Influence of the shape of potato tubers on the quality of separation into fractions by the working bodies of potato sorting machines

Abstract

Many agricultural producers are faced with problems of sorting flat and oval potato tubers into size fractions using roller sorting surfaces. The paper studies the influence of the shape of potato tubers on the speed of their orientation relative to the calibrating holes, and, as a consequence, the performance indicators of machines and the quality of the process performed. The aim of the study is to determine the causes of damage to tubers during sorting and ways to eliminate them. There was substantiated the relationship between the kinematic parameters of the roller surfaces of potato sorting machines and the shape of tubers, which makes it possible to reduce damage and improve the quality of sorting potatoes into fractions. A number of experiments were carried out to determine the relationship between the shape of tubers and the kinematic parameters of the roller surface. In the first experiment, the number of tubers that will pass through the calibrating slot in a certain time was determined at different gear ratios in the drive of the rollers of the calibrating surface. In the second experiment, the time was found for a certain number of tubers of various shapes to pass through the calibrating surface. The graphs of the experimental dependences of the number of tubers of 43 mm thick passed into the calibrating gap between the rollers of 42 mm in 5 seconds on the ratio of the peripheral speeds between the rollers are presented. And the graphs of the dependence of the change in the time of passage of a group of tubers with a thickness of 40 and 42 mm through the gap between the rollers with a width 42 mm from the ratio of the peripheral speeds between the rollers are given. Based on the carried out studies, it was found that the ratio of the peripheral speeds of adjacent rollers, forming the calibrating slot, have a significant effect on the quality of the separation of tubers into fractions and are the cause of damage influenced by deformation. The presented analysis makes it possible to assess the influence of the shape of the tuber on the quality of the separation of tubers by roller calibrating surfaces of potato sorting machines, and also indicates the ways of improving the design of equipment for the finalization of potatoes after harvest and before sale.