Substantiation of constructive and technological parameters of a cylindrical cleaner of soil impurities of onion harvester

A special feature of harvesting onion is that the composition of the impurities of the onion-soil heap coming from digging up to the separating working organs is soil lumps commensurate in size with onion bulbs, which are difficult to separate into slit (bar elevators, screens) working organs. Secondary separation of onion on the most common secondary separation devices - pinholes - is restrained by the heterogeneity of the mechanical properties of the harvested onions. In well-ripened onions with dead tops the roll-off angles are clearly separated from the rolling-off angles of plant and small soil impurities, but when the undersized tops are separated, it is difficult to separate bulbs and impurities from the paltry hill. The separation of root crops and onions from impurities in mechanical separators is based on the physico-mechanical properties of the interacting products: friction coefficients, surface shape factors, speed recovery coefficients, mass, density and strength characteristics. This circumstance is caused by the fact that the excretion of soil lumps on the slit working bodies (rod conveyors and screens) occurs according to dimensional features and this does not lead to the solution of the existing problem: the separation of soil lumps commensurate in size with onion bulbs. The article presents the design of a cylindrical soil purifier that ensures the maximum completeness of separation of a heap of onions from soil impurities, including from commensurate soil lumps. The results of theoretical studies of a cylindrical soil purifier on the substantiation of structural and process parameters during the separation of onion-seed heap from soil impurities are presented.