SPEED AND ROTATION VARIATIONS IN GATHERING COFFEE MACHINE

The mechanized harvesting operation of coffee sweep from ground have a great importance, due the value of the coffee that was lost by the harvest process, as well as the breakdown of the cycle of pests that can damage the coffee. To change work settings can influence significantly the capacity of the gathering system. Due, the objective of this study was to evaluate the influence the speed of displacement and rotations of the components of gathering coffee machine in its performance. The experiment was carried out in the municipality of Presidente Olegario-MG on coffee plantations aged 10 to 11 years. The field, presenting an average of 990 kg ha(-1) of coffee present in the soil after the machine harvest. The engine rotations of the tractor evaluated were 146.6, 162.3, 178.0, 193.7, and 209.4 rad.s(-1) combined with the 1st A and 2nd A gears, resulting in different working speeds. The treatments were distributed in randomized blocks with five replicates. The variables analyzed were the gathering efficiency, cleaning efficiency, coffee losses, and percentage of mineral and vegetal impurities. It was concluded that the gathering efficiency was higher when working with 178.0 rad.s(-1) at 1.26 km h(-1), resulting in lower coffee losses in the operation, a preponderant factor in the study. On the other hand, the best cleaning efficiency of the machine was found when using 193.7 rad.s(-1) and 1.37 km h(-1).