Design and construction of a winnowing machine equipped with a floating bed

In combine machine, at the same time as harvesting, winnowing operation and cleaning of harvested seeds are performed. Some oilseeds (such as sesame, etc.) that can't be harvested by machine (or combine) for now, and areas where for whatever reason the product is harvested with sickle or reaper, Plants are collected in a place (stack) and after the seed arrives or the capsule opens, it is attempted to thresh the cob or shake the cluster (in plants such as sesame). If there is no flattened coating on the ground and under the grain collection site (threshing), along with the seeds, some clods, soils and covers are collected, which in the next stages (processing and consumption in the food industry) should be related to cleaning and separation of clods, soil, covers, etc. from the seed and then the washing of the stored seeds.The basis of the common winnowing machines for separating and cleaning grains from external materials and dust is based on their passage (materials) from several series of riddles and sieve with different meshes as well as wind flow, because from the beginning the waste materials with the main grain are mixed with each other while passing through the sieves and are in direct contact, at the end of the work, the dust remains in the winnowed grains.In this project, the purpose of construction of winnowing machine by changing the cross section in the middle part of the chamber (Venturi tube) equipped with fluid substrate that using wind current is separation of hunks, soil, straw and other plant remnants from the harvested crop during a stage of passing through the machine.Due to the suspension of materials and seeds in the path of passing through the fluid bed, the contact between grain and waste is less and the cleaning of the seeds is done with better quality and quantity.Also, due to the low working stages in this machine compared to conventional winnowing machines, while reducing energy consumption and time (in equal volume), since the cleaning of grains is done with better quality, therefore, less water will be needed in the washing stage and therefore less time and energy is needed in the drying stage of the seeds.

کلیدواژه ها:

“Fluid substrate ، grain cleaning ، threshing ، winnowing machine ، agricultural mechanization