The influence of the speed of the floating conveyor to the separating ability of the bottom of the inclined chamber

The results of the laboratory experiment confirming the possibility of preliminary separation of free grain from the combed grain heap before it enters the threshing chamber are presented. In particular, it is proposed to provide a combine harvester with a device for pre-separation of free grain, mounted between the inclined chamber and the threshing device. It includes two drums and an infinite mesh cloth. To intensify the process of separation of the combed grain heap on the fraction of the axis of rotation of the drums are made eccentrically with respect to their geometric axes. All studies were carried out on wheat varieties «Moskovskaya 56». Grain moisture was about 12 %. The speed of movement of the floating conveyor had five levels of variation in the range of 3-5 m/s. Flow oceanog grain heap was about 10 kg/s at a content of 80 % of free grain. The length of the mesh conveyor was 2 m, and its rectangular cells had dimensions of 17×15 mm. Thus, according to the results of scientific research, as the speed of the mesh conveyor increases, the amount of free grain passing through its cells tends to decrease, and the amount of grain coming down from it, on the contrary, to increase. The maximum passage of free grain (94,66 %) corresponds to the minimum speed of the mesh conveyor, equal to 3 m/s. The presence of free grain is due to the fact that during a series of experiments, the length of the separating surface was insufficient. To determine the optimal length of the mesh conveyor, the nature of the process of preliminary separation of free grain from the combed grain heap is considered. Extrapolation of this process shows that the minimum length of the mesh conveyor, providing 99 % of the free grain from the combed grain heap, must be at least 2,69 m. The practical implementation of such a technical solution in the design of a modern combine harvester will increase its productivity when combing plants at the root, reliably eliminating the possibility of crushing free grain by the working bodies of the threshing device.

crushing, free grain, combine harvester, comb, mesh conveyor, pre-separation of the combed grain heap