage of the grain is negligible. Two labourers are required for the whole operation. The size of the thresher is 635 x 500 x 715 mm having a gross weight of 47 kg. The cost of the thresher was worked out to be around Rs. 3600 and the cost of operation for threshing paddy was Rs. 3.00 per quintal. The unit can be fabricated by local artisans from the readily available materials and can successfully be maintained by small and marginal farmers.