To determine the optimal tilt angle of the lattice holes of the bottom of the inclined chamber

Abstract

According to the results of laboratory experiments, the optimal angle of inclination of the holes of the lattice bottom of the inclined chamber of the combine harvester is established, which provides maximum separation of free grain from the combed grain heap before it enters the grind chamber. This allows you to minimize the intake of free grain to the threshing device, securely eliminating the probability of crushing the working bodies grind. Studies were carried out on wheat varieties «Moscow 56». The grain moisture content was about 12%. The speed of the conveyor 3 m/s and the angle of inclination to the horizon of 45° correspond to similar parameters for most modern combine harvesters. The angle of inclination of the lattice bottom opening had seven levels of variation within 0-90°. The feed of the combed grain heap was about 10 kg/s with a content of 80 % free grain. The length of the removable grating bottom was 0.95 m, and its rectangular holes had a size of 160×8 mm. To eliminate the effect on the output parameter, the area of the «live section» of the holes of the lattice bottom in all series of the experiment was taken the same. Thus, results of scientific researches, increasing of the angle of inclination amounts of free grain passed through the holes of the bottom lattice is reduced, and the number came down from his grain, on the contrary, increases. The maximum separation of free grain 68,7 % corresponds to the angle of inclination of the holes equal to 0°. To ensure complete separation of free grain from the combed grain heap, the length of the separating surface must be at least 1,18 m. This technical solution can be implemented, for example, in the inclined chamber of the grain harvester KZS-1218 «Polissya GS-12», which has a length of about 1,3 m.