Substantiation of the parameters of a small-sized thresher for threshing corn cobs

Abstract

One of the leading places among grain and fodder crops is maize. About 3,500 types of products are produced from it. This crop is of great importance as a high-energy food for all species of animals and birds. In the process of corn grain production, the most labor-intensive is harvesting - 60 ... 80% of the total labor costs. In the latter, the most labor-intensive stage of corn harvesting is the threshing of the cobs, the quality of which is characterized by two main indicators - injury to the grain and under-threshing of the cobs. At the moment, a large number of threshers have been developed, different in principles and threshing technological schemes. The existing threshers have a large capacity and are designed to thresh large volumes of corn cobs. However, in the structure of maize cultivation, a significant place is occupied by small crops in the private sector. After the corn cobs are harvested, they are threshed by hand or a variety of hand and mechanical threshers are made. In addition, at the present time, when the physical nature of the process of threshing corn with threshers has not yet been sufficiently studied and their theory has not been sufficiently developed, the distribution of threshers according to the principle of threshing by blow or grinding is not complete. In this regard, the article substantiates a constructive and technological scheme of a small-sized thresher, which provides threshing of corn cobs in a wrapper with minimal injury to the grains. As a result of theoretical studies, rational values ​​of the design and technological parameters of the developed threshing device have been established: moisture content of the cobs 12 ... 22%; threshing drum rotation frequency 300 ... 400 min-1; the height of the teeth is 12 ... 18 mm; tooth pitch 3 ... 8 mm ..