Corte de base inercial com baixa velocidade de avanço da colhedora.

Abstract

Base cutting of sugarcane is done at soil level using the impact cut principle. High knife velocity combined with low harvester ground speed result in excessive number of cuts per unit displacement. It means higher cane losses and low energy efficiency of the base cutting process. The disc type base cutter has this limitation when knife tangential velocity is kept over 20 ms-1 and ground speed under 500 mh-1. This work proposes a linkage driving a knife with oscillating motion performing impact cut with 1/3 the number of cut per unit motion of the conventional disc cutter. A vector model was developed to simulate knife trajectory. Simulation showed differences between forward and return knife trajectories of 100 mm in horizontal travel direction and 40 mm in the vertical direction. The linkage showed knife cutting velocities varying in the range of 25 to 40 ms-1 together with return velocity of 5 ms-1. The knife tip presented a concave trajectory in the vertical plane which is convenient to reduce knife-soil interaction when soil is not adequately leveled.