Tends in development of technical means for sunflower heads threshing (review)

Currently, the available means of mechanization for threshing sunflower heads often do not meet the requirements of breeders for injury and do not guarantee a complete cleaning of seed residues. A technically accessible way to achieve this goal is to create the necessary conditions to reduce the strength of attachment of seeds to the receptacle immediately before threshing. Then, when threshing, much less effort will be required to extract the seeds from the head, and, consequently, a lower intensity of the impact of the working bodies on the threshed seeds. In the process of studying the designs of threshing devices and threshing methods, the main factors that have a significant impact on the threshing process were identified. Based on a review by author’s certificates and patents, we established that the main method of threshing seeds is a knock followed by wiping, carried out by means of a multi-roll threshing device having various designs of working bodies. Also we established that mechanical processes in different mechanical devices are formalized by the same physical laws, but the priority and ranking of the dominant processes for each of them are different. Analyzing the review material, author’s certificates and patents, we can conclude that the new thresher must perform the following operations: compression, vibration, wiping, knock.